调幅分解程度对Ni-32%Cu合金形变织构的影响

Effect of spinodal decomposition degree on deformation texture of Ni-32%Cu alloy

采用等离子弧熔炼和真空感应重熔的方法制备了Ni-32%Cu合金坯锭,经热锻、热轧及退火得到实验用合金,将其置于350℃下保温0、1.5和4.0 h获得了3种不同调幅分解程度的Ni-32%Cu合金。这些合金经过总变形量为98%的冷轧后,采用X射线四环衍射仪,研究了调幅分解程度对Ni-32%Cu合金形变织构的影响。结果表明:Ni-32%Cu合金在350℃保温时发生了调幅分解,且随着保温时间的延长,合金的调幅分解程度增大。随着调幅分解程度的增加,Ni-32%Cu合金形变织构中S取向和C取向份额呈下降趋势,B取向份额呈上升趋势。这主要是因为调幅组织在形变时,只有少数的滑移系开动,促进了平面滑移,抑制了交滑移的进行;随着调幅分解程度的增加,调幅相所占比例增加,调幅相的存在对位错有钉扎作用,使得位错的可动性下降。

A Ni-32%Cu alloy ingot was prepared by plasma arc melting and vacuum induction re-melting,and the experimental alloy was obtained by hot forging,hot rolling and annealing.Three kinds of Ni-32%Cu alloys with different spinodal decomposition degrees were obtained by holding at 350℃for 0 h,1.5 h and 4.0 h.The influence of spinodal decomposition degrees on the deformation texture of the Ni-32%Cu alloy after cold rolling with 98%deformation was studied by X-ray four-ring diffractometer.The results show that the spinodal decomposition of the Ni-32%Cu alloy occurs after holding at 350℃for different time,and the spinodal decomposition degree of the alloy increases with the increase of holding time.With the spinodal decomposition degree increases,the S and C texture components in the deformation texture of the Ni-32%Cu alloy sheets decrease,and the B texture component increases.This is mainly because only a few slip systems are activated during the deformation of spinodal structure,which promotes the planar slip and inhibits the cross-slip.With the increase of spinodal decomposition degrees,the proportion of spinodal phase increases,and the existence of spinodal phase has a pinning effect on the dislocation,which makes the dislocation mobility decrease.