【作者】 施展； 李晓菲； 池天惠； 李卫彬； 卢勇； 杨水源； 王翠萍； 刘兴军；

【Author】 Shi Zhan;Li Xiaofei;Chi Tianhui;Li Weibin;Lu Yong;Yang Shuiyuan;Wang Cuiping;Liu Xingjun;College of Materials,School of Physics and Mechanical & Electrical Engineering,Xiamen University;Department of Aeronautics,School of Physics and Mechanical & Electrical Engineering,Xiamen University;

【机构】 厦门大学材料学院； 厦门大学物理机电学院航空系；

【摘要】 本文以最基本的Ni-Al二元合金作为模型合金,采用Thermo-Calc软件结合复合材料的有效介质理论对γ/γ′体系的热膨胀系数进行了理论模拟,研究了γ′的溶解与热膨胀系数之间的关系。结果表明:在γ′未发生溶解的低温度范围内,Ni-Alγ/γ′合金的热膨胀系数随γ′含量增加而降低,符合复合材料的混合定律。当温度超过500℃时,γ′逐渐开始溶解,中温区和高温区γ/γ′体系的热膨胀系数的增加与γ′相的溶解有直接的关系。因此,要得到低膨胀γ/γ′高温合金,应注意提高γ′相的热稳定性,尽可能使γ′相体积分数在服役温度附近保持稳定。更多还原

【Abstract】 In this paper,the relationship of the dissolving of γ’ phase and the thermal expansion coefficient(CTE) have been studied based on the basic Ni-Al alloys.A quantitatively simulation of the alloys’ thermal expansion behavior have been carried out using the effective mediumapproaeh and Thermal-Calc software,γ’ phasehave not been dissolved in low temperature range,the CTE decrease with the increasing of the content of γ’ phase in the Ni-Al γ/γ’ alloy.This is in agreement with the ’ mixture law’ for common composites.When the temperature is above 500℃,in the middle and higher temperature range,the γ’phase begins to dissolve,the increasing of the CTE in γ/γ’ is proved to result from the dissolving of the γ’ phase.Therefore,to achieve lower thermal expansion in γ/γ’ superalloys,it is necessary to improve the phase stability of γ’ phase in service temperature range.更多还原