ThyssenKrupp Magazin

must be no mix-up, so not one of the metal blocks stored in the smelter
hall and the yard is without a nametag.
What flows from the casting chute into the furnace is processed
into strips, bars, wires, sheets and foils, though this does not happen
immediately in Unna. Some materials leave the building as glowing
blocks in special transporters – they take with them part of the immense
heat energy through which they were created. Further processing is a
competition against temperature: in the Duisburg plant the chrome
steel blocks are rolled into plates measuring 8 to 9 meters, though that
is only a transitory stage. After that, the plates are transported to
Ruhrort for sanding and then to the Bochum plant, where they are
processed into four-millimeter-thick strips – at a residual temperature
that remains at 300 degrees Celsius.
A MATERIAL THAT REVOLUTIONIZES THE AUTOMOTIVE WORLD
The final product – Aluchrom 7AI YHF – is a new creation that emerged
from a federal research product and was awarded the environmental
protection prize by the BDI, Germany’s main industrial association. The
material, which is amalgamated with such foreign elements as yttrium
and hafnium, is used to produce foils with a thickness of 30 to 40 micrometers.
These are key components of modern metal catalysts for automotive
engines, which have considerable advantages over ceramic,
the classical carrier material; thanks to their fast heating, they are al-
The materials with the
toughest requirements have
to go through the fire three
times - only then do they reach
the highest level of purity.
What flows from the casting
chute into the furnace
is processed into foils, bands,
bars, wires and sheets.
TK Magazine | 1 | 2004 |
Alloys from the finest smelter
VIM FURNACE 91
ready fully effective in the start phase. The products concocted in Unna
are among the most precious around, and are turned out in significant
volumes. In 2002, more than 32,000 tons of nickel basis alloys were
supplied, a third each to Germany, Europe and the United States. In the
nickel segment, which was launched with coinages in the mid-19th century,
ThyssenKrupp VDM is the world market leader. Added to this must
be about 5,000 tons of special precious steels per year. Unna even helps
ensure a pleasant evening in front of the television, since high-value
shadow masks in cathode ray tubes are made of the special alloy
Pernifer 36; they resemble a sieve with holes spaced 20 micrometers
apart, a magnitude that the human eye basically cannot perceive. The
material hardly stretches under high temperatures and thus allows for
the creation of sharp color dots on the screen. Pernifer 42, meanwhile,
serves as a carrier material for integrated switches, while Conicro 5010
W is a heat-resistant material used in the thrusters of the Ariane rocket.
The director of the Unna works, Dr. Jürgen Loh, who holds a doctorate
in engineering, is a very competent guide through the amazing
maze of high-performance materials, and one who enjoys painting the
possibilities of the future. Crofer 22 APU, he points out, is an entirely
new iron-chrome alloy characterized by tremendous heat resistance,
conductivity and a low stretch coefficient – an ideal material for the serial
production of fuel cells, the revolutionary power system expected to
revolutionize the automotive world. 7