均匀化处理对Ni3Al基MX246A合金热压缩塑性的影响

Effect of Homogenization on Hot Compression Ductility of Ni3Al-Based MX246A Alloy

摘要:

在MTS试验机上研究了不同均匀化工艺对MX246A合金热压缩塑性的影响。结果表明，随着均匀化温度的升高和均匀化时间的延长，MX246A合金的热压缩塑性和均匀性增加；采用1160 ℃保温24 h+1230 ℃保温48 h的均匀化工艺后，变形量达到80%时，MX246A合金变形仍较为均匀，表面质量良好。经过微观组织的分析发现，绝热剪切带的形成引起MX246A合金在压缩过程中失稳；晶界和枝晶间的γ′相包覆碳化物的复合组织强化、成分偏析的减轻是均匀化后MX246A合金热压缩塑性提高的主要原因。

Abstract:

The effect of different homogenization treatments on hot compression ductility for MX246A alloy was investigated on MTS test machine. The results show that hot compression ductility and uniformity of MX246A alloy increase with elevating homogenization temperature and prolonging homogenization time; homogenized at 1160 oC for 24 h + 1230 oC for 48 h, MX246A alloy could be compressed for 80% reduction with uniform deformation and good surface quality. The microstructure observation reveals that the compression destabilization of MX246A alloy is caused by adiabatic shear band, and the enhancement of hot compression ductility is mainly contributed to the alleviated segregation and the strengthening of carbides enveloped by γ′ phase.