RECaBa孕育剂和Mo、Cu、Cr对高强度灰铸铁组织和性能的影响

Influence of RECaBa Inoculant and Mo,Cu,Cr on Structure and Properties of High Strength Gray Irons

采用工频感应电炉熔炼和呋喃树脂自硬砂造型,研究了不同加入量的RECaBa孕育剂和Mo、Cu、Cr对高强度灰铸铁金相组织和力学性能的影响。结果表明,RECaBa孕育剂可细化石墨且钝化尖角,细化珠光体,使共晶团数量增多;在不加入Mo的情况下,当原铁液的w（S）量范围为0.02%-0.03%时,RECaBa孕育剂加入量为0.5%-0.6%时,铸件本体抗拉强度可达300 MPa以上;Mo对提高铸件本体的抗拉强度有显著影响,w（Mo）加入量为0.4%-0.6%时,铸件本体的抗拉强度稳定保持在310 MPa以上;按照试验所采用的加入量,3种合金元素中Mo对改善灰铸铁金相组织、提高力学性能的效果最明显,Cu次之,Cr的影响不明显。

The infl uenee of different addition amounts of RECaBa inoculant and Mo, Cu, Cr on the mierostrneture and mechanical properties was investigated by adopting main frequency induction furnace for iron melting and furan resin sand for making mould. The results showed that RECaBa inoculant could reduce graphite size and truncate the sharp edge of graphite flakes, refine the pearlite and increase eutectic cell count. When no Mo was added, and the S content of base iron was 0.02% -0.03%, the proper addition amount of RECaBa inoculant was 0.5%-0.6% that resulted in the tensile strength of casting it-self higher than 300 MPa. Mo could increase the tyensile strength of the casting it-self obviously, and when adding 0.4%-0. 6% Mo, the tensile strength of casting it-self was kept stably higher than 310 MPa. Base on the addition amounts adopted in the test, Mo had the most obvious effect of improving mechanical properties, Cu had less effect, and the effect of Cr was not obvious.