含碳镍基单晶高温合金的再结晶倾向性

Recrystallization in a Single Crystal Superalloy with Carbon Addition

研究了不同碳含量镍基单晶高温合金在不同固溶温度和压应变条件下的再结晶倾向性。结果表明:铸态γ′相的溶解是再结晶晶粒形成的重要条件;再结晶层厚度随固溶温度的升高而增大;随着应变量的增加,再结晶晶粒增加;热处理时间越长,则再结晶越容易发生;γ/γ′共晶、大γ′相和碳化物均具有阻碍再结晶生长的作用;在该合金系中碳无明显改善再结晶倾向性的作用。

The recrystallization tendency of single crystal superalloys with different levels of carbon at different solution temperatures and compressive stresses was investigated. The important condition for recrystallized grain formation is the solution of γ′ as-cast state. With the rise of solution temperature, the thickness of recrystallized layer increase. With the expanding of compressive strain, recrystallized grain number increase. The longer the heat treatment time, the easier the re.crystallization. The γ-γ′ eutectic, large γ′ phase and carbide could all inhibit the growth of recrystalllzed grain. The addition of carbon has no effect on suppression of recrystallization.