Deformation analysis of hot stamping tools by thermal-fluid-mechanical coupled approach based on MpCCI.

Hot stamping tools with cooling systems are key facilities for hot stamping processes in the automotive industry. In hot stamping, the tools are heated by workpieces and rapidly cooled by cooling water. The thermal deformation of the tools has a significant influence on the properties of the hot stamped parts and the useful life of the tools. In this paper, a multi-field simulation method is proposed for analysis of deformation in the tools. Based on a mesh based parallel code coupling interface, a thermal-fluid-mechanical coupled model is established to analyse the cooling effect and the deformation of the tools. The experimental set-up was built to verify the multi-field coupling model. It is shown that the cooling rate of the hot stamped part was 217°C s−1, higher than the critical cooling rate of 30°C s−1. The temperature history of the hot formed part was in good agreement with the experimental result. The cooling ducts were deformed because of the thermal expansion of the hot tools. This led to stress concentration at the rectangular corner of the ducts. The speed of cooling water flow increased by 112% through the bottom ducts, while at the corners of the ducts, the speed was very low and a 'hot spot' appeared. [ABSTRACT FROM AUTHOR]