Study on Improving Impact Toughness and Friction Welding Technology of Ductile Cast Iron

　　Study on Improving Impact Toughness and Friction Welding Technology of Ductile Cast Iron
　　The way of improving room-temperature and low-temperature impacttoughness of ductile cast iron has been studied in this article. Reasonablenodularization and inoculation technology were established through someexperiments. The effects of heat treatment, Block neodymium magnet chemical composition and coolingspeed on structure and impact toughness of ductile cast iron have been analyzed.The results achieved are: Nodularization treatment used RE-Mg nodularizer,the amount of which was 1%. Inoculation treatment used 0.6%75SiFe in ladleinoculation.
　　The way of fast cooling was adopted. The technique ensured theeffects of nodularization and inoculation. Spherical graphite gained was small andthe number of spherical graphite was more. Ductile cast iron gained ferrite baseby two-stage annealing. At the same time, room-temperature and low-temperatureimpact toughness of ductile cast iron were excellent when chemical compositionwas 3.3～3.7%C,1.5～2.0%Si,Mn≤0.2%,S≤0.03%,P≤0.07%.The http://www.chinamagnets.biz friction welding of ductile cast iron and low carbon steel has been stillexplored in this article. The weldability and mechanical property of the weldingjoints have been studied. The results show that under certain welding parameter,the joints of ductile cast iron and low carbon steel were sound, and the joints hadadequate strength. So the friction welding was fit for ductile cast iron and lowcarbon steel.