Preparation of W/Cu functionally-graded materials by combustion synthesis melt-casting under ultra-high gravity

摘要

W/Cu functionally-graded materials were prepared by combustion synthesis melt-casting under ultra-high gravity. In the casted W/Cu samples, a clear gradient in chemical composition exists, showing an increasing W/Cu ratio from the top to the bottom. Each W/Cu sample can be divided into three areas, which are pure Cu, Cu-rich W/Cu alloy, and W-rich W/Cu alloy, respectively. The ultra-high gravity has a complex effect on the melt-casting process. A stronger ultra-high gravity filed can accelerate the phase separation but will cause more drastic turbulence in the melts, and thus moderate ultra-high gravity is appropriate to reduce residual Al203 in the W/Cu ingots.