钨铜触头材料的热等静压处理

HIP TREATMENT OF W-Cu CONTACT COMPOSITES

研究了钨铜触头材料的热等静压(HIP)处理。触头材料通过混合、压制、预烧结、熔渗制成。在低于铜的熔点温度和90～100MPa压力下进行HIP。试验结果表明,对于W60Cu40触头材料,HIP后密度由12.7～12.8g/cm_3高到13.2～13.3g/cm_3;硬度由HRB50～70提高到HRB80;抗弯强度由550～750MPa提高到高于1000MPa,电导率可以稳定地达到大于60％IACS。认为钨铜的HIP可以消除工件中的疏松、缩孔和熔渗缺陷,其机制与热等静压铸造合金相似。对于具有连通至表面的上述缺陷,则热等静压无效。试验结果也表明,从提高密度考虑,对于含铜低至20％左右的钨铜材料,HIP也有良好效果。

W-Cu contact materials treated by HIP have been investigated Contact materials were made by mixing, pressing, presintering and infiltrating. HIP was conducted at the temperature below melting point of copper and under the pressure of 90-100 Mpa. It has been proved that the density of W60Cu40 contact material after HIPing can be increased from 12.7-12.8g/cm^3 to 13.2～13.3g/cm^3,hardness from HRB 50-70 to HRB80, bending strength from 5.5～7.5×10~2 Mpa to more than 1×10~3 Mpa and electric conductivity can be stably over 60% IACS. It is considered that the defects such as loose contact, shrinkage porosity and weak points of infiltration in workpieces can be elemented by HIPing. The mechanism of HIPing W-Cu contact materials is analogous to that of casting alloy. HIPing shows no effects for above mentioned defects, if they communicate to the surface. Experiments also showed that in increase of density HIPing had good effects for W-Cu materials with low copper contents of 20%.