Zn对斯特林银组织和性能的影响

Influence of Zn on the Microstructure and Properties of Sterling Silver

系统研究了Zn对斯特林银的铸造、冷加工、抗电化学腐蚀、抗硫化变色和抗氧化红斑等性能的影响。试验结果表明,适量的Zn可以改善铸造性能,抑制斯特林银中出现缩松缺陷,有助于获得致密的铸态组织,并有利于改善合金的抗电化学腐蚀、抗硫化变色和抗氧化性能。但是Zn量超过约3.5%后容易产生晶粒粗化和氧化夹杂物,并使抗电化学腐蚀和抗硫化变色性能略有下降;Zn不利于斯特林银硬度的提高,其含量越高,合金的铸态硬度越低;Zn含量在2.5%以内时合金有较好的冷加工性能,超过此值后会造成一定程度的损害。

Influence of Zn on the properties of as-cast, cold working, electrochemical corrosion resistance, anti-tarnish of sulfuration and anti-oxidation of sterling silver were researched. The results show that with proper Zn addition, as-cast property of the sterling silver is improved, and shrinkage porosity is decreased, and compact microstructure in the silver can be observed. However, Zn addition is harmful for the improvement of the hardness of the sterling silver. With Zn addition less than 3.5%, the silver alloy exhibits acceptable cold working performance, electrochemical corrosion resistance and anti-tarnishing as well as oxidation resistance, in which, the more the Zn addition is, the better the anti-tarnishing of sterling silver is. However, with the Zn addition more than 4.5%, the cold working is deteriorated, and electrochemical corrosion resistance and anti-tarnishing are slightly decreased.