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钨—银触头合金的使用寿命由于钴的添加而得到改进。本文是研究 W—5%Co(重量)合金用银浸透和不用银浸透的显微结构和烧结作用。在钨—钴系统中,金属间化合物 Co_7W_6的形成是在钨钴接触点上。在银浸透的试样中,钴溶解于银中,通过液相作输送媒介使钴与钨微粒的纯净表面反应而成 Co_7W_6。以一种模型试验清楚地证明其结构,这种模型试验是以一小块钴板放在钨表面上并使液态银包围于四周:在热处理之后,钴覆盖了纯净的锫表面并以一种 Co_7W_6的覆盖层延伸,远远超过始初的钨钴接触面积。木文亦报导了热处理期间的尺寸变化并与理论推导进行比较。
The service life of tungsten-silver contact alloys is improved by the addition of cobalt. This article is a study of the microstructure and sintering of W-5% Co (weight) alloys impregnated with and without silver. In the tungsten-cobalt system, the intermetallic compound Co_7W_6 is formed at the tungsten-cobalt contact point. In silver-impregnated samples, cobalt was dissolved in silver and the pure surface of cobalt and tungsten particles reacted to form Co_7W_6 through the liquid phase as a transport medium. The structure was clearly demonstrated in a model test where a small piece of cobalt plate was placed on a tungsten surface and surrounded by liquid silver: After the heat treatment, the cobalt covered the surface of the nephew, Co_7W_6 coating extends far beyond the initial tungsten-cobalt contact area. Wood also reported dimensional changes during heat treatment and compared with the theoretical derivation.