Static CCT Curve Measurement and Microstructure Analysis of High Carbon Hard Wire 65 Steel
To explore the changes in microstructure and properties of high carbon hard wire spring steel rolled wire rod,and to guide the development of multi-stage temperature control cooling technology for rolled wire rod,static CCT curve measurement and microstructure analysis is conducted on 65 steel as the research object.The experimental results show that different cooling rates significantly impact the pearlite layer after austenite pearlite phase transformation in 65 steel.The air cooling line of rolled wire rod adopts a graded cooling process with a cooling rate of 5 to 10℃/s in the front section,the middle and rear ends of 1 to 5 ℃/s,and an outlet fan temperature above 570 ℃,which can obtain a microstructure with the layer spacing of 80 to 150 nm and a small amount of ferrite,achieve the optimization of the microstructure and synergistic of performance of hard wire steel.