研究了高速货车侧架的裂纹形成机理,分析了裂纹产生的原因。通过在铸件的热节和转角部位放置冷铁,控制硫、磷的含量在0.015%以下,碳含量控制在中、下限,增大造型材料退让性,浇注温度控制在1 560~1 570℃,优化热处理工艺,减少砂缝等工艺措施,有效控制了侧架铸件的裂纹缺陷。经批量生产验证,裂纹得以消除,取得满意效果。 Crack formation mechanism of high-speed truck side frame was studied and the reason of crack was analyzed. Through the placement of chilled iron in the hot section and the corner of the castings, the content of sulfur and phosphorus is controlled below 0.015%, the carbon content is controlled at the middle and the lower limits, the concretion of the molding material is increased, the pouring temperature is controlled at 1560-1 570 ° C, Optimize the heat treatment process, reduce the sand seams and other process measures, effectively control the side frame castings crack defects. After mass production verification, cracks can be eliminated and satisfactory results achieved.