Experimental Study On Surface Damage Of High-strength Steel Plate Stamping

Today,the use of high-strength steel plate is one of the important means to achieve automobile lightweight.However,compared with ordinary steel plate,the high-strength steel plate production forming process requires greater tensile force,and the friction between steel plate and mold increases,so that steel plate is prone to surface damage defects.At present,the U-shaped or box-shaped experimental devices used to study surface damage defects can simulate the occurrence of surface damage defects,but require a large number of steel plates,resulting in great waste of human and material resources.However,most research at home and abroad focuses on the mechanism of surface damage and the measures to prevent and improve the surface adhesion and napping of high-strength steel.Little research has been done into some specific influencing factors,especially the relationship between mold surface treatment condition and high-strength steel surface damage.Therefore,it is very important to invent a more convenient and scientific simulation experiment device of high strength steel surface damage,especially the influencing factors and rules of the surface damage of advanced high-strength steel.In this paper,a simple experimental device dedicated to overcoming the aforesaid shortcomings is designed,which can simulate the surface damage easily and quickly in high-strength steel sheet forming process..I use the simulation experimental device to conduct simulation experiment by changing the hardness of the mold head,changing the surface condition of the mold surface such as polished coating,and changing the pre-stretch rate of the high-strength steel sheet in order to study the origin of occurrence of surface defects such as adhesion and napping,and the influencing rules of various variables on the surface damage of high strength steel in the forming process of high-strength steel plate.The results show that increase of mold head hardness,polishing and Cr coating of mold head,and reduction of the transverse deformation of high-strength steel plate are beneficial to improve the friction state between mold and the high-strength steel plate.The results are of important guiding significance in the formulation of high-strength steel plate forming process.