SiC在高强度灰铸铁中的应用

Application of SiC to High-Strength Gray irons

介绍了SiC在高强度灰铸铁中的应用情况。在感应电炉熔化HT250时,加入一定量的SiC,浇注6缸发动机缸体,研究SiC对铁液质量、铸件金相组织、力学性能以及炉衬寿命等的影响。结果显示:(1)SiC改善了铁液冶金质量,提高了铁液纯净度,改善了石墨形态,钝化石墨片尖角,减小铸件本体抗拉强度及硬度差异性;(2)由于SiC具有强还原性,减轻了锈蚀炉料对炉衬的侵蚀,延长了炉衬寿命;(3)使用SiC部分取代传统的75SiFe和增碳剂,可以降低铸件原材料成本。

The research on application of SiC to high strength gray irons was introduced. By melting high strength gray irons in induction furnace and by adding certain amount of SiC,the influences of SiC on iron melt quality,microstrneture and mechanical properties of the castings,and,as well as the working life of the furnace lining were investigated. The results showed： （1）SiC improved graphite morphology,blunted the sharp peaks of graphite flakes,reduced the strength and hardness differences of the casting body.（2）Since SiC has strong deoxidizing effect,the furnace lining erosion caused due to the eroded melting charge was reduced that lengthened the working life of furnace lining.（3）After using SiC to substitute partly 75SiFe and reearburizer, the cost of raw melting materials of castings was decreased.