摘要
以凝固过程的溶质微观偏析理论为基础,通过实际测试和理论分析计算相结合,系统的研究了连铸条件下SS400和65Mn两钢种的高温热力学特性。研究表明:钢种两相区宽度对其相应的等效导热系数、等效比热2个热学参数和泊松比起决定作用;通过铸态组织的高温拉伸试验测试结果可拟合得到相应钢种杨氏模量与温度的关系曲线;对于连铸而言,凝固过程中的粘滞性温度和固态组织类型决定了热膨胀系数的大小,65Mn钢凝固过程中直接生成γ奥氏体,因此热膨胀系数的峰值较SS400钢要大,达到0.000 36/℃。
In this research,based on the microscopic theory of solute segregation,and with the combination of the experimental test and calculation analyses,the high temperature thermodynamic properties of SS400 steel and 65 Mn steel for casting condition had been researched.It is shown that,the equivalent thermal conductivity,the equivalent specific heat and the Poisson's ratio are decided by the width of the corresponding solidification two-phase zone;the Young's modulus of the casting steel can be fitted by the high temperature tensile test results;the coefficient of thermal expansion is decided by the liquid impenetrable temperature and the metal tissue types,for 65 Mn steel,when solidifying,it forms γ-austenite directly,so its maximum coefficient of thermal expansion is bigger than SS400 steel,and reached 0.000 36/℃.
引文
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