Effect Of Casting Process On Microstructure And Properties Of Wear Resistant High Manganese Steel Hammer

In this research project,high-manganese steels were prepared by sand casting process,ironcoated sand casting process and metal casting process.The influence of three casting processes on the microstructure,mechanical properties and anti-wear performance of high manganese steel was studied.The results of the study indicated that the number of non-metallic inclusions in the sand casting process was highest in high-manganese steels in the as-cast state,and they were in a massive and linear distribution;the number of non-metallic inclusions in the iron-mold sandcoating casting process was small and they were in a massive distribution.The number of nonmetallic inclusions in the metal casting process was the smallest,and it was distributed in spots.After heat treatment,the grain size ratings of the high-manganese steels in the sand casting process,the sand casting process and the metal casting process were 3.0,3.5 and 4.0 respectively.With the acceleration of the cooling rate,the grains of high-manganese steel had become more and more refined,and the tensile properties,impact toughness and wear resistance of high-manganese steel have been greatly improved.The metal mold casting process has the best tensile properties and impact toughness,followed by the iron mold sand casting process,and the sand casting process the worst.In the impact abrasive wear test with impact energy of 2 J,the heat loss of the high manganese steel in the metal mold casting process was the lowest,followed by the iron mold sand casting process,and the sand casting process was the most.The loss of weight of the high-manganese steel mill of the metal mold casting process was reduced by about 30.9% compared with the iron mold sand casting process,and the weight loss of the iron mold sand casting process was reduced by about 31.5% compared to the sand mold casting process.The degree of wear and work hardening varies greatly.The metal mold casting process was the highest,the iron mold sand casting process was followed,and the sand casting process was the lowest.The hardness of the high-manganese steel of the metal mold casting process was about 31.9% higher than that of the iron mold sandcoating casting process.The hardness value of the high manganese steel of the iron mold sand casting process was higher than that of the sand mold.Increased by approximately 13.3%.In the impact abrasive wear tests with an impact energy of 4.5 J,the heat loss of the highmanganese steel in the heat treatment state of the metal mold casting process was the lowest,followed by the iron mold sand casting process,and the sand casting process was the most.The loss weight of the metal mold casting process was reduced by about 32.5% compared to the iron mold sand casting process,and that of the iron mold sand casting process was reduced by about 20.8% compared to the sand casting process.The difference in wear and work hardening was still greater.The high manganese steel in the metal mold casting process was the highest,followed by the iron mold sand casting process,and the sand casting process was the lowest.The hardness value of the high manganese steel of the metal mold casting process was about 8.5% higher than that of the iron mold sand casting process;the hardness value of the iron mold sand casting process after being hardened was about 13.6 % higher than that of the sand mold casting.When the impact energy was 4.5J,the high manganese steel has higher wear resistance and work hardening performance than the impact energy of 2J.The three casting processes promote different solidification speeds and different grain sizes of high-manganese steels,which were the main reasons for the differences in microstructure,mechanical properties and wear resistance of high-manganese steels.The chilling effect of the metal mold casting process was the strongest.The metal mold casting process promotes the highest solidification rate of the high manganese steel and the finest grains.Therefore,the mechanical properties and wear resistance of the high manganese steel were the highest under this process.