Effect of heat treatment process on microstructure and properties of S47450 bolt

Abstract

The effects of heat treatment process on the microstructure and mechanical properties of S47450 bolt materials were studied by optical microscope (OM), scanning electron microscope (SEM), X-ray diffraction (XRD), tensile test, impact test and hardness test. The results showed that in the temperature range selected by the test, the quenched martensite of the bolt material after quenching at 1070 °C and tempering at 670 °C was fully refined and evenly distributed, and the precipitation of Cr23C6 played the role of precipitation hardening. It showed the excellent comprehensive mechanical properties, with the Brinell hardness reaching 295 HBW and the tensile strength of 1035 MPa. The elongation was 16 %, and the impact energy at room temperature was 21 J.

Effect of heat treatment process on Microstructure and properties of 4Cr13N corrosion resistant plastic die steel

“…Most of the nitrogen is dissolved in the matrix and enters the lattice gap as interstitial atoms, resulting in lattice distortion and solid solution strengthening, which is very beneficial to the hardness and corrosion resistance of steel. Second phase strengthening to further improve the strength and wear resistance of steel [8] . Based on the above analysis, 1020℃ is the most suitable quenching temperature.…”