混合实验法在W-Ni-Cu合金组分设计中的应用

采用极端顶点设计法设计W-Ni-Cu合金组分,将组分自变量与相对应的性能因变量(相对密度、显微硬度、抗弯强度)进行回归分析和规划求解,同时采用冷压烧结法制备不同组分的W-Ni-Cu合金,测定合金的密度、显微硬度和力学性能,研究组分对合金性能的影响。结果表明:回归方程复相关系数R~2=1,方程精确度高;合金性能随组分变化而呈规律变化;当Ni含量与Cu含量(均为质量分数)分别为3%和5%时,合金的综合力学性能最佳:相对密度为94.295%、显微硬度286.55、抗弯强度931.51 MPa。W-Ni-Cu合金的相对密度计算值与实验结果的误差为-0.45%~0.06%,显微硬度计算值与实验结果的误差为-8.48%~4.46%,抗弯强度计算值与实验结果的误差为-5.19%~4.15%。误差很小,说明混合实验和极端顶点设计法能优化W-Ni-Cu合金组分,并可靠预测合金性能。

Application of mixture experiments in the composition design of W-Ni-Cu alloys

The compositions of W-Ni-Cu alloys were designed via the extreme vertex design method. The composition as independent variable and their corresponding properties as dependent variable (such as relative density, micro-hardness, bending strength) were analyzed by using regression and the programming solver. The W-Ni-Cu alloys were prepared by cool isostatic pressing and sintering, and the effect of the composition on the properties of alloys was studied by testing the density, micro-hardness and mechanical properties. The results show that the multiple correlation coefficientR2 of the regression equation is about 1, and the properties of the alloys change regularly with the variation of compositions. When the mass fractions of Ni and Cu are 3% and 5%, respectively, the optimal mechanical properties with the relative density of 94.295%, the micro-hardness of 286.55 and the bend strength of 931.51 MPa are obtained. The relative density error value of the W-Ni-Cu alloys between calculated value and experimental value is about?0.45%?0.06%, and the micro-hardness error value and the bending strength error value are?8.48%?4.46% and 5.19%?4.15%, respectively. Therefore, the extreme vertex design method can be used to optimize the composition of W-Ni-Cu alloys, and predict the properties of the alloys.