基于数字图像相关方法的焊接接头局部力学性能研究进展

The Development of the Investigation on the Local Mechanical Properties of the Weld Joint by Digital Image Correlation Method

锅炉、压力容器、管道等承压设备的制造均涉及到大量的焊接工艺。随着诸如应变强化等新型制造工艺以及设备向超高温服役环境的发展趋势变化,许多焊接结构设计及评价也逐渐从强度控制方法转向变形控制方法。因此,针对焊接接头局部力学性能,尤其是焊缝及热影响区不同区域力学性能的表征方法的研究显得日趋重要。本论文总结了现有的及近年来发展出来的热模拟、压痕、微试样和非接触测量等局部力学性能分析方法,并重点介绍了基于数字图像的非接触全场应变测量方法在局部力学性能测量上的应用研究现状,以及未来的发展方向。

Welding is the basic process method for the pressure equipment such as boiler, pressure vessel, pipe et al. With the application of the equipment at ultra-high temperature and the adoption of strain-hardening technology during the manufacture, the allowable stress of the materials cannot be determined simply by the strength parameters any more but the deformation parameters have to be taken into consideration. In order to estimate the deformation feature of the weld joint, the understanding of the local mechanical properties especially the properties distribution of the weld nugget and the heat affected zone becomes important. In this paper, the commonly used methods for investigating the local mechanical properties, including the thermal simulation, indentation, micro specimens test and non-destructive test, are briefly introduced at first. And then, an image based non-destruction full field strain test method called digital image correlation and the development of its application on the studies of the local mechanical properties of the weld joint in the world are emphatically presented.