| Since the 1980s,the development impetus of the mold industry is very rapid,followed by the requirements of the mold steel is also higher and higher.Under the booming development trend of the mold industry,the production technology is also advancing day by day.The working conditions of the mold steel are very bad,and the performance of the mold steel needs to be constantly optimized to keep pace with the rapid development of the mold industry.In order to solve this demand,the world’s major industrial countries are actively developing and developing better quality mold steel varieties.H13 mold steel as a widely used kind of hot mold steel,its excellent performance,has good thermal strength,high toughness and quenching and fatigue resistance,can act on extrusion mold,hot forging mold and die casting mold,has a very high representative.H13 die steel working environment is very bad,cold and cold,plastic deformation,wear,impact and thermal fatigue will give H13 die steel huge stress,if H13 die steel operation in the production process is not standard,will reduce the life of H13 die steel,sudden failure in the process of service,will not only can cause property losses,serious will also appear safety accidents.Based on this,this paper combines the H13 mold steel production process and the existing quality problems:First,through the homogenization annealing experiment of different parameters of H13 electric slag ingot,the influence of homogenization annealing temperature and time on the elimination degree of dendite segregation and impact toughness is studied.Based on the actual conditions,the most suitable homogenization process parameter is the annealing temperature of 1250℃insulation time of 12 hours.Secondly,the homogenization ingot is subjected to thermal compression experiment,the rheological curve under different thermal deformation conditions is analyzed,the influence law is summarized,the heat processing map of H13 die steel is drawn,and the best process parameters of H13 die steel are determined:the deformation temperature is 1050℃～1100℃,and the strain rate is selected between0.2～0.7s-1.In order to effectively analyze the influence of thermal deformation process of mold steel on tissue performance,based on the mechanical characteristics of forging process,establish the finite-element numerical simulation of multi-direction forging model,simulate the multi-direction forging process with different forging temperature and forging rate,and observe the size and distribution rules of metal damage,flow speed,stress and strain.Finally,the forged H13 die steel after homogenization treatment was fired,and then the spherical annealing experiment was carried out to study the influence law of different spherical annealing processes and temperature on the spherical organization of H13 die steel,and select the most suitable spherical annealing process parameters according to the actual situation. |
