POWER UP A WINNER - Plant Services

Technology Toolbox
Sheila Kennedy
Alternative Materials
High-tech options have steel, brass, copper and other metals on the run
Scientists, engineers and manufacturers are expanding
the choices for material of construction. They’re
eliminating nano-scale flaws that promote corrosion,
impregnating alloys to enhance bearing properties, developing
copolymers that enhance performance, and leveraging
amorphous metals and thermoplastics for new applications.
Alloy refinements: Oxide scale that forms on steel alloys
at high temperatures defends the metal from corrosion, but
some carbon can get through. Scientists at the U.S. DOE’s
Argonne National Laboratory detected a nano-scale flaw
that allows carbon to dissolve and diffuse through the oxide
scale and cause brittleness and corrosion.
Argonne eliminated the iron and nickel nanoparticles and
developed alloys that are more corrosion-resistant and exhibit
as much as 10 times longer life than commercial alloys
of similar chromium content. When commercialized, this
could reduce costs for the chemical, petrochemical and refining
industries. The findings can influence metal dusting,
carburization, alloy development and surface coatings for
high-temperature industrial as well as fuel cell applications.
Sulfonated copolymers: These structures can provide a
lower-cost, high-performance material for breathable protective
clothing, sensor, actuator, filtration, energy-recovery
and antifouling applications. The sulfonated copolymer
technology in Kraton Polymer’s MD9150 and MD9200
products exhibit water vapor transport, ion exchange,
chemical resistance and gas permeability. The structure
reduces processing temperatures, which saves energy. Kraton’s
products are suited for wet and dry environments, and
will be offered in membrane and solution forms for use in
shapes, coatings and laminates.
Babbitt impregnation: Materials that combine carbon’s
hardness and wear resistance with graphite’s self-lubricating
properties and babbitt’s resistance to galling led to hightemperature
bearings. Metallized Carbon Corp.’s oil-free,
self-lubricating high-temperature bearings (to 350°F ) made
with Metcar grades M-161 and M-162 materials exhibit
stability and strength They won’t score the mating shaft and
provide continuous lubrication for their service life. The
materials are applicable to mechanical components used
in elevated-temperature applications where conventional
lubricating methods are impractical.
Amorphous metals: A material more durable than silicon
and stronger than steel shows promise for the manufacture
of nano-devices. Yale engineers developed amorphous metals
– bulk metallic glasses (BMGs) with no structure beyond
the atomic level – for molds that imprint fine details from
13 nanometers to several millimeters. Grain size limits the
level of detail imprinted. BMGs an be molded like plastics
and are more wear-resistant than metals at normal working
temperatures. Template molds made from this material are
A MATerial more durable than silicon
and stronger than steel shows promise
for the MAnufacture of nano-devices.
long-lasting, reliable and cost-effective. Nano-molds, -wires
and -gears have been fabricated by molding metallic glass.
Engineered thermoplastics: These provide a safe, costeffective
alternative to copper, stainless steel and brass water
valves for fluid-handling systems. Copper theft is a growing
crime and the lead in brass alloys is a health hazard. From
a design perspective, thermoplastic can be integrated into a
single part, but metal involves assembling multiple parts.
SABIC Innovative Plastics offers engineered thermoplastics,
including Noryl and Ultem amorphous resins and LNP
Lubricomp compounds. Noryl and Ultem creep less than
semi-crystalline thermoplastics and preserve dimensions
and valve sealing abilities. Noryl GFN1430V resin reduces
fatigue and damage caused by pressure fluctuation because
thinner wall sections are possible. The Noryl polyphenylene
oxide (PPO) has better hot-water resistance than semicrystalline
resins. SABIC’s Fluid Engineering Center of
Excellence offers access to testing equipment and scientific
resources to assist in developing fluid-handling solutions.
E-mail Contributing Editor Sheila Kennedy, managing director of
Additive Communications, at Sheila@addcomm.com.
Reference Web sites:
www.anl.gov
www.metcar.com
www.kraton.com
www.yale.edu
www.sabic-ip.com
www.corrim.org
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