Investigation of structural, mechanical, and corrosion properties of steel 316L reinforcement by hBN and TiC particles

Abstract

The powder metallurgy process is commonly used to produce nanocomposite samples so that, their properties depend on the process parameters and the weight fraction of reinforcements. In the current study, producing metal matrix nanocomposite with steel 316L as a matrix and mixing of hBN/TiC nanoparticles as a reinforcement is conducted. The total weight percentages of reinforcements are 6% wt and 8% wt (i.e. with an equal proportion for each nanoparticle). The powders were mixed for 10 h and then compacted at different pressures (300 MPa and 400 MPa) by cold isostatic pressure (CIP) conditions. The compacted powders were sintered at different temperatures (1350 °C and 1450 °C), and times (2 h and 4 h) in the furnace. The microstructural analysis of nanocomposite was performed by SEM, XRD, EDX, DTA, and also FT-IR tests. The results showed that by increasing the weight fraction of nanoparticles the microhardness and wear rate improved and, on the contrary, the flexural strength and corrosion rate decreased. The optimum result for the microhardness and wear rate were achieved when the sample contains 8% wt nanoparticles, compacted at 400 MPa and sintered at 1350 °C for 4 h. As well, the highest flexural strength and corrosion rate belong to the sample compacted and sintered at 400 MPa, 1450 °C for 2 h.