Sintering of the Cu-Sn-P-MoS₂ Powder Composite at 780 °C

Abstract

The influence of the initial porosity of samples compacted from Cu + 9Sn + 1.5P + (5, 10, 15%) MoS₂ powder compositions and the amount of molybdenum disulfide MoS₂ on their growth during sintering in hydrogen at 780 °С is studied. It is established that their growth decreases with increase in the initial porosity of samples of the same sizes with equal MoS₂ contents and that their growth increases with a higher amount of MoS₂ in samples of the same sizes compacted to equal porosities. Water vapor that evolves during reduction of oxides present on the surface of the initial tin powder and copper–phosphorous alloy powder by hydrogen causes the swelling of samples. Moreover, phase transformations in the material during sintering can lead to an increase in the volume of samples as new phases are formed (copper sulfide Cu₂S) with a larger crystal lattice that that of the matrix and molybdenum disulfide.