Basic Experimental Research On Hot Stamping Process Parameters And Die Of Ultrahigh-strength Steel

Whether the world or China，the automobile industry has entered the stage of rapiddevelopment，China has become the second of automobile country in the world，whetherthe safety requirements of automobile or the demand of energy saving，more and morevoice of the light weight becomes more and more urgent，it led to the leap development ofhot stamping，this paper takes ultra high strength steel BR1500HS of baosteel as anexample，through the research of hot stamping process and theory firstly，and the basicresearch is taken on the plate，then the reasonable process and mold parameters aresummarized by specific process experiment and research of die，this paper gives somesupplement to the conclusion got before with abaqus because of the limitation ofexperiment.This paper takes BR1500HS as the main line，the empirical calculation formula of Msis got by the equation of linear regression，and Ms of BR1500HS is399°C，the basicresearch is taken on the plate，wind cooling is not suitable for hot stamping is verified byexperiment，the descent speed of temperature is20°C/s in7s by analyzing the change ofthe plate’s water quench and temperature on different moving time，BR1500HS whichmoved within8s is determined by improving the transformation of martensite and theforming ability.The flat die is developed indepently to study the cooling and heat transfer，theproposal of bearing pin can prevent direct contact between sheet metal and die，the spinlock module is used to provide the packing pressure，the processing difficulties andfunction have been analyzed，and through the stress concentration analysis of flat die withansys，some suggestions of processing on die hole have been given，to study theexperimental of quenching by setting various adjustable parameters of mold in differentconditions，analysis of the effect of quenching properties of various paramerers onBR1500HS，the heating temperature is850°C~900°C，incubation time is about5min。moving time is4s~8s，which is determined as the best technology parameter of BR1500HSby orthogonal experiment，added some simulation，it explains mold size does not affect thebasic material properties of plate quenching，initial temperature of die has great effects onquenching performance，it means that practical hot stamping production should useuninterruptible water in order to ensure the stability of the initial temperature of mold and good quenching effect.The research of hot stamping mould is conducted in the light of trough parts，thespring mounted on guide pin and locking device etc. are presented that this kind of moldcan be applied to the common press，it gives the reference opinions of the mold materialselection、cooling pipe etc. These conclusions provide important reference materials for thedesign of hot stamping and the establishment of hot stamping process for BR1500HS.