微量硼对ZCuZn40Pb2组织和脱锌腐蚀性能的影响

Effect of Trace Boron on Microstructure and Dezincification Corrosion Properties of ZCuZn40Pb2 Alloy

用圆杯倾出法试验考察微量硼变质处理和未变质处理ZCu Zn40Pb2凝固界面的组织形貌,研究微量硼对ZCu Zn40Pb2铸态组织和脱锌腐蚀性能的影响。结果表明,加入微量的硼可以明显地细化ZCu Zn40Pb2铸态组织,影响凝固时凝固界面的组织形貌。未加硼的ZCu Zn40Pb2壳杯试样凝固界面的固相组织为粗化的α和β枝晶,固相界面粗糙。加入硼变质处理的壳杯试样凝固界面固相结晶组织形态为细小的等轴晶,组织细化,界面光滑。未加硼变质处理ZCu Zn40Pb2脱锌腐蚀严重,加入微量硼可以显著地阻止ZCu Zn40Pb2的脱锌腐蚀。

The solidification interface microstructures of ZCu Zn40Pb2 alloy after modification with trace boron and without modification are investigated by slush cup pouring testing. The effects of trace boron on as-cast microstructure and dezincification corrosion properties of ZCu Zn40Pb2 alloy are investigated. The results show that the as-cast microstructure of ZCu Zn40Pb2 alloy is evidently refined and the solidification interface structure is influenced by the addition of the trace boron. The solidification interface microstructure of slush cup without boron addition consists of coarse α phase and β dendrite and the inner surface of slush cup is coarse. The microstructure of slush cup with boron addition is the refined equiaxed crystal grain and the inner surface of slush cup is smooth. The dezincification corrosion of ZCu Zn40Pb2 alloy without boron addition is severe and it is remarkably inhibited by adding trace boron in the alloy.