摘要
采用热膨胀法结合金相-显微硬度法,在Gleeble-1500热模拟试验机上测定了弹簧钢55SiCrA的相变临界点Ac1、Ac3、Ar1、Ar3和Ms;同时测定了奥氏体在不同冷却速度下连续转变时的膨胀曲线,并绘制了动态连续冷却转变曲线(CCT图);通过FE-SEM研究了不同的冷却速度对显微组织形貌和珠光体片层间距的影响。结果表明:随着冷速的增加,珠光体片层间距减小,显微硬度值增大;弹簧钢55SiCrA线材控制冷却理想的冷速范围为0.5～1℃/s。
The critical temperatures,such as Ac1,Ac3,Ar1,Ar3 and Ms of spring steel 55SiCrA were determined by dilatometric change combined with metallographic test and microhardness measurement on a Gleeble-1500 thermal mechanical simulator.By measuring the dilatometric curves of supercooled austenite continuous cooling transformation at different cooling rates,dynamic CCT diagram was obtained.The effects of different cooling rates on microstructure and pearlite lamellar specing were studied by FE-SEM.The results show that with the increasing of cooling rate,the pearlite lamellar spacing decreases and microhardness of pearlite increases.The optimum cooling rate of spring steel 55SiCrA wire is recommended in the range of 0.5 ℃/s to 1 ℃/s.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2011年第7期73-77,共5页
Transactions of Materials and Heat Treatment
关键词
弹簧钢55SiCrA
连续冷却转变
CCT曲线
片层间距
热模拟
spring steel 55SiCrA
continuous cooling transformation
CCT curves
lamellar spacing
thermal mechanical simulation
