含氮马氏体不锈钢420U6冷轧板再结晶退火的热模拟试验

Therm-Simulation Test on Recrystalization Annealing Process of Cold Rolled Plate of Nitrogen Bearing Martensitic Stainless Steel 420U6

采用Gleeble-3800热模拟试验机并结合硬度法与金相法分别测定了压下率66%含氮马氏体不锈钢420U6的1 mm冷轧板定时条件下的再结晶温度和恒温条件下的再结晶时间,通过Arrhenius公式计算了试验钢的再结晶激活能。试验结果表明,当保温时间为60 s时,试验钢的再结晶温度为664.2℃当退火温度为780℃时,再结晶时间为7. 7 s;再结晶激活能Qr为145. 3 kj/mol。

A 1 mm cold rolled plate of nitrogen bearing martensitic stainless steel 420U6 with reduction 66% was simulated-annealed by the Gleeble-3800 thermo-simulation machine, the recrystallization temperature under a constant holding time and the recrystallization time under a constant temperature were determined respectively by hardness method and metallographic examination, the recrystallization activation energy of the test steel was calculated according to Arrhenius equation. Test results showed that the recrystallization temperature in steel was 664. 2 ℃ when holding time was 60s;the recrystallization time in steel was 7. 7 s when annealing temperature was 780℃;and the calculated recrystallization activation energy Qr was 145. 3 kJ/mol.