激光熔覆金属陶瓷柱塞的研制

Development of laser ceramic alloyed plunger．

油田注水用高压柱塞泵柱塞服役工况恶劣，常用的喷焊Ni60+镍包WC金属陶瓷柱塞因涂层中及涂层与基体界面存在微观空隙和裂纹，易造成涂层块状剥落甚至大面积剥落，使涂层的设计性能未能充分发挥。研制的激光熔覆金属陶瓷柱塞，熔覆合金的优化组分是：C-Si-B-Re共晶合金粉末中加入30%WC粉末和25%TiC粉末；激光器窗口输出功率为2000～2400W，聚焦光斑直径35mm，扫描速度015～020m/min，扫描带搭接系数为03～04。现场试验表明，激光熔覆金属陶瓷柱塞的平均使用寿命达2700h，是喷焊柱塞的4～6倍。

The plunger of the high－pressure plunger pump for oilfield waterflood usually runs under bad working conditions． The common ceramic welded plunger has unsatisfactory wear－ and corrosion－resistance owing to microcosmic gaps and cracks in the coating and coating－matrix interface． Therefore a laser ceramic alloyed plunger is developed． The compositions of the coating are C－Si－B－Re eutectic alloy powder adding 30％ WC powder and 2．5％ TiC powder． The power output of the laser is 20004000W the diameter of the focusing light spot is 3．5mm scanning speed is 0．150．20m／min and the overlap coefficient of the scanning strip is 0．3～0．4． Field test shows that the mean service life of the laser ceramic alloyed plunger reaches 2700h 46 times of that of spray welded plungers．