Papers by Keyword: Residual Stress Simulation

Abstract: Welding parameters have important affect on welding quality. In this paper, temperature field and residual stress field simulation of thin 316L stainless steel plate are performed by finite element method. The welding process is multi-pass butt TIG(Tungsten Inert Gas) welding. Simulation model are established by SYSWELD code with multi-pass bead. A Gaussian heat source representing the arc energy is verified and the temperature distribution in multilayer welding process is simulated. Then the results are compared with test results measured by thermal-couples. Effects of welding speed and interpass cooling time during multi-pass on temperature field and stress field are studied. The results show that the faster the welding speed and the longer the cooling time, the higher the residual stress will be.

Abstract: To enhance the fatigue resistance of mechanical components, different surface treatment processes are often applied to put the near surface layer into compression. Surface treatment processes are typically associated with deformation and work-hardening of the material. When applying x-ray diffraction techniques to the characterization of such surfaces, the work-hardening will cause the x-ray diffraction peak width to increase. When peak widths reach high values, the peak tail may extend beyond the active area or window of the multichannel x-ray detector, in which case the peak is truncated. Subsequent analytical treatment of broad diffraction peaks is troublesome and advanced numerical methods are required to accurately determine the peak position. The following work indicates that when a wider detector is used it is possible to collect the full, non-truncated peak, determine the peak position with a high level of confidence and subsequently, to calculate the residual stress with much improved repeatability and reproducibility.