HC1150/1400MS马氏体钢的高温本构模型  

Constitutive model of HC1150/1400MS martensitic steel at high temperature

作　　者：林潇[1] 张清东[1] 

机构地区：[1]北京科技大学机械工程学院,北京100083

出　　处：《金属热处理》2017年第10期197-202,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(51575040)

摘　　要：利用Gleeble1500热模拟试验机在温度范围600~900℃、应变速率范围10-2~10 s-1等对HC1150/1400MS马氏体钢试件进行等温拉伸试验,进而构建了马氏体钢热加工过程的数值模拟需要的高温本构模型,用以根据应变、应变速率及变形温度预测流动应力。试验得到该材料奥氏体组织在不同温度及应变速率下的真应力、真应变曲线,显示材料的流动应力随变形温度的降低和应变速率的提高而增大,随变形温度的升高和应变速率的降低而减小。选用修正的Arrhenius双曲正弦模型对其高温力学行为进行描述,采用四次多项式拟合获得Arrhenius本构方程中参数α,β,n1,n,ln A,Q与应变的对应关系,最终确定包含变形温度及应变速率的流变应力计算方程。采用拟合度表示计算应力与实测应力的相关性,拟合度结果表明该本构模型对HC1150/1400MS马氏体钢高温流动应力的预测较准确。Isothermal uniaxial tensile tests were conducted by Gleeble1500 thermal simulator for a martensitic steel HC1150/c1400 MS at the temperature range of 600-900 ℃ and the strain rate range of 10^-2-10 s^-1,then constitutive equations for the steel were established to predict the flow stress based on strain,strain rate and deformation temperature. As results,the true strain-stress curves of martensitic steel in austenite state under different temperatures and strain rates were gained. The experiment results show that the decrease of deformation temperature and the increase of strain rate can both lead to the increase of flow stress,and vise verse. The modified Arrhenius model is used for the description of austenite mechanical behavior under high temperatures. Equations of quartic polynomial are used to express the relations between constitutive equation parameters α,β,n1,n,ln A,Q and the strain,which finally determine the stress prediction equation concerning the deformation temperature and the strain rate. The calculated degree of data fitting indicates that the constitutive equations so obtained is relatively accurate for the prediction of HC1150/1400 MS martensitic steel flow stress under high temperatures.

关 键 词：马氏体钢 HC1150/1400MS 本构关系 热变形 等温拉伸 

分 类 号：TG142.1[一般工业技术—材料科学与工程]