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Heat treatment process for Ni3Al- based wrought superalloy

Influence of solution treatment temperature on microstructure and high- temperature tensile properties of Ni3Al- based alloy sheet was investigated. The results show that volume fraction of ?? phase reduces and volume fraction of ?á?+?? region increases with increasing heat treatment temperature up to 1280??. When the temperature reaches to 1310??, volume fraction of ?á?+?? region keeps at the same level but that of ?? phase increases. Due to precipitation of ?? phase along grain boundary with the temperature raising, grains begin to grow up until the temperature reaches 1280??. The grain sizes are different for different directions at the solution treatment temperature below 1280??. Crack initiates at the interface of ?? and ?á? envelope during 1000?? tensile test. The increase of volume fraction of ?á?+?? region can increase the strength of the alloy. The alloy has excellent comprehensive mechanical properties after heating at 1280?? for 16min and AC.