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为确定ＤＤ３单晶合金蠕变参数，进行了多个拉伸蠕变试验，试验温度为７６０℃、８５０℃和９５０℃，试验应力为２００ＭＰａ至 ８００ ＭＰａ，试样取向为［００１」和［１１１］晶体取向。试验结果表明，在 ８５０℃和 ９５０℃下蠕变应变率连续增加直至试样断裂，［００１］晶体取向的蠕变应变大于［１１１］晶体取向的蠕变应变。采用单纯形优化方法拟合了材料的蠕变参数，拟合参数表明，应力指数和时间指数分别为６～１１和０．３～１．４。最后根据晶体滑移本构模型给出了十二面体滑移系和六面体滑移系蠕变参数。
To determine the creep parameters of DD3 single crystal alloys, a number of tensile creep tests were carried out with test temperatures of 760 ° C, 850 ° C and 950 ° C, test stresses of 200 MPa to 800 MPa and sample orientations of [001] and [111 ] Crystal orientation. The experimental results show that creep strain rate increases continuously at 850 ℃ and 950 ℃ until the specimen breaks, and the creep strain of [001] crystal orientation is larger than the creep strain of [111] crystal orientation. The simplex method was used to fit the creep parameters of the material. The fitting parameters showed that the stress exponent and time index were 6 ~ 11 and 0.3 ~ 1.4, respectively. Finally, the creep parameters of dodecahedron and hexahedron slippage are given according to the crystal slip constitutive model.