The technique which can measure the transient welding deformation directly is very important to investigate the mechanism of welding deformation. In this study, in-situ displacement measurement method using digital camera is self-developed. This system is non-contact type and it doesn't need any complicated optical systems but it can measure the in-situ displacement over the full-field in high accuracy by using digital image correlation technique. Therefore, it is considered to be useful and easy to apply to practical problems. The number of measuring points that can be obtained at a time is more than 10 million. It is the same as the available pixels of the digital camera. Furthermore, since the active light source is not necessary in this system, the influence of the fluctuation of the atmosphere caused by the high temperature area is small.
In this study, the detail of the proposed system is performed and it is applied to the transient in-plane deformation problem under very high brightness lightened by welding arc. Through the comparison between the experiment and Thermal-elastic-plastic FE analysis, the validity of the transient transverse shrinkage distribution which is measured by proposed system is verified. The residual deformation is also investigated to check the accuracy and usefulness of the proposed system.
