高熵合金CoCrFeNiTiAl粘结WC硬质合金的制备与研究

Preparation and research of high-entropy-alloy CoCrFeNiTiAl bonded WC cemented carbide

通过放电等离子烧结成功制备了高熵合金CoCrFeNiTiAl作为粘结相的WC基硬质合金。研究了WC-CoCrFeNiTiAl材料的致密化行为、相组成、显微组织和力学性能,并与WC-Co材料进行了对比。在1200℃烧结后,获得的WC-CoCrFeNiTiAl试样显微组织致密。在室温下,WC-10%CoCrFeNiTiAl试样的硬度为20.06 GPa,比WC-10%Co试样高出18.1%。在600/800℃温度下,WC-CoCrFeNiTiAl试样表现出优异的抗软化性能,硬度比WC-Co高40.6%~46.5%。WC-CoCrFeNiTiAl硬质合金在800℃以内良好的抗高温软化性能主要归因于CoCrFeNiTiAl固溶体的扩散缓慢现象。

WC based cemented carbide bonded by high-entropy-alloy CoCrFeNiTiAl was successfully fabricated by spark plasma sintering.The densification behavior,phase constitution,microstructure and mechanical properties of WC-CoCrFeNiTiAl composites were studied and compared with WC-Co.After sintering at 1200℃,the WCCoCrFeNiTiAl specimens show dense microstructures.At room temperature,the hardness of the WC-10%CoCrFeNiTiAl specimen is 20.06 GPa,which is 18.1%higher than that of the WC-10%Co specimen.At 600/800℃,the WC-CoCrFeNiTiAl specimens exhibit excellent softening resistance,and their hardness is 40.6%~46.5%higher than that of the WC-Co specimen.The good high temperature softening resistance of WC-CoCrFeNiTiAl cemented carbide within 800℃is mainly attributable to the diffusion retardation of CoCrFeNiTiAl solid solution.