美国弗吉尼亚阿灵顿海军研究所以史蒂文·菲斯曼为首的研究人员经巧妙改进 ,在过去传统锻铸法的基础上发明了新的“沉淀铸造法”。即以铝、铜铸件为母体 ,在关键部位 ,诸如磨耗系数最大的推进器传动轴 ,在轴外层加上薄薄一层含75 %碳钨合金膜 ,则使其抗磨性大增。《沉淀法》灌 Researchers led by Steven Fessman at the Arlington Naval Research Institute in Arlington, Virginia, have made clever improvements and invented the new “precipitation casting method” based on the traditional forging casting method. That is, aluminum, copper castings as the parent body, in key parts, such as the friction coefficient of the largest propeller drive shaft in the outer layer with a thin layer of 75% carbon-tungsten alloy film, the wear resistance so greatly increased. “Precipitation Law” irrigation