热压缩形变不均匀性的影响因素及取样方法的研究

 采用有限元方法对热压缩物理模拟过程进行了模拟，分析了接触静摩擦系数、形变量、应变速率对热压缩方向应变及应变速率均匀性的影响，对不同取样位置及分析方向的形变均匀性进行了分析，并观察相对应的原奥氏体晶粒，进行验证。结果表明，试样热压缩方向的应变及应变速率由心部向端部逐步减小，距试样中心1/4位置处最接近设定的应变及应变速率；接触静摩擦系数对试样热压缩方向形变不均匀性影响显著，形变量、应变速率对形变不均匀性的影响较小；推荐自热压方向1/4位置处取样，该处应变及应变速率基本符合设定条件，且形变均匀性最好。

Investigation on Influencing Factors of Deformation Non-Uniformity and Method of Sampling

The physical simulation of hot compression was carried out by finite element method(FEM).The effect of contact static friction factor,strain and strain rate on the strain and strain rate non-uniformity of compressed direction was analyzed.And the deformation uniformity at different sections and directions was demonstrated by the prior austenite grain.The results show that the strain and strain rate are decreased from the center to the ends,and the 1/4 position of those are most approximate to the strain and strain rate set.The contact static friction factor plays an important role on the deformation non-uniformity,while the strain and strain rate make little impact on that.The 1/4 position along the compressed direction is the best way to sample,where is deforming uniform.