变形温度及变形量对挤压态FGH96合金晶粒异常长大的影响

基于楔形试样等温锻造试验,采用Deform-3D模拟软件,模拟确定了楔形试样中不同位置的变形量,研究了不同变形温度和不同变形量对挤压态FGH96合金晶粒异常长大的影响。结果表明：在压下速率0.04 mm/s的平模镦粗试验条件下,挤压态 FGH96合金出晶粒异常长大的临界变形温度为1100℃,临界变形量为2%；1000~1070℃锻造变形时,合金不易发生晶粒异常长大,但也有“临界变形量”特征,变形量5%~10%区域晶粒平均直径最大；选择15%及以上的变形量,可以避免晶粒异常长大,并获得均匀细小的晶粒组织。

Effect of Deforming Temperature and Strain on Abnormal Grain Growth of Extruded FGH96 Superalloy

Based on the experiments of isothermal forging wedge-shaped samples, Deform-3D numerical simulation software was used to confirm the strain distribution in the wedge-shaped samples. The effect of deforming temperature and strain on abnormal grain growth (AGG) in extruded FGH96 superalloy was examined. It is found that when the forging speed is 0. 04 mm/s,the critical AGG occurring temperature is 1100 ℃,and the critical strain is 2%. AGG does not occur within 1000-1070 ℃,but still shows the feature of‘critical strain’ ,and the region with strain of 5%-10% has the largest average grain size. AGG can be avoided and the uniform fine grains can be gained when the strain is not less than 15%.