论文部分内容阅读
我国一家矿山运输设备修理厂将下述成分(％)的球铁进行等温淬火:C3.0～3.2,Si2.5～2.8,Mn0.6,P0.06～0.07,S<0.03,RE0.04～0.05,Mg0.05～0.06,加热温度900℃,在硝盐浴炉(400℃)中淬火进行等温处理,得到的铸件,强韧性很好(a_k=9～10kgf·m/cm~2),用这种铸件可代替锻件使用,例如汽车换挡拨叉就是其中之一,进口拨叉虽为锻件a_k值仅为6～8kgf·m/cm~2,国产的更低只有3～4kgf·m/cm~2,不仅质量低,自由锻件比经等温淬火的球铁件要贵70％以上。一些细薄件例如电力机车上滑板导框、弹簧鞍和衬垫等使用等温淬火球
China’s mine transportation equipment repair shop isothermal quenching the following components (%) of the ductile iron: C3.0 ~ 3.2, Si2.5 ~ 2.8, Mn0.6, P0.06 ~ 0.07, S <0.03, RE0.04 ~ 0.05, Mg 0.05 ~ 0.06, the heating temperature 900 ℃, quenching in the salt bath furnace (400 ℃) isothermal treatment, the resulting castings, good toughness (a_k = 9 ~ 10kgf · m / cm ~ 2) , With this casting can be used instead of forgings, such as car shift fork is one of them, although the forging fork forging a_k value of only 6 ~ 8kgf · m / cm ~ 2, made only 3 ~ 4kgf · lower m / cm ~ 2, not only the quality is low, the free forging is more expensive than isothermal quenched ductile iron parts by more than 70%. Some thin pieces such as electric locomotive skateboard guide frame, spring saddles and pads using isothermal quenching ball