摘要
利用膨胀法结合金相一硬度法，在Formast—F全自动相变仪上测定了60mm厚Q690D钢连续冷却转变静态CCT曲线．研究了冷却速度对显微组织、硬度的影响。结果表明：当冷速小于1℃／s时，转变产物为铁素体、珠光体和贝氏体；当冷速为1～3℃／s，转变产物为铁素体、贝氏体；当冷速为5～40℃／s，转变产物为贝氏体、马氏体；当冷速大于40℃／s时，转变产物为完全马氏体；当冷速小于20℃／s时，显微硬度逐渐升高；当冷速在20～100℃／s时，显微硬度在390HV左右。
The continuous cooling transformation static CCT curve of 60 mm Q690D steel was measured by Formast-F full automatic transformation instrument of expansion method and metallography-hardness method. The effects of cooling rate on the microstructure and hardness oft.he steel were analyzed. The results show that the austenite transformation products are ferrite, pearlite and bainite when the cooling rate is lower than 1 ℃/s. Those will be ferrite and bainite when the cooling rate is 1 43 ℃/s. Those will be bainite and martensite when the cooling rate is 5 -40℃/s and those will be completely martensite if the cooling rate is higher than 40℃/s. When the cooling rate is lower than 20℃/s ,the microhardness increases. The cooling rate is 20-100℃/s ,the microhardness is almost 390 HV.
出处
《热加工工艺》
CSCD
北大核心
2014年第10期54-56,共3页
Hot Working Technology
