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楔横轧空心轴类件存在壁厚分布不均问题,特别是在小直径大长径比空心件楔横轧成形中更为突出.本文在Gleeble-1500D热模拟实验机上进行了5Cr21Mn9Ni4N耐热钢的热压缩实验,得到了5Cr21Mn9Ni4N的热变形本构方程.通过改变芯棒直径,采用有限元仿真和实验相结合的方法,研究了楔横轧轧制空心气门过程中的壁厚变化规律.研究结果表明,带芯棒轧制时,芯棒直径存在临界值,在该值下进行轧制,空心气门预制坯壁厚均匀性最优;楔横轧空心件时,金属轴向均匀流动是壁厚均匀的必要条件;轧件轴向拉应变减小,径向压应变变大,周向应变在0附近且为拉应变时,壁厚较为均匀.
The wedge cross-rolling hollow shaft parts have the problem of uneven distribution of wall thickness, especially in the small-diameter large aspect ratio hollow wedge cross-rolling forming.In this paper, 5Cr21Mn9Ni4N heat-resistant steel , The thermal deformation constitutive equation of 5Cr21Mn9Ni4N was obtained.With the change of mandrel diameter and the combination of finite element simulation and experiment, the variation of wall thickness in the process of cross-rolling hollow valve was studied. The results show that there is a critical value for the mandrel diameter when rolling with mandrel, and the thickness uniformity of hollow preform is the best when the mandrel is rolled under this value. Uniform thickness of the necessary conditions; rolling axial strain decreases, the radial compressive strain becomes larger, the circumferential strain near 0 and the tensile strain, the wall thickness is more uniform.