This paper studies the mechanical properties including hardness and elastic modulus of a novel TiB₂-TiC-TiNiFeCrCoAl high-entropy alloys (HEA) cermet using the nanoindentation method. For comparison, a commercial WC-Co cemented carbide was also studied. The results indicate that, under the loads between 4mN and 10mN, the TiB₂-TiC-HEA cermet has higher hardness in the range of ~28.4–33.8GPa (compared with ~22.3–26.2GPa for the WC-Co sample) however lower moduli in the range of ~416.9–456.6GPa (compared with ~466.0–516.5GPa for the WC-Co sample). Significant indentation size effects can be observed for both samples. Grains and phases influence the mechanical properties as well. With selected indentation positions on individual grains, under a load of 4mN, the mechanical properties of the TiB₂-TiC-HEA sample are scattered due to the multiple phases (TiC and TiB₂) and different facets. Among such results, there are two groups which have similar properties within each group. For comparison, the WC-Co sample shows two groups of results on the individual grains, which are correlated to the different facets of WC. Compared between these two samples, the hardness of the two groups of TiB₂-TiC-HEA(~36.6 ± 2.8GPa and 30.2 ± 2.6GPa), are also higher than the two groups of WC-Co (~30.7 ± 2.5GPa and 25.0 ± 3.9GPa).

本文采用纳米压痕法研究了新型TiB ₂ -TiC-TiNiFeCrCoAl高金属合金（HEA）金属陶瓷的力学性能，包括硬度和弹性模量。为了进行比较，还研究了商用WC-Co硬质合金。结果表明，在4mN至10mN的载荷下，TiB ₂-TiC-HEA金属陶瓷的硬度较高，在〜28.4–33.8GPa范围内（而WC-Co样品的硬度为〜22.3–26.2GPa），而模量较低，在〜416.9–456.6GPa的范围内（相比〜466.0– WC-Co样品为516.5GPa）。两种样品都可以观察到明显的压痕尺寸效应。晶粒和相也影响机械性能。在4mN的载荷下，在单个晶粒上选择了压痕位置后，TiB ₂ -TiC-HEA样品的机械性能由于多相（TiC和TiB ₂）和不同的方面。在这些结果中，有两组在每一组中具有相似的性质。为了进行比较，WC-Co样品在单个晶粒上显示了两组结果，这些结果与WC的不同方面相关。对比这两个样品，两组TiB ₂ -TiC-HEA的硬度（〜36.6±2.8GPa和30.2±2.6GPa）也高于两组WC-Co（〜30.7±2.5GPa和30.2±2.6GPa）。 25.0±3.9GPa）。