Short-time heat treatment of press hardened steel for laser assisted clinching
Short-time heat treatment of press hardened steel for laser assisted clinching
复制标题
DOI：
10.1179/1743284714y.0000000556
复制
发表时间：
2014-07
影响因子：
1.8
通讯作者：
M. Reich;J. Osten;B. Milkereit;J. Kalich;U. Füssel;O. Kessler
中科院分区：
文献类型：
--
作者：
M. Reich;J. Osten;B. Milkereit;J. Kalich;U. Füssel;O. Kessler
高强度钢的铆接由于其相对低的延展性而目前是困难的。因此，开发了一种新的方法来铆接这些钢种。这可以通过在铆接过程中用激光在接头处局部加热片材来实现。本文采用热分析和量热实验研究了22 MnB 5钢的短时回火行为。回火过程的不同阶段已经根据高达1000 K s-1的加热速率确定。特征回火反应转移到更高的温度，增加加热速率。在此基础上，选择了合适的短时热处理工艺参数，并将其应用于铆接过程。从而首次成功地利用激光辅助对压制硬化钢22 MnB 5进行了铆接。通过金相分析和硬度测试对激光辅助铆接接头进行了表征。可以看出，在铆接接头中，由于引入的激光热，仅发生轻微的强度损失。
Clinching of high strength steels is currently difficult due to their relative low ductility. Hence a new method has been developed to clinch these steel grades. This could be achieved by heating the sheets locally at the joint by a laser during the clinching process. The short-time tempering behaviour of the press hardened steel 22MnB5 has been investigated by dilatometry respectively calorimetry experiments. Different stages of the tempering process have been identified depending on heating rates up to 1000 K s−1. Characteristic tempering reactions were shifted to higher temperatures with increasing heating rate. Based on these results, suitable short-time heat treatment parameters have been selected and transferred to the clinching process. Thereby the press hardened steel 22MnB5 has been successfully clinched with laser assistance for the very first time. The laser assisted clinched joint has been characterised by metallographic analysis and hardness testing. It could be shown, that in the clinching joint only a slight strength loss occurs due to the introduced laser heat.