Effect of Magnetically Treated Tap Water Quenchant on Hardenability of S45C Steel

Abstract The objective of this work was to investigate effects of magnetically treated tap water quenchant on hardenability and quenching crack resistance of S45C steel. The magnetically treated water quenchant was prepared by circulating regular tap water though a 130 mT magnetic field. The S45C steel was austenized at 860°C for 30 minutes. The hardenability in transverse section measurement of S45C steel quenched in magnetically treated tap water did not differ from that prepared with regular tap water quenchant. In measurements of the quenched end, the hardenability of S45C Steel quenched in magnetically treated water was below that with tap water quenchant. On the other hand, quenching crack resistance of S45C steel quenched in magnetically treated tap water was higher than that prepared with regular tap water. Moreover, microstructures of specimens quenched in magnetically treated tap water quenchant were different from that with regular tap water quenchant. Fine martensite structure formed in specimen quenched in regular tap water quenchant, while coarse lath martensite formed in specimens quenched in magnetically treated tap water quenchant.