进行了W-Cu复合材料的激光直接成形实验,研究了混合粉末均匀性和W粉的形态对激光直接成形W-Cu复合材料成形质量的影响, 对成形试样的微观组织进行了分析, 并测量了成形件的致密度。研究结果表明,当混合粉末均匀性较差时, 成形气孔主要是由W粉末颗粒团聚引起, 且随着激光功率的增大, 成形气孔数量增多, 成形件的致密度减小。使用直径为54~100 μm的球形W粉,由于粉末流动性好, 成形试样的致密度大于99%; 使用直径为25~54 μm的球形W粉, 由于送粉过程中粉末飞散, 成形试样Cu、W分布不均匀, 成形试样表面凹凸不平。

The experiments of laser direct forming W-Cu composites are conducted. The effects of W-Cu powder-mixing homogeneity and W-powder morphology on the forming quality in the laser direct forming of W-Cu composites are studied. The microstructures of forming samples are analyzed and the relative density of forming samples is measured. The study results show that the pores of forming samples are mainly caused by the agglomeration of W-powder particles, and the number of pores increases with the increase of laser power which leads to the decrease of the relative density of forming samples. By using the spherical W-powder with diameter of 54-100 μm and as a result of good fluidity, the forming sample has a relative density of larger than 99%. By using the W-powder with diameter of 25-54 μm and as a result of powder-flowing-apart during the powder-delivering process, the nonuniform distributions of W and Cu and uneven surface in the forming sample occur.