η相对沉淀强化奥氏体合金持久性能的影响

Effect of η phase on stress rupture property of precipitation strengthened austenitic alloy

研究了晶界η相(Ni3Ti)对沉淀强化奥氏体合金不同温度、应力下持久性能的影响。结果表明,晶界η相对合金持久性能影响较大。低温高应力下,晶界η相通过促进晶界处应力集中引起开裂,降低合金持久寿命及塑性;高温低应力下,η相通过阻碍晶界滑动及迁移,显著提高合金的持久塑性。

Effect of η phase on stress rupture property of precipitation-strengthened austenitic alloy was investigated. The results show that the stress rupture property is influenced remarkablely by η phase. At low temperature and high stress condition, the η phase will induce the stress concentration at grain boundary which promotes the origin of microcrack, and decrease the rupture life and ductility. However, at the high temperature and low stress condition, the η phase can prevent grain boundary from slide and moving, and the rupture ductility is improved.