原位生成Al_2O_3/Cu复合材料的新工艺

NEW PROCESSING FOR PREPARING Al_2O_3/Cu COMPOSITE BY IN SITU REACTION

采用一种新型工艺制备了Al2O3/Cu复合材料。高能球磨制备亚稳态的Cu-0.8wt%Al合金粉,再将Cu2O粉与其一起进行高能球磨,然后将复合粉末压坯在真空炉中同时进行氧化和烧结。该工艺省略了还原剩余Cu2O的环节,氧化和烧结时间仅为1h。生成的Al2O3的粒径约250nm,颗粒间距约500nm,均匀弥散分布;该材料冷加工后性能接近SCM制品性能。该配比的Al2O3/Cu复合材料的热稳定性良好,在800℃下循环冷淬20次无裂纹;软化温度为700℃。

A CuAl2O3(1.5 wt% or so) composite was successfully prepared by using a new approach, which includes high energy milling of Cu and Al powder to produce CuAl alloy powder, high energy milling of the CuAl alloy powder together with Cu2O powder, and preparing Al2O3/Cu composite through conducting oxidation and sintering synchronously in vacuum. The peculiarities of this approach are that the reduction of superfluous Cu2O is left out, and the period of reacting and sintering is only 1 hour. It was observed that the Al2O3 particles uniformly dispersed in the copper matrix with an average size of 250 nm in diameter and particles space between 500 nm. The properties of Al2O3/Cu composite are close to those of SCM products after cold working. The Al2O3/Cu composite possesses excellent thermal stability since there are no cracks observed after exposing to 800℃ and then cold quenching, which is cycled 20 times. The intenerating temperature of Al2O3/Cu composite is about 700℃.