Akademik Veri Yönetim Sistemi
Arabian Journal for Science and Engineering, cilt.50, sa.22, ss.19043-19061, 2025 (SCI-Expanded, Scopus)
In this study, the effects of intercritical annealing (ICA) temperature, martensite volume fraction (MVF), and martensite grain size (MGS) on the microstructure and mechanical properties of pre-alloyed powder metallurgy (PM) steel parts subjected to dual-phase (DP) treatment were investigated. Sintering (S), normalization (N), quenching (Q), and DP heat treatments were applied to the parts manufactured by warm pressing method. Afterward, mechanical testing and microstructure characterizations were carried out. A dual-phase microstructure with a homogeneous distribution in pre-alloyed PM steel parts was successfully produced with DP heat treatment. MVF and MGS increased as the ICA temperature increased. At the same ICA temperature, small MGS caused low MVF. DP heat treatment increased the strength and hardness of sintered pre-alloyed PM steel parts but decreased their ductility. As MVF increased at different ICA temperatures, strength and hardness increased but ductility decreased. In these samples, the highest strength of 241 MPa and the highest hardness of 174 HBW were obtained in SNDP-750 sample containing 48.87% MVF. This sample exhibited a low uniform elongation (0.68%). At the same ICA temperatures, as MGS of the samples got smaller, their strength and hardness increased but they exhibited a similar ductility. The highest strength of 242 MPa and the highest hardness of 169 HBW were observed in the SQDP-740 sample containing 2.91 μm MGS. This sample exhibited a uniform elongation of 2.15%. The results showed that DP heat treatment improved the mechanical properties of sintered pre-alloyed PM steels.