斯特林银形成红斑的机理探讨

Formation Mechanism of Firescale on Sterling Silver Alloy

斯特林银合金在铸造、焊接等热加工时,容易形成红斑。运用X射线衍射仪、金相显微镜等仪器对红斑组织进行了研究,探讨了红斑形成的机理。研究结果表明,斯特林银合金加热时,发生了Cu的选择性氧化形成Cu2O和CuO,其氧化组成分为外氧化层和内氧化带,酸浸时内氧化物难于去除,抛光后即呈现为红斑。

Sterling silver alloy was susceptible to form firescale in heat working,such as casting and welding.The formation mechanism of firescale in the sterling silver alloy has been discussed by analyzing the firescale structure using XRD and OM.The results show that the copper is oxidized selectively to form cuprous or cupric oxide on the surface with sterling silver alloy heated,including outer oxidization layer and inner oxidization layer.However,the inner oxidization layer would be left during the oxidized samples pickled in dilute sulfuric acid,which exhibits firescale after the sample polished.