Research On Die-casting Mold’s Thermal Fatigue Crack Initiation And Extension Laser Blocking Technology

Due to suffering the conditions of alternating hot and cold or under complexstress environment, die casting mold damaged, how to improve the service life ofthe die casting mold, has been an exploring topic. In recent years, more and moreresearchers are paying attention to the mold’s laser blocking technology. Moldlaser blocking technology improved the organizational structure of the surfaceand improved its wear resistance, enhanced fatigue resistance, which caneffectively prolong the service life of the mold, which greatly reduced the cost,improved economic benefits.From the perspective of theory, this paper studies on and several kinds ofanti-fatigue and anti-wear mechanism of organisms, combining with the diecasting mold’s material and the process characteristics, as well as the domesticapplication level of laser processing technology, has developed a laser blockingmodel process intensification.In the research process of concrete, on one hand, based H13is a kind of diecasting mold steel, which suffered periodic heating and cooling, so it emergesthermal fatigue very easily. To solve this problem of studying the process of diecasting mold steel’s thermal fatigue, through the method of comparing thethermal fatigue test with ANSYS thermal fatigue simulation method to predictthe thermal fatigue cracks of the die casting mold. By using the HMTH1thermocouple heating self-constraint thermal fatigue testing machine, heating andcooling the part of specimen in periodicity, then observe and record the cycletimes and crack lengths when occur thermal fatigue cracks, and using ANSYSsoftware to complete finite element simulation of the experiment, then get theresult of heating stress fields, temperature fields and cycle crack paths of thedifferent thermal fatigue cycles, simulating the extended paths and thetemperature fields、thermal stress fields in a thermal fatigue cycles, by contrast the results of the experiment with finite element numerical simulation, in order tosolve the problems of die casting steel thermal fatigue crack initiation andpropagation better, on the other hand, through the DPS software designorthogonal experiment, after the range analysis, then the laser parameters wereoptimized, at the same time, the different morphological structure was studied bythermal fatigue test, and applied in die casting mold at actual work, then tracingthe experiment, and the experimental results found that: laser blocking methodcan effectively improve the thermal fatigue resistance of working surface of diecasting mold steel, thereby prolonging the service life of the die casting mold.