柱状晶方向对离心铸造HK40炉管蠕变裂纹扩展行为的影响  

DEPENDENCE OF CREEP CRACK GROWTH ON COLUMNAR GRAIN ORIENTATION IN CAST HK40 TUBE

作　　者：祝苏明[1] 张俊善[1] 王来[1] 王富岗[1] 

机构地区：[1]大连理工大学

出　　处：《钢铁》1994年第7期50-54,共5页Iron and Steel

摘　　要：从离心铸造ＨＫ４０炉营上截取柱状晶方向与预制裂纹方向（炉管径向）呈不同角度（θ）的紧凑拉伸型试样，在８７１℃进行了恒载荷蠕变裂纹扩展试验。发现裂纹沿柱状晶方向扩展，而随θ角的增加，裂纹扩展抗力增大。θ角与裂纹扩展速率之间存在下列依赖性：ｄａ／ｄｔ＝Ａ［Ｋｃｏｓ￣２（θ／２））￣ｍ。裂纹扩展速率与能量率积分（Ｃ）的良好关联表明，Ｃ是铸态ＨＫ４０合金的蠕变裂纹扩展的控制参数。Abstractcompact tension specimens with columnar grain oricntation inclined to crack plane at an al1gle(θ)in the range of 0℃～60℃ were cut from a cast HK40 tube.Constant load creep crack growth tests were performed at 871℃,It is shown that cracks propagate along colunmar grain orientation and the creep crack growth resistance increases with increasing of θ.The depen-dence of creep crack growth rate on the columnar grain orientation can be expressed aSThe good correlation between crack growth rate and energy rate integral(C)indicates that C is the controlling parameter for creep crack growth of cast HK40 tube.

关 键 词：HK40合金 炉管 离心铸造 裂纹扩展 

分 类 号：TG249.4[金属学及工艺—铸造]