Effects of Controlled Rolling and Controlled Cooling Technological Parameters on Microstructure and Mechanical Properties of 65Mn Hot Rolled Strip Used for Metallurgy Saw Blade

The effects of controlled rolling and controlled cooling technological parameters(start rolling temperature, finish rolling temperature, coiling temperature and cooling rate after coiling) on microstructure and mechanical properties of 65Mn hot rolled strip were studied, and the best controlled rolling and controlled cooling technological parameters were obtained. The results show that, under the conditions of higher start rolling temperature, higher finish rolling temperature, higher coiling temperature and lower cooling rate after coiling, the original austenite grain size and pearlite interlamellar spacing of 65Mn steel were larger, and the tensile strength and hardness were lower. The cooling rate after cooling had the most obvious effects on microstructure and mechanical properties. The best controlled rolling and controlled cooling technological parameters as follows, start rolling temperature was (1 180±10) ℃, finish rolling temperature was (910±10) ℃, coiling temperature was (710±10) ℃ and cooling rate after coiling was less then 0.05 ℃·min-1.