To help electric companies generate fewer greenhouse-gas emissions, alloy producers have been developing nickelbased superalloys.
These materials let land-based turbines run hotter and, thus, generate electricity more efficiently. Hotter combustion also helps keep ozone-depleting emissions in check.
Haynes International Inc., Kokomo, Ind., for example, has developed an advanced, wrought gammaprime strengthened superalloy called Haynes 282. It stands up well to strain-age cracking, a problem common to many gamma-prime strengthened alloys. The 58Ni-19Cr-10Co-8.5Mo-1.5Al-2.1Ti alloy is also a candidate for aircraft manufacturing and other high-performance, high-temperature environments. Reports indicate the alloy is stronger in creep strength than N07001 (Waspaloy) and approaches the creep strength of N07041 (Haynes R-41) at temperatures as high as 1,650°F (900°C). Further, the 282 alloy is easier to weld and fabricate compared to Waspaloy and R-41 alloys.
|PHYSICAL PROPERTY COMPARISON|
Haynes R-41 (N07041)
|Thermal conductivity, Btu-in./ft2-hr-°F|
|Mean coefficient of thermal expansion, μin./in.-°F|
70 to 800
70 to 1,200
70 to 1,600
70 to 1,800
Haynes International Inc., (765) 456-6012, haynesintl.com