初始状态对65盘条钢热变形行为的影响北大核心CSCD

采用Gleeble-3500热模拟试验机,在温度为850~1 050℃,应变速率为0.01~50s-1范围内,对65盘条钢铸态和轧态进行热压缩试验,研究了2种初始状态对65盘条钢热变形行为的影响。分析了不同变形条件下65盘条钢的流变曲线、金相组织,计算了铸态与轧态的激活能,建立了不同初始状态下的变形抗力模型。结果表明:不同初始状态对65盘条钢的热变形行为影响较大。2种状态下的真应力-应变曲线均表现出对温度和应变速率的敏感性,轧态流变应力在应变约为0.6之前大于铸态,之后趋于一致,在相同的变形条件下轧态的峰值应力均高于铸态。2种状态下建立的周纪华-管克智本构方程表明轧态基准变形抗力值大于铸态,分别为165.07和147.05MPa。

Effect of initial state on hot deformation behavior of 65 wire rod

In order to study the influence of two initial states on the hot deformation behavior of 65 wire rod, the deformation behavior of the as- cast and as- rolled 65 wire rod was investigated in the deformation temperature range from 850?? to 1050??, the strain rate range from 0. 01s-1 to 50. 0s-1 by the Gleeble- 3500 simulator. The flow curves and microstructure of 65 wire rod steel under different deformation conditions were analyzed. The activation energies of the as- cast and rolled states were calculated. The constitutive equation under different initial conditions was established. The results show that different initial conditions have a great influence on the thermal deformation behavior of 65 wire rod. The flow curves of the two states show sensitivity to temperature and strain rate. The flow stress at as- rolled is larger than the as- cast state before the strain is about 0. 6. The peak stress of the as- rolled is higher than that of the as- cast. The constitutive equation is established for both states, and the value of the base slip resistance in the as- cast state is larger than that of the as- cast state, which are respectively 165. 07MPa and 147. 05MPa.