楔横轧成形小断面收缩率轴类件热力耦合数值模拟  

Thermo-mechanical coupled numerical simulation of forming light area reduction shafts by cross wedge rolling

作　　者：刘文科[1] 张康生[1] 孟令博[1] 胡正寰[1] 

机构地区：[1]北京科技大学机械工程学院,北京100083

出　　处：《中南大学学报（自然科学版）》2012年第1期118-123,共6页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51075030)

摘　　要：借助DEFORM-3D有限元软件针对小断面收缩率轴类件的楔横轧成形过程进行热力耦合数值模拟,分析轧件在成形过程中的温度变化规律;通过与常规断面收缩率轧件进行对比,得到小断面收缩率轧件的各向应力分布状态。模拟结果表明:小断面收缩率轧件与轧辊接触表面的温度变化较为剧烈,而轧件内部中心位置附近温度无显著变化;由于轧制位置的不同,轧件各横截面间的温度变化有所差异,曲线的波动存在着相位差。此外,小断面收缩率轧件在接触变形区周围的横向和径向压应力较大而轴向压应力较小,导致其横截面容易出现椭圆化;其中心附近区域由于受到比常规断面收缩率轧件更大横向和轴向拉应力影响,因而更易产生疏松、裂缝等缺陷。进行轧制试验,验证了模拟结果的可靠性。The forming process of the light area reduction shaft by cross wedge rolling was simulated by means of DEFORM-3D software.The temperature variation of the rolled piece in the forming process was presented.And the stress distributions of the cross section for the light area reduction rolled piece were analyzed through comparisons with the conventional area reduction rolled piece.The results indicate that there are dramatic temperature changes in the contact area between the rolled piece and the roll,while no significant changes occur near the center of the rolled piece.Due to the different rolling positions,the temperature variation curves between all cross sections are distinct and phase difference exists between fluctuations in the curves.Around the contact deforming zone,there are larger lateral and radial but smaller axial compressive stress than the conventional area reduction rolled piece,causing elliptical deformation of the cross section for the light area reduction rolled piece to appear.And near the center of rolled pieces,larger lateral and axial tensile stresses lead to the generation of central defects such as porosities and cracks.Rolling experiments are carried out to verify the reliability of the simulation results.

关 键 词：小断面收缩率 楔横轧 有限元法 热力耦合 温度 

分 类 号：TG335.19[金属学及工艺—金属压力加工]