Highlights ? TaC and TiC particles, which act as promising second-phase particles, were used to improve the W matrix. ? Small amount of cracks and slight plastic deformation were observed on the surface of W-TaC. ? Slight plastic deformation was found in the W-TiC alloy. ? Thermal conductivity was the main factor for the changes in microhardness after heat loading. Abstract W, W-TaC, and W-TiC materials were subjected to heat–load tests in an electron beam facility (10 keV, 8 kW) at 100 pulses. After heat loading, severe cracks and plastic deformation were detected on the surface of pure W materials. However, plastic deformation was the primary change on the surfaces of W-TaC and W-TiC alloys. This phenomenon was due to the second-phase (TaC and TiC) particles dispersed in the W matrix, which strengthened the grain boundaries and prevented crack formation and propagation. In addition, the microhardness of W and W-TiC obviously decreased, whereas that of W-TaC did not change considerably before and after heat loading.
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