喷射沉积连续挤压Al-20Si合金

摘要

采用喷射沉积连续挤压工艺制备Al-20Si合金棒料.结果表明不同的雾化颗粒因遗传熔体的不均匀性而出现成分差异,并对沉积坯内初晶硅分布有一定的影响,但是在挤压过程中这种分布不均现象会被消除.初晶硅在挤压过程中被破碎并随基体的流动而扩散;对不同挤压比制备的合金杆料进行微观组织观察,发现随着挤压比的增加,棒料内初晶硅更加细小弥散,尺寸均匀.合金室温抗拉强度也随着挤压比的增加而增加,挤压比为17时Al-20Si合金的抗拉强度达到195.6MPa.%Al-20Si alloy rods were fabricated by Spray Conform.The results show that the component of atomized particles is different due to the inhomogeneity of the melt,which could influence the distribution of primary silicon in the spray preform.However,the non-uniform phenomenon of atomized particles could be eliminated.The primary silicon is fragmented in the extrusion processing,and the fragments of primary silicon diffuse outwards with the flow of matrix.With the increase of extrusion ratio,the primary silicon became finer and more uniform and the tensile strength is increased.In addition,when the extrusion ratio is 17,the tensile strength of Al-20Si alloy reaches 195.6MPa.