Densification and structural change of mechanically alloyed W-Cu composites

摘要: Fine-grained, high-density (97+ pct of theoretical density (TD)), 80W-20Cu wt (58W-42Cu at. pct) composites have been prepared using nonconventional alloying techniques. The W and Cu precursor powders were combined by a high-energy ball-milling procedure in air or hexane. mechanically alloyed W+Cu powder mixtures then cold pressed into green compacts sintered at 1523 K. milling medium time varied to increase product densities with concomitant order-of-magnitude decrease grain size. For densification, was found be more effective than From microhardness measurements, it concluded that the W-Cu alloys dispersion solution hardened, but sensitive entrapped residual impurities. X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron micros-copy (SEM) analyses used demonstrate as-milled alloy structures metastable, decomposing starting components upon heating above 723