微/纳米Cu-W粉末激光烧结体的显微组织

MICROSTRUCTURES OF LASER SINTERED MICRON/NANO-SIZED Cu-W POWDER

研究了激光烧结工艺条件下微/纳米Cu-W粉体致密化的过程及对显微组织的影响.结果表明,合理增加激光功率或降低扫描速率,可提高烧结致密度及组织均匀性;降低扫描间距至0.15 mm,可改善烧结表面光洁度;铺粉厚度降至0.15 mm,可提高烧结层间结合性.经工艺优化,最高成形致密度达到95.2%,且在烧结组织中形成一系列规则的W环/Cu芯结构;并探讨了该结构的成形机制.

Effects of processing conditions on densification behavior and microstructural features of laser sintered micron/nano-sized Cu W powder mixture were investigated. Reasonable increase in the laser power or decrease in the scan speed leads to a higher sintered density and a more homogeneous microstructure. Decreasing the scan line spacing to 0.15 mm improves the surface finish of the sintered component. Lowering the powder layer thickness to 0.15 mm yields a more coherent inter-layer bonding. Under the suitable processing conditions determined, the highest densifieation level reaches 95.2%. A series of regularly shaped W-ring/Cu-core structures are also formed＇ in laser sintered component, and the forming mechanism was discussed.