Research On Thermal-mechanical Coupled Wear Behavior Of PVD Cladding Layer For Hot-work Die Steel

In recent years,hot forming has became one of the most popular manufacturing process for automotive panels with the continuous advancement and development of science and technology,and hot forming tools are the core components in the hot forming process.In the abominable and high temperature work condition,the thermal-mechanical coupled wear behavior of hot forming tool is easily occurred in the cycle of stamping deformation process.The excessive wear would directly induce to the surface failure of the stamping die,which greatly increases the manufacturing cost of automotive hot forming panles.Currently,PVD coating is often used to improve the wear resistance of hot forming mold in industrial production.It is of great significance and value to in-depth study the thermal-mechanical wear behavior of hot forming mold materials with the PVD coating in the forming process under complex high temperatures,and futher evaluate the wear resisting property of the corresponding materials.In this paper,series of scientific experiments and simulation analysis were conducted to evaluate two kinds of hot forming tool steel materials(H13 steel,DTDVA steel)with PVD coating layer,and also compared with non-coating of the sample to systematically analyze the thermal-mechanical wear mechanism of typical steels with PVD coating material.In addition,the thermal-mechanical wear behavior of hot forming mold material owning the typical strike-slip-holding process was further simulated by the actual industrial production process of hot forming.The detailed research contents are as follows:Accuracy in order to improve the result of the experiment,the experimental sample surface morphology of thermal-mechanical couped wear specimens was observated by using the scanning electron microscopy(SEM)and the high power metallographic microscope in this paper.The shock,slip,the holding three process area of the surface morphology were mainly observed to explore the wear conditons of the specimen surface with and without of PVD coating layers after the impact,and futher the contrast analysis of the degree of wear on the repecitive surfaces.Furthermore,the wear condition of hot forming die materials after high-cycle impact was investigated by using Abaqus software and combing with the Archard wear theory.The FE simulation model of actual impact-sliding-holding process was established.The fitting relationships between wear depth and impact times were obtained under the influence of pre-set temperatures and PVD coating conditions.Moreover,the experimental data of wear depth on the actual experimental sample surfaces were not only compared and analyzed,but also the accuracy was verified.The above research content has a certain reference significance and value to select of hot forming mold materials and evaluate of the service life of corresponding materials in the actual production process.