制备工艺对等离子炬阴极使用寿命影响的研究

Influence of Preparation Process on Operating Life of Plasma Torch Cathode

研究了采用熔化-塑性变形-机械加工的传统工艺和真空熔铸近终成形新工艺制备等离子炬阴极,用光学显微镜观察了两种工艺制备的阴极微观组织,发现采用传统工艺制备的阴极内部存在空隙、晶粒粗大且含有夹杂物;采用新工艺制备的的阴极内部致密、晶粒细小且无夹杂物。而这些组织特征正是等离子炬阴极所必须的,并且此工艺简单,节省原材料。采用新工艺制备的阴极使用寿命较传统工艺制备的阴极有大幅度提高。

Plasma torch cathode was prepared by melting-plastic deformation-machining technology and near net shape technology as fusion casting in vacuum. The microstructure of the cathode prepared by two kinds of technology was observed by light microscope. The results show that the cathode prepared by traditional technology has internal void, coarse grains and inclusion. The cathode prepared by new technology has compact structure, fine grain and no inclusions. The characteristics of the microstructure are required as plasma torch cathode. The technology of fusion cast in vacuum is extremely simple and can save a lot of raw materials. The operating life of cathode prepared by new technology is improved vastly, compared with traditional technology.