两种生铁对可淬硬凸轮轴金相组织和硬度的影响

Effect of Two Pig Irons on the Metallurgical Structure and Hardness of the Hardened Camshaft

研究了四川钒钛生铁和河北球墨生铁对491Q可淬硬凸轮轴金相组织和硬度的影响。研究表明:四川钒钛生铁的金相组织由细小点状石墨+A型石墨+碳化物+珠光体组成;河北球墨生铁的金相组织由A型石墨+C型石墨+珠光体组成。由Ⅰ组配料(230kg四川钒钛生铁+100kg废钢+220kg回炉料+其它合金)铸造的凸轮轴的金相组织为4-6级A石墨+少量E型石墨+95%珠光体+5%渗碳体,基体硬度为252～255HB;由Ⅱ组配料(150kg河北球墨生铁+80kg四川钒钛生铁+100kg废钢+220kg回炉料+其它合金)铸造的凸轮轴的金相组织为4-6级A型+少量E型石墨+100%珠光体,基体硬度为210～229HB。作者初步分析了产生上述现象的原因。

Sichuan V-Ti pig iron and Hebei ductile iron have been used to manufacture 491Q type hardened camshaft and the effect of both iron on the microstructure and hardness of the camshaft been researched. Studies have shown that the microstructure of Sichuan vanadium-titanium pig iron consists of as tiny dot graphite＋A type graphite＋carbide＋ pearlite while the microstructure of Hebei ductile iron consists of A-type graphite＋C-type graphite＋pearlite.The microstructure in the camshaft manufactured from the group- I ingredient （230 kg Sichuan V-Ti pig iron＋100 kg scrap steel＋220kg back charge＋other alloys） consists of the 4-6 grade A-type graphite ＋small amount E-type graphite ＋95% pearlite＋about 5% cementite, and his matrix hardness is 252-255HB.The mjcrostructure in the camshaft manufactured from the group- II ingredient （ 150 kg Sichuan V-Ti pig iron＋80 kg Hebei ductile iron＋100 kg scrap steel＋220 kg back charge＋other alloys） consists of the 4-6 grade A-type graphite ＋small amount E-type graphite ＋100% pearlite,and its matrix hardness 210-229HB.The above-mentioned phenomenon has been given preliminary analysis.