Alloy Development
Over the last 20 years Wah Chang
has played a major role in the development and production
of a wide variety of zirconium, niobium, tantalum, vanadium
and specialty titanium alloys for the nuclear and aerospace
industries. The company’s success in this field is often
linked to its ability to maintain high levels of alloy purity.
In other cases, Wah Chang's
ability to evaluate a wide variety of melting and fabrication
process unique to refractory metals has been a key to its
successful development of new materials. Over the last ten
years, the company's diversifying product lines and customer
base have demanded a continual use of all of its alloy development
capabilities. Consequently, Wah Chang maintains a team of
personnel and associated equipment specifically devoted to
developmental melting and fabrication of refractory metals.
The company routinely provides these services to aerospace
and nuclear companies as well as laboratories worldwide. In
the last several years, personnel have prepared dozens of
experimental alloys. Some of these include advanced zirconium,
vanadium, and niobium alloys for the nuclear industry and
titanium aluminides, niobium aluminides, as well as refractory
base alloys for hydrogen storage.
Composition and microstructure
of all materials can be evaluated at Wah Chang. Its physical
property measurements, including hardness, bending, and tensile
testing at room temperature and at elevated temperatures up
to 1316°C (2400°F) under high vacuum.
Wah Chang's R&D laboratory is also equipped for development
of high-temperature fabrication parameters for refractory
metals. Pilot scale ingots weighing 5 to 25 kg can be forged
and hot rolled at temperatures up to 1600°C. Lab-scale hot
working equipment includes a 3.5 MN (400-ton) controlled strain
rate (0-30mm/sec) forge press and a 300-mm (12 in.) wide universal
rolling mill. Extrusion, cold rolling, wire drawing, as well
as swaging facilities are also available. Processing parameters
for new alloys are often investigated on a pilot scale with
these facilities prior to attempting fabrication of larger
production-size ingots.
In addition to its powder processing
facilities for manufacturing special alloy powders, Wah Chang’s
R&D lab is capable of developing specialty powder metallurgy
products. Parts developed in the laboratory include fully
dense zirconium alloy nuts and valve parts for the chemical
process industry. Other R&D products include porous zirconium
filters and porous niobium alloy wicks for liquid metal heat
pipes. Wah Chang’s zirconium and niobium alloy powders
can be consolidated by hot or cold isostatic processing, mechanical
pressing, and vacuum sintering up to 1650°C (3000°F). When
required, Wah Chang uses completely inert gas handling to
eliminate pyrophoricity problems and to minimize powder contamination.
Using the hydride-dehydride process, personnel routinely make
small quantities (1 kg to 50 kg) of custom alloy powders.
If your organization requires
custom-made refractory alloys, Wah Chang’s experienced
staff is ready to help. Contact us for more information on
the company’s alloying capabilities and support services.
TABLE 3.
The above elements are typical metals purified and alloyed
by EB melting.
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