CuO-Al铝热体系超重力熔铸W-Cu梯度复合材料

对添加W颗粒的CuO-Al体系的绝热温度进行了计算分析, 而后在超重力场中点燃添加20%质量分数W颗粒的CuO-Al铝热剂压块, 通过分析获得的W-Cu复合材料显微组织发现, W含量分布不均匀且质量分数较低。将纯W颗粒压片置于CuO-Al-W铝热剂压块底部, 超重力场中燃烧熔铸W-Cu复合材料, 对其进行显微组织、相结构及硬度分布的研究, 结果表明, 沿超重力方向材料底部W含量较低(60%~65%), 中部W含量较高(80%~89%), 顶部W颗粒呈链状、团簇状聚集状态且含量较低(<40%), 结合硬度及相结构的检测结果, 表明合金材料中沿超重力方向W成分呈连续梯度变化, 并对其成型机制进行了初步分析, 认为W成分连续梯度变化是由超重力燃烧熔铸工艺特点所决定的。

Inspection of W Cu gradient composites fabricated via combustion synthesis infiltration with CuO Al thermit under the ultra-gravity field

The adiabatic temperature of CuO-Al thermit adding W particles was calculated and analyzed. Thermit compact of CuO-Al with 20% mass fraction of W particles addition was ignited in the ultra-gravity field, through which the W-Cu composites was obtained. The results of microstructure inspection indicate that the low mass fraction of W displays inhomogeneous distribution. Along with the centrifugal direction, the compact of pure W particles is put under the compact of CuO-Al-W which can be ignited in the ultra-gravity field then the liquid Cu production with high temperature will infiltrate into the W compact. The inspection results of bulk W-Cu composites alloy indicate that the W mass fraction continuously gradient changes like: 60%-65% in the bottom, 80%-89% in the medium and low at the top(<40%), for inhomogeneous distribution with chains and clumps characteristic structure on the top. The hardness measurement and XRD inspection further verify the conclusion. The formation mechanism is also primarily analyzed and discussed, which indicates that W mass fraction continuously gradient variation is resulted in the characteristic aspects of the ultra-gravity SHS infiltration technique.