我厂在1950年初曾试验用磷青铜铸造火车气刹 车的三通阀主活塞环,其后又用以铸造2公尺立式车 床的花盘转轴大铜布司、铜华姆牙轮等,在提高铸件组 织　密度、硬度、强度及韧性方面,获得一定的成效。但 在试铸之初,因有关铸造磷青铜方面的资料甚少,且磷 铜无法买到(须自制),因此 At the beginning of 1950, our factory had experimented with the three-way valve main piston ring made of phosphor bronze for brake gas brake, and later used for casting the large brass cloth and copper bronze cone of the 2-meter vertical lathe, Improve casting density, hardness, strength and toughness, to obtain a certain effect. However, at the beginning of the trial-casting process, there was very little information on casting phosphor bronze and the phosphor bronze was not available