A nano-indentation study of hot consolidated steel matrix composite

Steel matrix composites (SMCs) are quite interesting materials for high temperature applications due to synergetic effect of hard ceramic particles and ductile matrix. In the present article, 304 stainless steel matrix composites with 2–4 vol% TiB2 particles were produced by hot pressing route. Deformation behaviour of the composites under constant load was evaluated by conducting nanoindentation tests. Microstructural analysis revealed uniform distribution of particles in the matrix. Based on the load- penetration depth curve results, reduction in depth of around 12–28% was observed in 2 vol% and 4 vol% composites respectively compared to unreinforced steel. Use of TiB2 as reinforcement was found to be beneficial for improvement of strength and hardness as compared to their unreinforced counterpart. Composite with 4 vol% TiB2 resulted in highest strength and hardness owing to load carrying capacity of stiff reinforcement from the matrix. The plastic recovery of the composites was found to be decreased with increase in TiB2 content according to the calculation of plastic energy dissipation based on the nanoindentation results. It is expected that the observed results can provide a powerful platform for the design and production of steel based composites with desired mechanical properties.