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使用NETZSCH DIL 402C热膨胀仪与STA449F3综合热分析仪，对304不锈钢的高温膨胀与收缩系数、定压热容（cp ）及差示扫描量热（DSC）曲线进行测试。测试结果表明：304不锈钢在升温过程中膨胀系数的范围为20．9700×10-6～21．5712×10-6K-1，降温过程中收缩系数范围为21．2528×10-6～21．9471×10-6K-1，膨胀及收缩系数较大，属裂纹敏感性钢种；在900～1400℃升温过程中，定压热容曲线波动幅度较大，存在晶型转变，铸坯稳定性较差，易产生缺陷；DSC 曲线测试中，升温过程在1420．8℃存在明显吸热峰，试样开始熔化，峰值温度为1438．86℃；降温过程中，1439℃时存在明显的放热峰，试样开始凝固，峰值温度为1435．6℃。在1439～1100℃降温过程中，曲线不平滑，热稳定性较差，有相变发生，初始坯壳生长不均匀，这些温度点属于结晶器中上部温度范围，此范围内铸坯易产生裂纹。

The DIL402C thermal dilatometer and STA449C thermal analyzer were employed to test the linear expan-sion and contraction coefficient,specific heat cp and DSC curve of 304 stainless steel.The result shows that the range of linear expansion coefficient was 20.9700×10-6~21.5712×10-6K-1 during heating and the range of linear con-traction coefficient was 21.2528×10-6~21.9471×10-6K-1 during cooling.The linear expansion and contraction coefficient were higher than other materials,so the 304 stainless steel belong to the crack sensitive steel.The curve of cp oscillates obviously during the 900~1 400℃ as temperature raise.Because of the transformation of crystalline shape occurs,the defects of casting blank occur easily.A endothermic peak exists obviously at 1 420.8℃ during the DSC test.The sample began to melt at 1 420.8℃and the peak temperature was 1 438.86℃in the heating step.The sample began to solidify at 1 439℃ and the peak temperature was 1 435.6℃ in the cooling step.During the 1 439~1 100℃ as temperature fell,the curve of DSC was unsmooth,the thermostability was bad and phase change occurs. These factors cause the initial solidified shell non-homogeneous.These temperature points belong to the upper of crystallizer,so the casting blank causes crackle easily during this temperature range.