Effect of quenching baths on microstructure and hardness of AISI1035 steel

In this study, influence of quenching baths on microstructure and hardness of AISI 1035 steel has been investigated. Two categories of quenching baths including water and oil based baths were selected. Water based baths include tape water, distilled water, brine solution, saline water and sodium hydroxide solution while oil based quenching baths include fish oil, coconut oil, olive oil, used engine oil and quench 310 oil. Microstructure and vicker hardness were characterized by optical microscopy and micro vicker hardness tester. Results showed that water based quenching baths exhibit higher hardness values due to formation of larger fractions of martensite with small fractions of retained austenite, whereas oil based baths produced moderate hardness values due to formation of bainite, pearlite with retained austenite structures.Keywords: Quenching; Martensite; Retained Austenit