Fresh from NASA: Aluminum tough enough for high-temperature casting
|Jonathan Lee prepares to test the strength of the new alloy he coinvented at NASA's Marshall Space Flight Center, Huntsville, Ala. The high-strength aluminum-silicon could help lower engine emissions and improve gas mileage in cars, boats, and recreational vehicles.
Dubbed MSFC-398 or NASA High-Strength Alloy, it performs well at superhigh temperatures. Testing at 600°F reveals it is three to four times stronger than conventional cast-aluminum alloys. It can also be poured as a molten metal into traditional steel and die-casting molds to create complex parts. And a pound of the material costs less than $1.
"The alloy is ideal for high-temperature cast components such as pistons, connecting rods, actuators, brake calipers, and rotors," says Jonathan Lee, NASA scientist and coinventor of the new metal. He foresees the alloy helping designers meet lower emission standards. For example, one approach being studied involves minimizing piston-crest volume, the air gap between the piston wall and cylinder bore. Engineers want to move the top piston ring closer to the top of the piston crown. A strong, low-cost alloy like MSFC-398 makes this possible by letting pistons have less crown depth, but remain strong enough to withstand high work and heat loads.
"NASA High-Strength Alloy offers the greater wear resistance and surface hardness that will let manufacturers use less material, thus reducing weight and cost while improving gas mileage and engine performance and durability," says Lee.
The alloy has earned NASA two patents and the organization has licensed several companies to develop it into new products. The companies include Advanced Material Technology Inc. and Eck Industries (www.eckindustries.com), both in Manitowoc, Wis., and Swan Metal Composites Inc., Woodinville, Wash.