Effects of Nano TiC on the Microhardness and Friction Properties of Laser Powder Bed Fusing Printed M2 High Speed Steel

Abstract

In this work, TiC/M2 high speed steel metal matrix composites (MMCs) were prepared using the ball milling method and laser powder bed fusing process. By controlling the TiC content in TiC/M2HSS, the grain size, phase composition, and frictional wear properties of the samples were enhanced. The results showed that when TiC/M2HSS was supplemented with 1% TiC, the surface microhardness of the samples increased to a maximum value and the wear volume decreased by approximately 39%, compared to pure M2HSS. The hardness and friction wear properties of the TiC/M2HSS composites showed a decreasing trend as the TiC content increased, owing to an increase in internal defects in the samples, as a result of excess TiC addition. The physical phases of the TiC/M2HSS MMC samples prepared by LPBF were dominated by the BCC phase, with some residual FCC phases and carbide phases. This work explored the possibility of enhancing the frictional wear performance of TiC/M2HSS samples by controlling the TiC content.

Study of morphological, physical and mechanical properties of thin NbN films synthesized via DC magnetron sputtering system

“…Figure 4 shows Vickers microhardness of NbN/SS304 films synthesized like a function of the power, where the average hardness values are obtained from three indentations for each sample. The inset demonstrates the image SEM of the indentation of NbN/SS304 film at 100 W. The values of microhardness were increased from 20.2 to 25.6 GPa with increasing power (Figure 4); we can explain the increase of microhardness due to increase of deposition rate and/or decrease the grain size because the defects (dislocation) increase where the grain size decrease and consequently the stress and increase of microhardness (Liu et al , 2022).…”

“…Figure 4 shows Vickers microhardness of NbN/SS304 films synthesized like a function of the power, where the average hardness values are obtained from three indentations for each sample. The inset demonstrates the image SEM of the 4); we can explain the increase of microhardness due to increase of deposition rate and/or decrease the grain size because the defects (dislocation) increase where the grain size decrease and consequently the stress and increase of microhardness (Liu et al, 2022). Sandu et al (2006) found that the dependence of hardness of the films on the structural phase, they were obtained the hardness from 35 GPa (for hexagonal b phase) to 40 GPa (for d 0 phase), where it was about 25 GPa for the cubic d phase, which is in agreement with our results due to the same structural phase.…”