Simulation of Residual Stresses after Straightening of Induction Hardened Components
Simulation of Residual Stresses after Straightening of Induction Hardened Components
复制标题
感应淬火零件矫直后残余应力的模拟
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
H. Kristoffersen
中科院分区：
文献类型：
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作者：
S. Haglund;H. Kristoffersen
摘要校直是一种制造过程，其中部件被弯曲并塑性变形，以达到所需的直线度。这是一个不必要的过程，但在许多情况下是必要的。例如，诸如渗碳和感应淬火之类的热处理操作可能产生需要矫直操作的程度的变形。除了额外的加工步骤之外，矫直的主要缺点是它改变了残余应力，从而降低了部件的疲劳强度。采用有限元法对表面淬火轴的矫直过程进行了数值模拟。本文带来了新的洞察的复杂性，在残余应力的变化，远远偏离简化的意见，在文献中提出的。它将表明，有一个通过硬化轴和表面硬化的一个之间的根本区别，以及浅和深表面硬化深度的轴之间。所研究的材料为42CrMo4，经一次喷丸感应淬火。结果表明，残余应力的变化是相当复杂的，在周围的一些位置，而其他位置有增加的应力与减少的压缩残余应力。残余应力的变化量在很大程度上取决于所需的弯曲，但通过以最佳方式进行矫直操作，可以减少负面影响。
Abstract Straightening is a manufacturing process where a component is bent, and plastically deformed, in order to reach a desired straightness. It is an unwanted but in many cases necessary process. For instance heat treatment operations such as carburizing and induction hardening may give distortions of magnitude that a straightening operation is required. The main disadvantage with straightening, apart from the extra processing step, is that it alters the residual stresses which decrease the fatigue strength of the component. In this paper, the straightening of a surface hardened shaft is simulated by FEM. The paper brings new insight into the complexity in the changes in residual stress that deviates far from the simplified views presented in literature. It will be shown that there are fundamental differences between a through hardened shaft and a surface hardened one as well as between shafts with shallow and deep surface hardening depths. The material studied is 42CrMo4 induction hardened by single shot. It is shown that the change in residual stresses is rather complex with decreased compressive residual stresses in a number of locations around the circumference while other locations have increased stresses. The amount of change in the residual stresses are largely governed by the required bending but by doing the straightening operation in an optimal way the negative effect can be reduced.