热压烧结法制备W-Cu/AlN复合材料的组织与性能研究（英文）

Structure and Properties of W-Cu/Al N Composites Prepared via a Hot Press-Sintering Method

采用高能球磨技术制备W-30%Cu(质量分数)纳米晶粉体,再通过球磨混粉的方法添加不同质量分数的纳米AlN颗粒,然后采用热压烧结法得到W-30Cu/x%AlN复合材料。研究并比较了纳米AlN的加入对材料组织结构、物理以及力学性能的影响。结果表明,W-30Cu/x%AlN复合材料都有较致密和均匀的组织结构,AlN的添加,细化了烧结体中W颗粒;纳米AlN颗粒的添加提高了复合材料的硬度,但是随着AlN纳米颗粒含量的增加,基体晶界上的增强相颗粒分布过多,而使材料的抗弯强度有所下降;少量纳米AlN颗粒(≤1%)的添加有利于W-Cu复合材料的热导率提高,随AlN添加量的增加,复合材料的电阻率升高,电导率下降。

W-30wt%Cu nano-crystalline powder was prepared by high-energy ball-milling,and then different mass fractions of A1 N nanoparticles were added to the powder via the ball-milling.Finally W-30Cu/x%A1N composites were obtained by hot press-sintering process.The microstructures,the physical and mechanical properties of as-sintered composite samples were studied.The results indicate that the W-30Cu/x%A1N composites possess denser and more uniform microstructure.Moreover,the degree of refinement of W particles and the hardness of the composites increase with the addition of AlN,but the bending strength decreases with increasing of AlN nanoparticles due to the nanoparticles excessive distribution on the grain boundaries of the matrix.It is beneficial to increase thermal conductivity of W-Cu composites,when the content of AlN nanoparticles is ≤1%.Resistivity of the composites increases with increasing the amount of AlN nanoparticles,but the conductivity of the composites declines.