Cobalt-base high-temperature alloys

We have identified cobalt-base superalloys showing a high-temperature strength greater than those of conventional nickel-base superalloys. The cobalt-base alloys are strengthened by a ternary compound with the L1(2) structure, gamma ' Co-3( Al,W), which precipitates in the disordered gamma face-centered cubic cobalt matrix with high coherency and with high melting points. We also identified a ternary compound, gamma ' Ir-3(Al, W), with the L1(2) structure, which suggests that the Co-Ir-Al-W-base systems with gamma + gamma ' (Co, Ir)(3)(Al, W) structures offer great promise as candidates for next-generation high-temperature materials.