球墨铸铁抗腐蚀性和抗生长性研究

Research on Corrosion Resistance and Growth Resistance of Nodular Cast Iron

汽车排气歧管工作在高温环境中,要求其材料具有更加优异的性能。制备了两组不同化学成分的球墨铸铁试样,对它们的铸态组织与构成进行了研究。利用电化学综合测试系统测试了Na Cl溶液中球墨铸铁的腐蚀电流和电位;研究了球墨铸铁试样在不同工作温度下的增长情况。实验与分析结果表明,高镍球墨铸铁的抗腐蚀性能和抗生长性能均优于高硅钼球墨铸铁,更加适合作为汽车排气歧管材料。

Two groups of ductile cast iron samples with different chemical compositions were prepared, and the microstructure and chemical composition of the cast iron samples were studied. The corrosion current and potential of the samples in NaC1 solution was tested by electrochemical synthesis test system. And the growth of ductile cast iron samples under different working temperatures was studied. Experimental and analytical results show that the corrosion resistance and growth resistance of high nickel ductile cast iron are superior to that of high silicon molybdenum ductile iron, and more suitable for automobile exhaust manifold.