高强度高弹性模量低应力铸态球墨铸铁的研究  

Study on High Strength,High Elastic Modulus and Low Residual Stress of As-Cast Ductile Iron

作　　者：卫东海[1] 李克锐[1] 吴现龙[1] 李桐[1] 赵怀普[1] 

机构地区：[1]郑州机械研究所,河南郑州450001

出　　处：《铸造》2014年第2期120-127,共8页Foundry

基　　金：国家"高档数控机床与基础制造装备"科技重大专项资助项目(2012ZX04010031)

摘　　要：添加不同含量的合金元素Mn和Cu浇注球墨铸铁Y型试块和应力框铸件,通过拉伸试验和金相检验研究了Mn和Cu对铸态球墨铸铁组织和性能的影响,采用盲孔法测量铸件的残余应力。结果表明:球墨铸铁中单独加入锰元素难以同时达到高强度和高弹性模量;球铁中添加适量的Cu元素能显著促进珠光体生成并减小珠光体层片间距、提高其抗拉强度和弹性模量;1.0%Mn-0.5%Cu复合处理的球墨铸铁的基体组织完全珠光体化,抗拉强度和弹性模量分别达到740 MPa和182 GPa,其残余应力随碳当量的增加而降低,碳当量为4.6时最大残余压应力和拉应力分别为-76.9MPa和53.7 MPa,同时达到了高强度、高弹性模量、低应力的要求。Y blocks and stress-boxes were poured by adding different content of Mn and Cu alloy. Tensile test and metallurgical microscopy analysis were done, the effect of Mn and Cu on microstructure and properties of ductile iron was studied. The residual stress of stress-box castings was measured with blind hole method. According to the results, it is difficult to achieve high strength and high elastic modulus at the same time by adding Mn alone in ductile iron. Cu addition of proper quantities can improve pearlite and decrease pearlite lamellar distance significantly, meanwhile improve tensile strength and elastic modulus. The matrix of ductile iron with 1.0%Mn-0.5%Cu is completely pearlite. The tensile strength and elastic modulus respectively is 740 MPa and 182 GPa. The residual stress decreases with the increase of carbon equivalent. When carbon equivalent is 4.6, the maximum residual compressive stress and tensile stress respectively is -76.9 MPa and 53.7 MPa. The requirement of high strength, high elastic modulus and low residual stress is achieved at the same time.

关 键 词：锰 铜 铸态球墨铸铁 抗拉强度 弹性模量 碳当量 残余应力 

分 类 号：TG255[金属学及工艺—铸造]