气压浸渗法制备ZrC-W-Cu复合材料的显微组织与力学性能

Microstructure and mechanical properties of ZrC-W-Cu composites prepared via gas pressure infiltration

为提高钨渗铜材料的性能以适应先进推进技术发展的需求,以ZrC粉和W粉为原料,采用无压烧结工艺制备ZrC-W多孔骨架,进而采用气压浸渗工艺对开气孔在20%左右的ZrC-W骨架压力渗铜,制备出ZrC-W-Cu复合材料。研究ZrC含量对ZrC-W骨架开气孔率、压缩强度及ZrC-W-Cu复合材料的显微组织和力学性能的影响规律。结果表明:随着ZrC含量(体积分数,下同)的增加,ZrC-W骨架的开气孔率先升高后降低,在ZrC含量为10%时开气孔率最大,为29.77%;ZrC-W骨架的压缩强度随ZrC含量的增加而下降,且整体低于W骨架;ZrC-W-Cu复合材料维氏硬度随ZrC含量的增加逐步增大,在ZrC含量为15%时达到3.26 GPa;弹性模量基本不变;断裂韧度随着ZrC含量的增加先升高后降低,抗弯强度在ZrC含量为4%时达到最大值,为1243 MPa。

In order to improve the performance of tungsten copper infiltration materials to adapt to the development of advanced propulsion technology,ZrC powder and W powder were adopted as raw materials to prepare ZrC-W framework by pressureless sintering process and the pressure infiltration of ZrC-W framework was conducted by pressure infiltration to prepare ZrC-W-Cu composites.The effect of ZrC content(volume fraction,the same below)on the porosity,compression strength,and microstructure as well as mechanical properties of ZrC-W-Cu composites were investigated.The results show that with the increase of ZrC content,the open porosity of ZrC-W framework increases first and then decreases,reaching the maximum value(29.77%)when ZrC content is 4%.The compressive strength of ZrC-W framework decreases with the increase of ZrC content,for which the compressive strength is lower than that of W framework.With the increase of ZrC content,the Vickers hardness of ZrC-W-Cu composites gradually increases and reaches 3.26 GPa when ZrC content is 15%.The elastic modulus remains unchanged basically,while the fracture toughness first increases and then decreases with the increase of ZrC content.The flexural strength reaches the maximum value up to 1243 MPa when ZrC content is 4%.