COST 507 - Repositório Aberto da Universidade do Porto

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Today there is a whole range of instruments with which nearly all of the features across this range can be made visible. In this sense one may use the term continuous materialography [14]. The higher the requirements of a material, the more stringent are the requirements on its microstructure, i.e. the more accurately must its m i ero structure be established. The aim is to be able to create a microstructure specifically designed to produce a given property profile. The terms "microstructural engineering" and "microstructural design" are the keywords used to describe this process. Only in this way can the strictyl defined materials needed for stringent operating conditions and close property tolerances be realized. Typical contemporary examples are the oxides, nitrides, carbides and borides. These chemical compounds have been known for a long time, but it is only recently that they have been turned into advanced ceramic materials exhibiting useful properties. The prerequisite for this was a procedure to design a well-defined, fine-grained microstructure. How marked this detailed characterization of the morphology of a microstructure can be, can be seen in Fig. 12 as an example. Scanning electron micrographs are shown of the microstructure of an alumina-zirconia alloy. , as well-known cutting tool material. Both samples have the same composition. The light particles are zirconia inclusions in the alumina matrix, which appears gray. Both samples were prepared by densification of the same starting material. However, different densification processes were used. Although the treatments applied did not differ greatly, a large difference in strength resulted - nearly a factor of two The reason for this is a minute variation in the microstmcture. The treatment of the sample shown on the left resulted in a more pronounced grain growth, and as a direct consequence of the microstructural coarsening, the strength decreased markedly. The advanced ceramic materials, chosen as an example to convey a feeling and understanding of the significance of microstructures, have experienced a fascinating boom in the last few years and more breakthroughs can be expected in the future. The possibility of optimizing new materials by microstructural leads us to thoughts on the realization of novel materials and their availability. 38
NEW MATERIALS After all recent developments of new materials, the question as to the potential of further materials arises. Can we hope for significant new contributions, especially if we consider the great multitude of materials already available? The answer is straight-forward: yes! In fact, potential materials are in abundance and the possibilities of combining and varying elements are almost unlimited even though there are just over 100 elements. The following considerations may help to clarify this: Elements can be mixes or alloyed respectively and combined to systems, for instance the well-known iron-carbon system, which involves many carbon steels and cast irons. Let us consider 86 of the 100 or so elements we know, and ignore inert gases and the transuranic elements. If we combine these 86 elements to binary, ternary, quaternary systems and so on, up to the 86-element system, the total number of possible systems comes to as many as 7.7 χ 10" ! In Fig. 3 the number of possible systems is plotted as a function of the number of elements N. This can be drawn only on a logarithmic scale, otherwise the ordinate would extend to the Milky Way. We have only 86 unary systems (the elements), 3.655 binary systems, more than 100.000 ternary systems and so on and the maximum of 6.6 χ 10" systems is reached with 43 elements. Beyond this maximum the number of possible systems decreases and finally only 1 system with all 86 elements exists (which contains all other systems as subsystems). On the other hand, the number of systems investigated decreases steeply as the number of components increases. Altogether about 10.000 systems are known to date, most of them only partially. This is marked by the hatched area in Fig. 3. This area represents all known materials. The ratio of known to possible systems is as small as 10*"". This "mountain" of materials shown in Fig. 3 is hardly accessible in reality and represents a huge reservoir of materials. Despite the numerous combinations of elements used in today's materials, a much larger multitude of unknown possibilities remains. Among these could be numerous technological material combinations, which some day could play a role similar in importance to today's steels, superalloys, advanced ceramics and so on. - 39
Page 1 and 2: European Commission COST European c
Page 5 and 6: European Commission COST European c
Page 7: Preface The Final Workshop of the C
Page 11 and 12: COST 507 STRUCTURE Measurement and
Page 13: GRl: Mirtee S.A., Volos Mr.P.Polati
Page 16 and 17: D9 Dll Fl GR2 II NI S3 SF1 "Thermop
Page 19 and 20: A Summary of the COST 507 Action an
Page 21 and 22: Aluminium-based systems Titanium-ba
Page 23 and 24: An Example using the COST 507 Datab
Page 25 and 26: Appendix COST 507: Some Key Meeting
Page 27 and 28: Al - 0.5 Fe, 1 Mg, 0.8 Mn, 0.2 Si (
Page 29 and 30: Fig 4 Aluminium beverage cans. The
Page 31: Fig 6 High pressure compressor vane
Page 34 and 35: INTRODUCTION All of us are aware of
Page 36 and 37: In the interaction with materials a
Page 38 and 39: There was a first warning more than
Page 40 and 41: Some time ago, the well-known physi
Page 44 and 45: The dimension of this reservoir inc
Page 46 and 47: REFERENCES [ 1 ] G. Petzow, "Man, M
Page 48 and 49: Trends in Application of Materials
Page 50 and 51: Raw Materials The Cycle of Material
Page 52 and 53: i LÌ i.'»Af·· iù^ VV.V.X. iTTa
Page 54 and 55: 1600 OJ 1200 .« 1100 d 1000 900 Si
Page 57 and 58: Al Phase Relations in the Aluminium
Page 59 and 60: oundaries of the single phase regio
Page 61 and 62: Table 1 : Crystallographic Data of
Page 63 and 64: order to facilitate the evaluation
Page 65 and 66: (especially around 33 at% Mg) in or
Page 67 and 68: 3.System Ti-Sn-Al-N. The investigat
Page 69 and 70: 6) N.Durlu, U.Gruber, M.Pietzka, H.
Page 71 and 72: Summary of final report Directional
Page 73 and 74: calculate the thermodynamic mixing
Page 75 and 76: Introduction It is the aim of this
Page 77 and 78: Thermodynamic evaluations for high
Page 79 and 80: Figure 5 presents the calculated li
Page 81 and 82: There is a complete lack in the lit
Page 83 and 84: a.B5 ø.ia 0.15 0.20 0.25 0.30 0.35
Page 85 and 86: 700 [53Phi] 800 +[90Kuz21 ]iquld a
Page 87 and 88: Thermodynamic Assessments, Experime
Page 89 and 90: AIN and TiNi_ x is also given. Vari
Page 91 and 92: satisfied the three requirements of
Page 93 and 94:
84Bey R. Beyers, R. Sinclair, and M
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Material and Methods 2.1 Fabricatio
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3.4 Electronmicroscopy (SEM) and X-
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Tab. 3: Density of the Ti20Albase
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Tab.5. continued TÌ20A1 5CulONi Ti
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Fig. 3: ESMA and Xray diffraction
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Fig.7: Wetting angle of Ti 15A1 lOC
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Thermophysical Properties of Light
Page 109 and 110:
Tab.2 Chemical composition of terna
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700 (AI)+AIFeS¡«_600 KS1275.1 l
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4.2 Thermal conductivity of industr
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4.3 AlSiZn alloys Electrical re
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94Jar/Bra G.Jaroma-Weiland, R.Brand
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MgZn9 (C 14) and Mg2Zn u in the Al
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The three Laves phases were describ
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References [13Ege] G. Eger, Z. Meta
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0.30 0.35 0.40 0.45 0.50 mole fract
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□ [48Koe] 600 500 400 0 0.1 0
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MggZn,, this work □ Single phase,
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Temperatures in °C 0.05 0.10 mole
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Table 2 : Alloy compositions Alloy
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All. Dy 50 Cpexp °C Cpadd Table 5
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Zn ¿Kl Si Fig. 2 : Position of the
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22.5 ■■ 7.5 Temperature ICI Tem
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.to 2.5 "lõõ soo iÍOõ dOõ rtõ
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GR2 Differential Scanning Calorimet
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Time (x10 3 sec) Fig. 1. DSC Thermo
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solidification. It can be seen that
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4. Conclusions Differential scannin
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COST 507 - ROUND Π UNIT II SEZIONE
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[96Sac] The Rrich regions of the
Page 155 and 156:
List of publications in the framewo
Page 157 and 158:
2Contributions: oral or posters p
Page 159 and 160:
1996 REPORT 2 s ' PART: ACTIVITY CA
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[96Sei] Excess Gibbs energy coeffic
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List of publications in the framewo
Page 165 and 166:
Proc. :7 th Meeting on "Syntheses a
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2.1 Solid solubility measurements T
Page 169 and 170:
eviews by Rivlin and Raynor [81 Riv
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inaires. Thesis, Universite Scienti
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Table 1. Review of the ternary phas
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L) Liq+bcc=FeSi+t_1 M) Liq+t 1=FeSi
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Extrapolations based on Ti-C-N S3 B
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value has been accepted in all thre
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with high precision whereas Jonsson
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only fit the hightemperature asym
Page 185 and 186:
Jonsson combined his descriptions o
Page 187 and 188:
Table II. Solubility product of TiC
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Ti-C, Z.Metallkd. 86 (1995) 5 319
Page 191 and 192:
1000 1500 2000 2500 3000 Τ (K) Fig
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o Oí o 3 4 5 6 7
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M^øD^ O Kelley(1944) • Kelley an
Page 197 and 198:
— cale, with Dumitrescu (1997) -
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€ gfc-π m-, .-π-, π-π .-saa J
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+graph 0 TiN 0.2 0.4 0.6 X TiC 0.8
Page 203 and 204:
Binder et al (1992) TiN 1423 K ■
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0.08 600°C 700°C 800°C 900°C 10
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[59Sto]: Ä600°C □ 70D°C O8Q0°
Page 209 and 210:
2000 Cale, with Saunders (1997) —
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An Experimental Investigation of th
Page 213 and 214:
An Experimental Investigation of th
Page 215 and 216:
211 -
Page 217 and 218:
EXPERIMENTAL INVESTIGATION OF THE C
Page 219 and 220:
Fig.1 SEM micrographs of CuMgZr
Page 221 and 222:
■ 888 24 HSM^«" 16—19 3 À I
Page 223 and 224:
Thermodynamic Evaluations of the Al
Page 225 and 226:
Fcc_Al aves_C15 ONU ΔΝ12 αΝ13
Page 227 and 228:
2.2 Assessment The optimisation of
Page 229 and 230:
0.50 0.45 CulOZr7/ 0. 40 Or ^ 0.3
Page 231 and 232:
References [71Kri] Kripyakevich, P.
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Kejun Zeng and Marko Hämäläinen,
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for detennining phase boundary and
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Table 2 Al-Fe-Mn results wt%Fe 0.5
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•00 Γ Ι I I I ~ LIQUID S^ 7iO
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the observed A2-B2 ordering. This p
Page 243 and 244:
1473K Ahmed & Flower [94 Ahmi] 0.2
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900K Paruchuri & Massalski [91Par]
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BCC_B2#2 TI3RL TIPL BCC B2#2 TIRL
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0.2 0.3 0.4 0.5 X(LIQ,V) Figure 15
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1 Introduction and Overview of the
Page 253 and 254:
at least 95% by Fe, possibly 99%, a
Page 255 and 256:
8 References 43Phi H W L Phillips,
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1050 1000 Isopleth, Al - Si - 4 wt
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Al-Mn-Si 873 K 0.90 Liquid 0.80 0.7
Page 261 and 262:
A Thermochemical Assessment of Data
Page 263 and 264:
certainly due to the appearance of
Page 265 and 266:
Materials Science Centre, November
Page 267 and 268:
1400 Al-Mn Fig 2 Calculated partial
Page 269 and 270:
1000 ι AlMn I Ι 950 Liquid E ω
Page 271 and 272:
Al-Fe-Mn 843 K 0.90 0.80 0.70 0.60
Page 273 and 274:
AlFeMn section at 2 wt% Mn co
Page 275:
0.50 0.45 0.40-1 LU £ 0.35 LU 0.30
Page 279:
European Commission EUR 18171 —CO
Page 284:
NOTICE TO THE READER Information on
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