Study Of Low-carbon Ductile Iron Wear And Corrosion Resistance

In this dissertation, the author has studied on the wear mechanism and property of Low-carbon Ductile Iron with the six chemical compositions of 1.2%C, 1.8Si; 1.2%C, 2.0%Si; 1.4%C, 2.0%Si, 1.4%C, 2.0%Si and 1.8%C, 2.3%Si, added by different variety and trace amount of Cu, Mo, V and Ti. In addition, the corrosion resistance of lower-alloyed Low-carbon Ductile Iron with the ingredients of 1.4%C and respective 23%Si and 4.5%Si are researched as well.It is analyzed that the cracked surface characteristics and unwearing characters of Low-carbon Ductile Iron test samples for both rolling and impact friction. It is also discussed that the effect of variety and amount of alloy elements, graphite, hardness and impact value on the unwear property of Low-carbon Ductile Iron. The research results show that the unwear property is not only related to hardness, but also impact ductility. Furthermore, Low-carbon Ductile Iron with excellent unwear property should be the ideal combination of hardness and impact ductility. The unwear property would be enhanced somewhat as long as the spherical graphite in the material becomes more fine, round and well-distributed. The unwear property of Low-carbon Ductile Iron is dramatically superior to mat of annealed steel No.45 and 40Cr.The findings of corrosion resistance test show that lower-alloyed Low-carbon Ductile Iron, with good comprehensive properties and being easily-manufactured, has the ability to resist the corrosion of caustic soda and thick or light sulphuric acid. Fine, round and well-distributed spherical graphite will contribute much to the increase of corrosion resistance. The more they become fine, round and well-distributed, the more the ability of corrosion resistance of Low-carbon Ductile Iron will be enhanced.The author also put forward some suggestions for the use of Low-carbon Ductile Iron as unwearing and corrosion resistant materials.