In this research, the size effect in the micro-upsetting process of oxygen-free high conductivity copper has been investigated numerically and experimentally. For the numerical part of this study, the crystal plasticity finite element (CPFE) method was employed and grains were produced using the Voronoi algorithm. The homogenization method was used for curve fitting and to obtain the material-hardening parameters. Then, simulation of the micro-upsetting process was carried out using a VUMAT subroutine which was written to implement crystal plasticity formulation. The micro-upsetting process was carried out at compression deformation of 50% for parts with diameters 0.75, 1 and 2 mm and height ratio of 1.5. Comparison of the data obtained from the CPFE and experimental procedures indicated a remarkable agreement. The results showed that, by increasing grain size from 30 to 60 μ m, the forming forces for the diameters 0.75, 1 and 2 mm reduce by 12.3%, 6.8% and 6.7%, respectiv...

中文翻译：

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OFHC铜的微塑性过程的结晶塑性有限元模拟与实验研究

在这项研究中，通过数值和实验研究了无氧高电导率铜的微-粗工艺中的尺寸效应。对于本研究的数值部分，采用了晶体可塑性有限元（CPFE）方法，并使用Voronoi算法生成了晶粒。均质化方法用于曲线拟合并获得材料硬化参数。然后，使用VUMAT子例程进行微-粗过程的仿真，该子例程被编写为实现晶体可塑性配方。对于直径为0.75、1和2 mm，高度比为1.5的零件，在50％的压缩变形下执行微-锻工艺。从CPFE和实验程序获得的数据的比较表明了惊人的一致性。结果表明，