AMAG customer and market information - Austria Metall AG

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AMAG customer and market information - Austria Metall AG

AluReport 1/2010

AMAG customer and market information

Big enough to dare,

small enough to care.

Company

Review and preview 04

Investments

EMC technology 08

Research

Sheet for the aerospace industry 12


02

Contents 01/2010

Editorial 02

Success at the EUROGUSS 03

Review and preview 04

Interview:

process chain optimization 06

Investment in EMC technology 08

First class die casting 10

Research for the

aerospace industry 12

Top ranking with bright products 14

Company and locations 16

Imprint: AMAG Austria Metall AG,

P.O. Box 3, 5282 Ranshofen, Austria,

Tel.: 0043 7722 801-0, Fax: 0043 7722

809-501, holding@amag.at, www.amag.at

Design: Rauscher & Partner, Salzburg

Editorial

Dear Reader,

We were delighted that the AMAG casting

exhibit at the EUROGUSS 2010 aroused

great interest and are already preparing

for an equally first class exchange of information

and ideas with our customers

and partners at the ALUMINIUM 2010 in

Essen.

Despite the difficult economic situation, we

regard the future with optimism because

due precisely to its premium positioning

and diverse specializations, our company

remains on the pace. A highly satisfactory

result was achieved for 2009 as a consequence

of the measures already initiated

at the end of 2008 as a reaction to the crisis,

and this provides us with a launch pad

for the economic recovery of which there

are growing signs.

As a result of the positive response to the

technologically informative and demanding

orientation of the AluReport, this edition

also contains articles about product developments,

which can be translated into

clear advantages for our customers. An

interview with my colleague on the Board,

Helmut Kaufmann, also demonstrates the

importance to a premium supplier of an

optimized, economic and ecological interplay

between all resources along the inte-

grated process chain (smelter, cast house,

rolling mill).

Particularly in periods of economic downturn,

technological progress creates a

springboard for future success. Accordingly,

the smooth start-up of the new electromagnetic,

rolling ingot caster (EMC for

short) constitutes another major step in the

in-house supply of the rolling mill with top

quality materials.

The “AMAG TopCast Alloy Designer”,

which made its public debut at the EURO-

GUSS 2010, also represents a significant

milestone in cast house customer consulting

with regard to optimum alloy selection

in accordance with the mechanical characteristics

of the finished cast part and specific

casting technology parameters.

Safety is a vital issue in the aerospace

industry and provides the impetus for the

further development of the aluminium materials

employed. Major improvements in

fracture toughness, cracking behaviour

and corrosion resistance are attainable

through the targeted influencing of grain

size. Moreover, the know-how thus gained

can also be used in the high-quality sports

article field.

The closing article concerning bright products

also underlines our technological leadership

and explains with numerous application

examples just how technical innovation

can flow into intelligent end products.

Indeed, it is by means such as those mentioned

above, that in 2010 AMAG will continue

to systematically pursue its chosen

path as a premium supplier to top quality

product markets.

Gerhard Falch

Chairman of the Board


AMAG at the fairs in 2010

EUROGUSS 2010, Nuremberg

The AMAG casting stand before the visitor rush

For the second time, the EUROGUSS

provided AMAG casting GmbH with an

excellent opportunity to demonstrate

its capabilities and latest developments

in the cast alloy sector.

A positive response

The numerous visitors to the company

stand and the in-depth nature of the many

discussions concerning current topics and

future developments are both indicative of

the positive response of the market to the

AMAG casting portfolio. The main focus

of attention was the “AMAG TopCast Alloy

Designer”, a software that offers the

possibility of jointly determining ideal alloy

compositions with customers on the basis

of given mechanical and cast house technology

parameters within a given material

standard. The groundwork for the “Designer”

was formed by a scientific study

in which the performance potential of the

226 recycling cast alloy (EN 46200) derived

from variations in alloy composition

was subjected to intensive investigation.

Capable development partners

and suppliers

At the Ranshofen location, AMAG casting

processes approximately 200,000 t of aluminium

scrap annually and thus numbers

among Europe’s largest scrap users. As

ALUMINIUM 2010, Essen

From September 14 – 16, 2010,

Essen will provide the venue for the

eighth ALUMINIUM trade fair.

The ALUMINIUM is the world’s largest

trade fair with the material aluminium as its

theme. Some 900 exhibitors from over 40

countries will be presenting their products,

technologies and services and the 2010

exhibition area is to be expanded to over

60,000 sq m. In order to accommodate

Company

opposed to its competitors in the cast alloys

market, AMAG uses a high percentage

of recycled scrap in wrought alloys,

in the form of rolling ingots as a material

for its own rolled products. Moreover, as a

result of the comprehensive interplay between

the smelter in Canada and the cast

house and rolling mill in Ranshofen, AMAG

has product quality entirely under its control,

whereby innumerable advantages for

the customers of both AMAG companies

result.

AMAG rolling manufactures rolled products

using all the alloy families from 1xxx

to 8xxx and as the most important material

supplier, AMAG casting has the technical

systems, materials and process know-how

needed for the complete mastery of this

material diversity.

The AMAG TopCast Alloy Designer makes its

public debut

this growth and make the design of the fair

clearer for visitors, the halls have already

been divided into thematic segments.

AMAG will be located in Hall 7, which

deals with “semis”. We look forward to

your visit to our stand, where once

again Austrian delicacies will be on

hand to pamper you.

www.aluminium-messe.com

03

AluReport


04

Company

Facing the future with optimism

In 2009, market development was

characterized by a sharp drop in

production and sales in North America

and Western Europe, while China

and India in particular represented

synonyms for growth. AMAG is well

equipped to deal with these difficult

conditions.

The global market in 2009

Fall of 8 % in primary aluminium

consumption

In 2009, global demand for aluminium

fell from the 2008 level of 37.4 million

tonnes to 34.3 million tonnes, which

constituted a decline of 8 per cent.

In particular, consumption dropped by

around a third in the USA and Europe

and by roughly a quarter in Japan and

the CIS.

With 11, 10 and 7 per cent respectively,

China, South Korea and India were the

only countries to demonstrate significant

growth. The sharp dip in aluminium prices

in the final quarter of 2008 already

led to producers shutting down capacity

subject to high production costs. In geographic

terms, the resulting production

cuts were heterogeneously distributed.

The USA demonstrated the biggest fall

in production with a drop of 35 per cent

as compared to 2008. In Western Europe

production shrank by around 20 per

cent and in Russia by some 10 per cent.

Output is China remained stable throughout

the year, while the Middle East saw a

slight increase and India a sizeable rise of

16 per cent over 2008.

Cast alloy production slumps by 35 %

The collapse in the demand for cast products,

which already commenced at the

end of 2008, resulted in a reduction in

cast alloy production of 35 per cent during

2009. However, in the second half of the

year a slight recovery and signs of a turnaround

became tangible. Use of capacity

at the individual remelting plants varied

considerably and partially resulted in plant

closures. Another consequence of low

production levels was massive pressure

on prices and margins, which fell back to

the level of 1997. This was in spite of the

fact that the automotive industry scrapping

premium introduced in numerous

countries secured cast product suppliers

with basic use of capacity.

9.7 % drop in rolled product

consumption

The chilly economic climate, which prevailed

throughout 2009, exerted continuing

pressure on the demand for aluminium

products. According to the respected

Commodity Research Unit (CRU), as

compared to 2008, global demand fell

by 9.7 per cent to 15.6 million tonnes.

North America and Western Europe were

especially hard hit and even the Asia/Pacific

region, which had preciously been a

growth driver, was subject to a slight dip.

The exception was China with expansion

of 7.7 per cent.


AMAG’s 2009 financial year

In spite of the aforementioned effects,

from AMAG’s point of view a stabilization

of the situation in the third quarter led to

an initial recovery in the fourth. Above all,

the provisonal result for the year emanated

from customer trust and, in view

of the general conditions, the resultant

highly satisfactory order intake trend.

The measures introduced immediately

after the outbreak of the crisis in 2008

and the savings and efficiency improvement

programme implemented in 2009

compensated for the negative influences

emanating from the market trend. The introduction

of short time working in March

2009, which continued until the end of

the year, allowed the flexible adjustment

of working hours to the current use of

capacity in individual areas. At the same

time, corresponding savings were made

with regard to overheads.

In the course of the ongoing investment

programme, the electromagnetic rolling

ingot caster (see report in this edition) and

an artificial ageing furnace for long plates

were both successfully put into operation.

Worthy of special note in the material

in 1000 t

25000

20000

15000

10000

5000

0

Increasing demand for rolled aluminium products

17241

Source: CRU Feb 2010

15576

+ 34 %

development area is the initial industrial

scale production of superplastic aluminium-magnesium

sheets and the market

launch of AMAG TopForm ® SPF. In addition,

with the multilayer, high-strength

brazing material AMAG MultiClad ® 7020,

a new sheet semi for innovative applications

in heat exchangers was also introduced

to the market.

A preview of 2010 and the

medium-term outlook

General economic indicators permit the

expectation of an end to the downward

trend in the western economic zone during

the current year with weak subsequent

growth starting from a low level.

The Asian economy, driven by Chinese

and Indian expansion, which will only

slacken slightly, will continue to grow in

the upper single digit area.

A comparable development is awaited

with regard to aluminum consumption in

20820

2008 2009 2014

Company

2010. On the basis of global demand for

rolled aluminium products of 15.6 million

tonnes (following 17.2 million tonnes in

2008), the CRU forecasts a 5 per cent

increase in the current year to 16.4 million

tonnes. AMAG order intake and demand

trends in the final quarter of 2009 already

showed initial indications of this development.

Accordingly, following a positive

start in the first few months of the year,

stabilization at a satisfactory level with

potential for sales volume growth is thus

foreseen for 2010. Secure access to primary

aluminium through the 20 per cent

holding in the Alouette smelter plant in

Canada is a steadying element in this connection,

especially with respect to longerterm

delivery contracts. The medium-term

forecasts for the development of demand

for rolled aluminium products continue to

be highly positive. Indeed, in the coming

five years growth from 15.6 million tonnes

in 2009 to 20.8 million tonnes in 2014

(+34 per cent) is forecast.

AMAG key figures 2009 2008

Sales revenues EUR m 517.4 781.9

EBITDA EUR m 108.0 124.3

EBIT EUR m 62.5 80.2

Other

China

Asia

Western Europe

North America

05

AluReport


06

Interview

“Process chain optimization

for top quality and resource

conservation”

AluReport recently discussed the

optimization of the entire process

chain and its importance with regard

to AMAG’s claim to premium supplier

status with the company’s CTO,

Helmut Kaufmann.

In its mission statement, AMAG

positions itself overall as a premium

producer. To what extent does this

also apply to AMAG casting?

To a very great extent, because when we

stress that the integrated production location

in Ranshofen constitutes a special

AMAG strength, this relates to the fact

that one cannot overstate the importance

of top quality working materials. The belief

that deficits from the cast house can

be compensated for during the rolling

process constitutes a massive error, for a

high-quality end product can only be created

when it is produced from first class

input material. In the case of AMAG casting

customers this applies both to our own

rolling mill, which processes ingots from

AMAG casting, and to the many casting

foundries that we supply with high-quality

recycling cast alloys. However, before we

go into detail may I first say something

regarding the definition of a premium

producer. At first glance, this term often

only conjures up images of special products,

but a premium producer must offer

a great deal more. All products have to be

manufactured in reproducible high quality.

A premium supplier must demonstrate innovative

strength, be constantly available

as a development partner and advisor to

customers and be able (and willing) to

react quickly to customer requirements,

conserve resources and keep environmental

impact to a minimum. The optimization

of these considerations has to cover the

entire process chain and therefore the

casting of cast and wrought alloys is an

essential element in AMAG’s strategy.

Let’s stay briefly with wrought alloys

for ingots. What contributes to the

premium claim in this connection?

Fortunately one cannot purchase a “premium”

label, one has to earn it. The three

main contributory factors are employee

competence, plant configuration and partnerships,

by which I mean both internal

and external. Alone the production of an

extensive portfolio of cast and wrought alloys

in AMAG casting’s two cast houses

brings a great deal, e.g. in the recycling

of diverse scrap for subsequent use in

wrought alloys. Joint sampling and coordinated

remelting enable us to employ

scrap, which is an important resource,

in an optimum manner. During alloy development

we cooperate with scientific

partners, and structural determination via

casting parameters and homogenization

takes place in the closest consultation

with our only customer in the rolling ingot

field, namely AMAG rolling GmbH. This

means that input materials are optimized

precisely in line with requirements.

Plant configuration plays an equally significant

role in success. We recently reported

in detail concerning our developments

in the field of melting and alloying

technology. These have even extended

to the development of our own rotors for

melt degassing in order to provide cleaner

melts. And naturally, we have developed

EMC technology (electro magnetic casting)

in the continuous casting area to an

especially high standard. The structural

quality available is globally unique and

EMC also allows the casting of ingots with

a high width to thickness ratio. In addition,

the resultant high cooling speeds allow

the realization of fine grains with microscopic

precipitation. No one else is currently

able to emulate this achievement

and apart from the fine grain, we have virtually

no segregation zones on the edge

of the ingot. This constitutes a quality advantage,

which particularly in the case of

high-alloyed materials, comes into its own

as edge fractures can be minimized. Our

latest developments such as the superplastic,

formable aluminium sheet material

AMAG TopForm ® SPF also benefit from

electro magnetic casting. All in all, with

the new electro magnetic caster, which

is presented in this edition of AluReport,

we have increased our capacity and set

a technological benchmark for the future.


What does the term premium

producer mean in the recycling cast

alloys area, especially with regard to

the automotive segment?

Our cast alloys are almost entirely produced

from scrap, but happily in this case,

the famous saying “garbage in, garbage

out”, which derives from computer simulation

and relates to entered data and

result quality, does not apply. We employ

scrap and obtain first class cast alloys as

products, which we then supply to our

customers in a variety of forms. Clients

can choose between liquid metal, bi-part

ingots, ingots from horizontal continuous

casting, or sows. However, what I see as

genuine progress is our ability to use the

potential of recycling cast alloys to a better

then ever degree. As a consequence of

intensive research, we have succeeded in

systematically defining and visualizing the

links between alloy composition and profile

of characteristics, which allows us to

provide our clients with improved consulting

regarding product-related, alloy selection.

By means of the resulting, innovative

AMAG TopCast Alloy Designer” software

tool, we are now in a position to systematically

design the most frequently used

recycling cast alloy, AlSi9Cu3, with regard

to increased strength, high elongation and

improved flow capacity, to optimize a possible

downstream heat treatment appropriate

to the material and thus open up new

fields of application.

Is the interplay between wrought

and cast alloy know-how useful in

this connection?

Yes. We have combined our R&D activities

in order to translate the know-how from

both areas into new developments. As a

result, we can even offer so-called nearprimary

recycling cast alloys in the liquid

metal sector, which only differ slightly from

conventional primary alloys due to their

iron content. Checks merely have to be

carried out to establish whether or not in

reality minimum iron content is needed for

every application. I have my doubts.

Look at the results from the work on the

AlSi9Cu3 alloy and you will understand

what I mean (please see the article on die

casting on page 10 of this AluReport). Notable

elongation can be achieved with iron

content of 0.4 – 1.2%. Moreover, in the

near-primary alloys, today we can even of-

fer 0.2 per cent iron as the lower limit for

alloys with high elongation levels. It is also

undeniable that with these near-primary

recycling cast alloys we have cost benefits

and clear advantages with regard to energy

and CO 2 balances.

Therefore, with an investment in a new

station for the filling of liquid transport

vessels, we have opened the door to new

applications. Indeed, we can now offer

increased capacity for the liquid transport

of both high potential, near-primary recycling

cast alloys with a low iron content and

wrought alloys.This pleases me greatly because

without doubt we have thus established

a new branch benchmark.

Thank you for the interview.

Answers to enquiries and demonstrations

of the “AMAG TopCast Alloy

Designer” are available at all times.

Simply contact our Sales Department:

casting@amag.at.

Interview 07

AluReport


08

Investments

EMC technology

raises quality and

cost efficiency

With the new electro magnetic (EM)

caster, AMAG casting GmbH has both

increased its capacity and established a

technological benchmark for the future.

Start of the first EMC plant in 1988

EMC (Electro Magnetic Casting) has established

itself as the cutting-edge technology

for the continuous casting of aluminium

alloys and recent development

work has further confirmed its outstanding

advantages for the 2xxx, 3xxx, 5xxx and

7xxx alloy groups. EMC began in the late

1960’s. At that time, a Russian team led

by Z. N. Getzlelev developed the continuous

casting of aluminium alloys in an

electromagnetic mould. Then in 1973, the

former Alusuisse purchased the Russian

patent licences and brought the process

up to large-scale production maturity. Subsequently

Alusuisse also bought the rights

to sell this technology to third parties and

in 1988, AMAG decided to obtain EMC

know-how and put a casting line into operation.

The main task of the plant was to

cast alloys susceptible to hot (3xxx, 5xxx)

and cold (2xxx, 7xxx) cracking in rolling

ingot sizes of 1,680 x 310 x 7,200 mm

(width x thickness x length). The subsequent

long-term operation of this caster

then enabled AMAG casting to acquire

comprehensive know-how in the field of

wrought alloys susceptible to hot and cold

cracking and on the basis of this experi-

ence, a second EMC system was installed

in 2009. This new caster allows the production

of rolling ingots with dimensions

up to 2,320 x 600 x 7,200 mm (width x

thickness x length).

EMC technology in brief

EMC can be generally classified as belonging

to the group of semi-continuous,

vertical continuous casting processes in

Water Chamber

µ m

60

40

20

Insulator

Inductor

EMC

Dendrite

Spacing

20 40 60

Screen

mm

View of the new EMC plant

which metal feeding takes place via a melt

distribution system consisting of a nozzle, a

plug valve and a glass cloth filter sack. The

contours of the solidifying metal are determined

in a water-cooled mould. During

conventional ingot casting, a pronounced

shell zone with a thickness of some 10-

20 mm is formed in the course of solidification

as a result of the direct contact of

the melt with the mould (please see Fig.

1 right). This shell is characterized by a

coarse cell structure and an inverse segregation

of alloying elements. Its thickness

increases in a linear ratio to the length of

the mould running surface (zone in which

direct contact between the mould and the

metal occurs) and this results in a large

amount of milling swarf prior to rolling.

In addition, mould lubricants (e.g. pastes

containing graphite, etc.) are needed in

order to ensure smooth casting [1].

Secondary cooling

µ m

60

40

20

Conventional

Dendrite

Spacing

20 40 60

Primary cooling

Fig. 1: Schematic diagram of the principles of conventional and electromagnetic casting,

including the progression of the dendrite arm spacings in the edge zones

mm


By contrast, EMC technology (please see

Fig. 1 left) employs an ideal continuous

casting mould, for as opposed to conventional

solutions, there is no contact

between the mould and the liquid metal.

The latter is kept in a suspended state by

means of electromagnetism derived from

a force field generated by high-frequency

alternating current. As a result, solidification

of the melt is contactless, which prevents

the formation of an inhomogeneous

shell zone. This means that by using this

technology, ingots with a very smooth

surface and a homogenous microstructure

can be produced. As a consequence,

usually no post-treatment involving milling

of ingots and edge trimming of hot rolled

strip is required [2-4].

Advantages of the direct combination

of EMC technology with the rolling

process

If one considers the economics of EMC

technology purely from the perspective

of the cast house, then a false, negative

picture could result. For as compared to

conventional casting technology, the EMC

process has a number of disadvantages:

• High investment costs

• Complex plant automation

• High running costs due to the electrical

energy requirement

• The need for comprehensive know-how

However, if one extends this limited field

of vision to include the further processing

phases included in subsequent

rolling, these problems can be clearly

counterbalanced. In the final analysis,

the economic advantages generated by

EMC technology are as follows:

• The reduction or avoidance of edge

cracking during hot rolling:

During hot rolling, conventionally cast,

hard alloy rolling ingots are subject to

highly prevalent edge cracking. This

leads to an increased volume of edging

scrap and a considerable reduction

in the working width of the hot strip.

Edge cracks derive from the presence

of a distinctive casting shell on the narrow

face of the rolling ingots. This reduces

surface strength and thus leads

to the formation of cracks caused by the

forces exerted during hot rolling.

The only help in this situation is the use

of an edge-milling device, but as a result

of limited throughput and increased

demand for material removal, this is uneconomic.

By contrast, owing to their

smooth cast surfaces, rolling ingots

derived from EMC technology do not

require any upstream edge milling.

• No necessity for milling prior to rolling:

No primary cooling is used in the EMC

technology. Therefor no separation

of the strand shell from the surface

of the mould takes place, which logically

enough also means that so-called

remelting of the already solidified strand

shell with the formation of a segregation

zone is avoided.

For these reasons, EMC rolling ingots

have a smooth cast surface and a cell size

that increases steadily from surface to

core (please see Fig.1) [4], which makes

surface milling unnecessary.

The enormous potential of EMC technology

can therefore only be exploited,

when as at AMAG in Ranshofen,

an integrated plant with cast house

and rolling mill is in operation.

The advantages discussed facilitate a remarkable

reduction in material removal requirements

at the rolling mill of up to 10 per

cent. In turn, this lowers the amounts of

internal cyclical scrap produced and eradicates

process steps, with the result that

major savings of both energy (melting of

the cyclical scrap and milling) and costs are

created. Therefore, if the cast house and

the rolling mill are considered jointly, the

higher investment and running costs relating

to the use of EMC technology in the

cast house are transformed into an economic

advantage in tandem with a simultaneous

improvement in product quality.

As a consequence, together with its

sister company, AMAG rolling, AMAG

casting is in a position to offer AMAG

customers a highly innovative product

that is both cost-efficient and ecologically

optimized.

To sum up!

As a result of the installation of a second

EMC technology caster, AMAG casting

Investments

Removal of the ingots from the casting pit

has succeeded in both extending top casting

quality to an enlarged product range

and strengthening its claim to be a premium

producer of rolling ingots.

Casting recipes for new alloys are being

continually created on the basis of longterm

experience and comprehensive operator

know-how. Moreover, an overview of

the complete process chain from the raw

material to the end product in the rolling

mill shows that the use of an EM caster for

numerous products (which were previously

cast conventionally) raises output, as milling

is no longer needed. Furthermore, the

new caster has facilitated an increase in

the thickness range from 310 to 600 mm.

Consequently, EMC technology from

AMAG casting creates the possibility of

producing a larger range of rolling ingots

with continuous casting quality of the

highest standard. This advantage is then

passed on directly to customers by the immediately

adjacent AMAG rolling GmbH

rolling mill in the form of innovative rolled

products.

Bibliography

[1] Schneider, W.: Stranggießen von Aluminium-

Werkstoffen. Stranggießen. Oberursel: DGM Informationsgesellschaft,

1995, p 3-20.

[2] Bermudez, A.; Muniz, M. C.; Salgado, P.: Asymptotic

approximation and numerical simulation of

electromagnetic casting. Metallurgical and Materials

Transactions B (2003), 34B, p 83.

[3]. Kim, S. W.; Hao, H.: Microstructure and fatigue

characteristics of direct chill cast and electromagnetic

cast 2024 Al alloy ingots. Metallurgical and Materials

Transactions A (2003), 34A, p1537-1543.

[4].Suppan, H: Operational experiences with electromagnetically

cast hard-alloy aluminium sheet ingots.

Erzmetall 44 (1991), No. 6, p 306-309.

[5]. Wagstaff, R. B.; Bowles, K. D.: Practical Loe

Head Casting (LHC) mold for aluminium ingot casting.

Light Metals (1995), p 1071-1075.

09

AluReport


10

Research

First class die casting quality due

to optimized alloy composition

and heat treatment

A profound knowledge of the complex effects of the most important alloying

elements is an essential prerequisite for top component quality. Hence the

integration of the latest know-how in the “AMAG TopCast Alloy Designer”.

AluReport 1/2009 contained an initial

report about ongoing research into the

optimization of secondary cast alloys to

meet specific requirements. The article in

question used the example of the A226

(AlSi9Cu3) alloy to provide impressive

clarification of the fact that in combination

with targeted adjustments to content,

the extensive alloy window offered by

the standard allows a very wide range of

characteristics. In particular, it was demonstrated

that iron as an alloying element is

not automatically detrimental as far as the

high elongation or good flow capacity of

a cast material are concerned, but rather

a)

b)

Elongation after fracture [%]

Elongation after fracture [%]

Fluidity [%]

Fluidity [%]

that the remaining alloying elements play

an important role [1].

Additional research has now examined the

influence of heat treatment on the characteristics

profile, as in the meantime all the

most important casting processes supply

products with so few gaseous inclusions,

that a solution heat treatment without bubble

formation is possible. As in the preceding

project, the content of the main alloying

elements, Si, Cu, Mg, Mn and Fe were

systematically varied within the standard

window. Characteristic evaluation took

place on the basis of tensile testing in a

Yield strength Rp 0.2 [MPa]

Yield strength Rp 0.2 [MPa]

Fig. 1: Mechanical characteristics and fluidity in a cast (a) and T6 (b) temper as a result of the

systematic variation of the chemical composition within the alloying limits. Heat treatment greatly

expands the characteristics range (blue: 0.4 % Fe, red: 0,8 % Fe; green: 1.2 % Fe).

T6 temper. The solution heat treatment

at 495°C for eight hours was followed

by a water quenching, interim storage of

the cast parts for 10 days at room temperature,

and hot ageing at 160°C for ten

hours.

Phenomenological evaluation

The high content of precipitation forming

and thus strength enhancing alloying

elements such as magnesium (max. 0.5

%) and copper (max. 3.5 %) permits the

expectation of a very wide window with

regard to strength and elongation values.

Fig.1 shows the spectrum of characteristics

for the cast and the T6 temper. Under

identical testing conditions, the yield

strength in the cast temper ranged from

approximately 100 MPa to roughly 200

MPa. With a T6 temper, the yield strength

increased clearly to levels between 135

MPa and just over 400 MPa [2]. As expected,

heat treatment also had a significant

effect on the elongation after fracture,

as while the cast temper values fluctuated

between 0.35 and 3.9 per cent, in a T6

temper, values between 0.15 and 7 per

cent were achieved. 7 per cent elongation

for the A226 alloy is already an outstanding

value and as the alloys had not been

refined, still more potential for an increase

in elongation after fracture remains. The

rise in the yield strength is not automatically

accompanied by a reduction in ductility.

Indeed, there are alloy variations for which

heat treatment results in considerable

increases in both the yield strength and

elongation after fracture. Because iron as

an impurity or alloying element is extremely

important to secondary cast alloys, Fig. 1a

and 1b also show the differences between

the alloy variations in accordance with iron

content. Both the F and T6 tempers permit

the expectation of a reduction of ductility in

line with increasing iron content.

The Modde diagrams shown in Fig. 2 provide

an informative picture of the effects

of the alloying elements magnesium and

copper.


Cu

Cu

3.4 3.4

340 340

3.2 3.2

320 320

3.0 3.0

300 300

2.8 2.8

280 280

2.6 2.6

260 260

2.4 2.4 240 240

220 220

2.2 2.2 200 200

2.0 2.0

0.1 0.1 0.2 0.2 0.3 0.3 0.4 0.4 0.5 0.5

Mg Mg

360 360 340 340 320 320 300 300 280 280

260 260 240 240 220 220 200 200 180 180

Research

Fig. 2: a) Yield strength in T6 temper T6 (9.5 % Si; 0.35 % Mn; 0.8 % Fe; 0.3 % Zn) b) Yield strength increase as compared with cast temper

The detailed definition of the influences of

the individual alloying elements and an indepth

metallurgical science interpretation

of the effects can be seen in [2].

AMAG TopCast Alloy Designer

Characteristics can only be adjusted in a

targeted manner when a precise knowl-

Fig. 3: MAGNA Powertrain housing components represent

a typical application of AMAG cast alloys

Cu

Cu

edge of the complex mechanisms of the

main alloying elements is available, otherwise

the extensive room for manoeuvre

available in the standard window brings

with it the danger of considerable fluctuations

in casting capability and mechanical

characteristics, which can lead to insufficient

component quality. Therefore, the

3.4

3.2

3.0

2.8

125.2

2.6

116

2.4

2.2

2.0

0.1 0.2 0.3 0.4 0.5

Mg

134.4

162

143.6

106.8

97.6

88.4

79,2

70

152.8

3.4

171.2

3.2

3.0

2.8

125.2

2.6

116

2.4

2.2

2.0

0.1 0.2 0.3 0.4 0.5

Mg

134.4

162

143.6

106.8

97.6

88.4

79,2

70

152.8

171.2

180.4 180.4 171.2 171.2 162.0 162.0 152.8 152.8 143.6 143.6 134.4 134.4 125.2 125.2

116.0 116.0106.8106.8

97.6 97.6 88.4 88.4 79.2 79.2 70.0 70.0

knowledge obtained during research has

been integrated into the new “AMAG

TopCast Alloy Designer”, a software tool

that furnishes the technical experts from

AMAG casting GmbH with the ability to

provide customers with optimized consulting

during the selection of compositions

within the 226 alloy range.

The definition in advance of the alloy-dependent

material and cast house characteristics

facilitates the selection of an optimum

alloy composition during an advisory

discussion, which accounts for both the

mechanical demands on the finished cast

component and special casting technology

factors.

The new data are of high practical relevance

to casting operators with regard to

the effects of heat treatment. For as can

be seen in Fig. 2 b, the attainable increase

in strength is highly dependent on composition

(up to approx.100 MPa difference!).

Indeed, with some alloy compositions, as

opposed to a cast temper, a T6 temper

can provide a doubling of strength!

Bibliography

[1]. P. Pucher, H. Böttcher, H. Kaufmann, H. Antrekowitsch

and P. J. Uggowitzer: “Einfluss der Legierungszusammensetzung

auf die mechanischen

Eigenschaften und das Fließvermögen der Sekundärlegierung

A226 (AlSi9Cu3)”, Giessereipraxis 3 (2009)

p 71 – 78.

[2] .P. Pucher, H. Böttcher, H. Kaufmann, H. Antrekowitsch

and P. J. Uggowitzer: “Einfluss der Legierungszusammensetzung

auf die mechanischen Eigenschaften

der Sekundärlegierung A226 (AlSi9Cu3) im

wärmebehandelten T6-Zustand”. Giessereipraxis 11

(2009), p 354 - 358.

11

AluReport


12

Research

AA 2024-T3/T351 alloy sheet

The influence of grain size on crack

propagation and fracture toughness behaviour

Modifications in grain structure facilitate

the further optimization of the

2xxx series with regard to fracture

toughness, crack propagation and

corrosion resistance, which is vital in

connection with maximum aviation

safety.

Introduction

2xxx-aluminium alloys are widely used in

aerospace applications because of their

excellent balance between high-strength

and low weight. Commercial jets are subjected

to cyclic loading during every flight,

as the cabin is repeatedly pressurized and

depressurized. Aircraft may be the object

of up to 100,000 such load cycles during

their normal service lifetime. Therefore, in

many aircraft components, resistance to

crack propagation under static and dynamic

loading conditions is essential. Numerous

advantages in this connection can be

realized by improving fracture toughness

and resistance to fatigue crack propagation.

In a recent publication Berneder et

al. examined both the influence of grain

size and shape on the damage tolerance

properties, and corrosion characteristics

in AA2024-T3 [1]. This article only discusses

the effect of grain size on fatigue

properties, but intergranular corrosion resistance

will be dealt with in a subsequent

issue of AluReport.

All the sheets investigated derived from

the same melt and had a chemical com-

Element Si Fe Cu Mn Mg

[%] [%] [%] [%] [%]

min. AA 2024 - - 3.80 0.30 1.20

max. AA 2024 0.50 0.50 4.90 0.90 1.80

Aktuell 0.08 0.11 4.32 0.44 1.43

Table 1: Actual chemical composition of the investigated material in weight % and AA 2024

tolerance limits.

Dassault Falcon jet

position identical to that shown in Table 1.

The sheet was produced using two differing

rolling and heat treatment cycles.

The EMC ingots (AMAG casting electromagnetic

casting) were hot rolled into strip

and then cold rolled to a final thickness of

1.6 mm. Temper “A” material was solution

heat treated on a continuous heat treatment

line at a temperature of just under

500°C with a soaking time of several

minutes, prior to being quenched to room

temperature with cold water. After cold

rolling, temper “B” material was additionally

annealed at a temperature of 300 -

400°C for 2 - 5 hours in a batch furnace.

After this intermediate annealing, like the

temper A material, the B material was solution

heat-treated.

Grain size and shape

A three-dimensional depiction of the different

grain sizes and shapes of temper “A”

and “B” material is shown in Fig. 1. Temper

“A” has a fine grain, globular structure, while

temper “B” demonstrates a coarse grain

structure elongated in rolling direction (L).


Temper Grain size [μm]

Elongation

ratio

L T S L/S

“A” 19 18 12 1.6

“B” 55 38 20 2.8

Table 2: Mean grain size of tempers “A” and “B”

in the L,T and S direction and the corresponding

elongation ratio

The grain size of both the “A” and “B” tempers

were measured in the L, T and S directions

as collated in Table 2.

Fatigue crack growth

The results of dynamic testing are shown

in Fig. 2.

The pre-notched sample used for the determination

of crack growth speed was

subjected to cyclical loads. The crack

growth speed (da/dN) for a certain step

width of the crack extension can be expressed

through the division of the change

in crack length (da) by the number of load

cycles (dN).

In general, both variations show a satisfying

crack growth rate, which makes the

materials suitable for aerospace applications.

However, the fatigue crack growth

rate in temper “B” is lower than in the finegrained

“A” temper. In addition, “B” shows

very similar crack growth rates in a T-L

and L-T direction and is therefore more

isotropic with regard to its fatigue crack

growth behaviour than “A”. Accordingly, as

far as crack growth is concerned, temper

“B” is to be preferred.

Two factors must be taken into account

when interpreting this phenomenon:

1) The reduction in the crack propagation

rate cannot be traced to differences in

fracture toughness for as shown in Table

3, both tempers demonstrate similar K c

values.

2) Grain boundary precipitation probably

plays a secondary role, as it is present in

comparable amounts and density in both

tempers [1].

Research

Fig.1 : (a) Three-dimensional diagram of temper “A” (fine-grained, globular); (b) Temper “B”

(coarse grained, elongated in rolling direction)

da/dN [mm/Cycle]

a)

a) b)

1.0E-01

1.0E-02

1.0E-03

Fatigue Crack propagation in T-L direction

1.0E-04

5 10 15 20 25 30 35 40 45 50

D K [MPa*m 1/2]

Type A, T-L direction

Type B, T-L direction

Typical Limit for Aircraft Skin Quality

“A” [MPa√m] “B” [MPa√m]

Kc 155.8 156.4

Kapp 98.7 99.4

Table 3 : Fracture toughness K and apparent

c

fracture toughness K for tempers „A“ and „B“

app

Status quo and the Outlook

AMAG 2xxx series alloys are widely used

in the aircraft industry, as well as in the

sporting goods sector and wherever high

strength at low specific weight is required.

AMAG covers all established 2xxx series

alloys (2024, 2014, 2017 and 2219) and

heat treatment tempers.

Every AMAG 2xxx product benefits from

the latest results of company research.

Indeed, by means of modifications to the

da/dN [mm/Cycle]

1.0E-01

1.0E-02

1.0E-03

Fatigue Crack propagation in L-T direction

1.0E-04

5 10 15 20 25 30 35 40 45 50

D K [MPa*m 1/2]

Type A, L-T direction

Type B, L-T direction

Typical Limit for Aircraft Skin Quality

Fig.2 : (a) da/dN-ΔK plot of temper “A” and “B” in the T-L direction; (b) da/dN-ΔK plot of state „A“

and „B“ in the L-T direction

b)

S S

T L T

L

grain structure, the dynamic fracture toughness

and crack propagation of AMAG 2xxx

series materials can be further optimized in

conjunction with a marked, simultaneous

improvement in general corrosion resistance.

In particular, these measures can

significantly enhance resistance to local

corrosion attacks such as intercrystalline

corrosion and thus contribute to increased

operational safety during utilization.

Bibliography

[1] J. Berneder, R. Rachlitz, C. Melzer, H. Antrekowitsch,

P.J. Uggowitzer: „Influence of the grain size on the IGC,

crack propagation and fracture toughness behavior of

AA2024-T3 sheet material”, Proceedings TMS 2010,

Seattle, USA

13

AluReport


14

Applications

Fig. 1: Bright product rolling mill at AMAG rolling

Top know-how for

bright products

AMAG is globally successful in the bright product segment, which is a suppliers’

market with only a few manufacturers. The highly demanding products involved

constitute a significant percentage of AMAG rolling’s overall production

volume and are therefore of major importance.

Decades of experience in a

challenging discipline

AMAG rolling disposes over more than

forty years of experience in the rolling

of aluminium. With the investment in a

bright product rolling mill in 1991 a new

era commenced in production, which until

then had been designed for a maximum

rolling width of 1,350 mm. In fact, new

bright product benchmarks were set as a

result of a bright mill width of 1,620 mm,

which is the widest in the world, and the

initial use of CVC technology (Continuous

Variable Crown) in such a unit. CVC is both

an electromechanical and hydraulic control

device, which serves the dynamic adjustment

of the rolling gap during the rolling

process through the axial shifting of the

work roller. In combination with the zonal

roller cooling, this creates outstanding flatness

even during rolling.

Just five years after the initial investment, a

second bright product rolling mill was started

up and this brought with it a further improvement

in surface quality with regard to

the degree of brightness and freedom from

defects. In addition, the product range was

extended in a high-end direction.

As a result of sustained market growth and

the ongoing consolidation of AMAG’s market

position, a decision was taken as early

as the autumn of 2001 to invest in a third,

special bright product rolling mill. On the

basis of the excellent experience gathered

with CVC technology, the new bright mill

was equipped accordingly. Following total

investments of over EUR 70 million in just

ten years, AMAG rolling now disposes over

the very latest equipment range and the

largest rolling capacity for this extremely

challenging product segment.

Special product know-how from

AMAG rolling

Of all the world’s aluminium rolling mills,

AMAG disposes over the most modern

technological capacity for bright products

(please see Picture 1). In combination with

experienced and motivated personnel, this

has resulted in a leading position in a diversity

of application areas. Due to the integrated

location in Ranshofen with its own

rolling ingot cast house, a complete range

of competence covering the entire value

added chain from the raw material, melting

and casting to thermomechanical treatment

is literally available under one roof.

Moreover, the in-company roller grinding

shop also provides an important element

in the provision of top, reproducible quality.

During roll preparation, roughness of less

than 1μm is adjusted and with the resulting

smooth rollers, even microscopic surface

irregularities on the surface of aluminium

strip are evened out mechanically, which

thus lends the metal a mirror shine. Should

a chemical surface treatment be required

for the end product, this is completed by

the AMAG customer.

All the materials of relevance to the surface

are cast by AMAG casting and then

examined for any casting-related deficiencies

prior to further processing in the

rolling mill. In combination with long-term

experience, the very latest casting technology

is a further critical factor in the

constant fulfilment of the highest quality

demands. Every process parameter is

stipulated within tight limits, subjected to

constant surveillance and registered. Plant

design, melt upgrading, filter systems and

all process controls have been optimized

for the casting of premium bright products.

In addition, the integrated location with

its short communications channels during

material changes and optimization allows

prompt and highly effective coordination

between the cast house and the rolling mill

for the perfect realization of customer requirements.

Occasionally contradictory customer demands,

like high strength material with

a bright surface can only be solved by a

creative combination of AMAG expertises.


As a rule, bright materials or those with a

brightness capability are either made from

pure aluminium, or are low alloyed, which

means that by definition, they are very soft.

Heat treatable alloys and high magnesium

alloys are either unsuitable for brightening,

or do not allow a suitable degree of brightness.

In such cases, AMAG can combine

its proven competence in the bright sheet

area with that from roll cladding, in order to

subsequently manufacture products with

customized characteristics.

In particular, roll cladding technology has

become established in the area of heat exchangers

and vehicle radiators. AMAG has

perfected this technology over many years

and today is able to roll bright strip and

sheets into a composite with other materials,

which answer the demand for strength

and surface quality in an outstanding manner.

As a result, material characteristics,

such as far higher strength values, can be

obtained that are superior to those available

in the monolithic materials normally

employed for bright products. Especially in

the case of soft cladding materials, which

have a purity of over 99.98 per cent, owing

to its higher strength, the alloyed core

material assumes this important function.

In addition, the use of a clad material saves

costs, as only the functional surface (depending

on the application 5-20% of total

thickness) is cladded with expensive, highpurity

material

Demanding applications

The bulk of the material produced is used

for reflectors. Moreover, following additional

surface upgrading by the customers,

in particular it is employed for louvers and

round reflectors. The material’s outstanding

reflective characteristics facilitate ener-

Fig. 2: Grain structure, polished cross-section

Fig. 3: Application as high-quality aluminum reflectors

gy savings and professional lighting management,

which allows the adjustment of

lighting to individual spatial and structural

requirements by means of high direct or

diffuse reflection.

As far as energy savings are concerned,

bright aluminium products are also utilized

in daylight control systems. Sunlight

is diverted into a building by means of a

redirection system and heat radiation is simultaneously

reflected, which lowers room

temperatures.

AMAG bright products are not only used

for reasons of cost-efficiency, but for energy

generation, as is the case with tube

collectors, parabolic trough power plants

and heliostats. They are also employed in

the field of photovoltaics as supplementary

reflectors for performance optimization. Interior

and exterior decorative elements in

aluminium serve to underline the high value

of cars and stand out due to their typical

haptics. In the automotive branch, aluminium

is irreplaceable as a design element,

especially in the premium segment. And

these outstanding characteristics are also

exploited in the electronics and household

appliance industries as they lend products

a still higher lifestyle character. A fact exemplified

by the covers on mobile phones,

Applications

digital camera housings and high-quality

coffee machines.

In both these market segments, AMAG

rolling combines the highest surface demands

with excellent forming characteristics.

Top quality signs and emblems continue

to be produced in anodized and painting

qualities, while the manufacturers of wellknown

luxury brands in the cosmetics sector

also use stylish, aluminium packaging

and thus rely on quality from Ranshofen. In

this connection, it is frequently the attractiveness

and originality of the packing that

represent a major criterion in the decision

to purchase.

Synergies between bright products and

other AMAG production possibilities

All other AMAG rolling products profit from

the cleanliness required for bright products,

the optimum handling of products undergoing

processing, and the surface-protective

packaging of coils and sheets. As a result

of the interplay with the know-how and experience

of the cast house, the rolling mill

is able to manufacture materials in the 6xxx

and 7xxx groups in anodizing quality. The

increased strength of these hardenable alloys

makes decorative components for the

electronics industry even lighter and more

resistant to damage during daily use.

15

AluReport


Group companies and locations

Austria Metall Aktiengesellschaft

P.O. Box 3

5282 Ranshofen

AUSTRIA

T +43 7722 801 0

F +43 7722 809 498

holding@amag.at

www.amag.at

AMAG operative companies

AMAG rolling GmbH

P.O. Box 32

5282 Ranshofen

AUSTRIA

T +43 7722 801 0

F +43 7722 809 406

rolling@amag.at

www.amag.at

AMAG service GmbH

P.O. Box 39

5282 Ranshofen

AUSTRIA

T +43 7722 801 0

F +43 7722 809 402

service@amag.at

www.amag.at

AMAG casting GmbH

P.O. Box 35

5282 Ranshofen

AUSTRIA

T +43 7722 801 0

F +43 7722 809 415

casting@amag.at

www.amag.at

Aluminium Austria Metall (Québec) Inc.

1010 Sherbrooke ouest

# 2414, Montréal, QC. H3A 2R7

CANADA

T +1 514 844 1079

F +1 514 844 2960

aamqc@amag.at

www.amag.at

AMAG rolling GmbH sales subsidiaries

AMAG Deutschland GmbH

Mülheimer Str. 43

47058 Duisburg

GERMANY

T +49 203 393780 0

F +49 203 393780 20

amag.deutschland@amag.at

AMAG ITALIA S.r.l.

Via Pantano 2

20122 Milano

ITALY

T +39 02 720 016 63

F +39 02 720 942 54

amag.italia@amag.at

AMAG BENELUX B.V.

Galgkade 3b

3133 KN Vlaardingen

NETHERLANDS

T +31 10 4604499

F +31 10 4600809

amag.benelux@amag.at

AMAG U.K. LTD.

Beckley Lodge

Leatherhead Road

Great Bookham

Surrey KT 23 4RN

UNITED KINGDOM

T +44 1372 450661

F +44 1372 450833

amag.uk@amag.at

AMAG metal GmbH

P.O. Box 36

5282 Ranshofen

AUSTRIA

T +43 7722 801 0

F +43 7722 809 479

metal@amag.at

www.amag.at

AMAG FRANCE SARL

65, Rue Jean Jacques Rousseau

92150 Suresnes

FRANCE

T +33 141 448 481

F +33 141 380 507

amag.france@amag

AMAG USA Corp.

600 East Crescent Ave, Suite 207

Upper Saddle River

NJ 07458-1827, USA

T +1 201 9627105

F +1 972 4991100

amag.usa@amag.at

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