新型无铅黄铜的耐蚀性能研究

采用脱锌腐蚀深度测量方法、光学显微镜、SEM和XRD等分析方法，研究了镁锑黄铜的脱锌腐蚀性能和添加少量Sn、Al元素对其耐腐蚀性能的影响。结果表明，镁锑黄铜的脱锌腐蚀首先发生在暴露于基体表面的β相，然后通过α相界扩展到另一个β相；当α相周围的β相和α相界脱Zn完全后，α相开始脱Zn。加Sn后，一方面强化了晶界，阻滞了α相的脱锌；另一方面Sn和Cu、O等元素构成了成分复杂的致密保护膜，阻止了基体Zn的溶解，有效地提高了镁锑黄铜的抗腐蚀性能。

Study on Corrosion Resistance of New Unleaded Brass

In this paper,the dezincification corrosion resistance of Mg-Sb brass was investigated by the methods of dezincification corrosion depth testing,optical microscope,SEM and XRD. The results show that the dezincification corrosion of Mg Sb brass starts firstly on β-phase,then it diffuses to another β-phase along the grain boundaries of a-phase. The α phase will corroded resistance after its grain boundaries and β-phases around it corroded completely. Sn element improves the corrosion resistance of Mg Sb brass effectively. On one hand,Sn element can enrich at grain boundaries, block the dezincification of α-phases,on the other hand,a dense protective film hinder the dissolution of Zn, which is composed of Sn,Cu and O elements.