Design And Technology Research Of Hot Trimming Die Of High Strength Steel For Hot Forming Parts

Hot stamping of high-performance of boron steel, which achieves the reduction of vehicle weight and fuel consumption, while meets the crash safety requirements at the same time. This has become a hot technology in automobile manufacturing. However, there are still difficulties for the most automotive manufacturers in cutting hot stamping technology, there are such problems as large cutting fore, sever wear and sometimes unexpected tool failure. And laser cutting technology is generally employed by manufacturer, in spite of its long cycle time, high production cost, and even poor product quality.Hot trimming technology of high-strength steel is made the sheet can be trimmed or punched with high ductility and low hardness, which can improve product quality, shorten cycle time and reduce the production cost.According to the characteristics of high strength steel hot forming material, the hot stamping and punching die was designed according to the standard of conventional mold design,Several basic principles of hot stamping die design are put forward; influence of trimming temperature, clearance on cutting force, sheared surface quality were researched; the process optimization of trimming die were designed. The main conclusions are as follows: Trimming force decrease with the trimming temperature, clearance increase. The higher temperature, smaller clearance assures smoother sheared surface. Among these parameters, the influence of die clearance is greater. Based on the above laws, optimal processing parameters with trimming temperature above 700 ℃, clearance about 10% for cutting and 7% for punching of the sheet are determined for 1500 high strength steel.