摘要:
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使用上限定理得到了等径角挤压(ECAP)过程中圆柱试样的上限挤压力解析式,并对纯铜圆柱试样进行了等径角挤压实验及有限元仿真模拟,结合实验与有限元模拟对ECAP过程的上限挤压力解析式进行了两方面的验证,结果显示解析式计算值、仿真模拟值和实验值三者结果相近,表明解析式具有一定的准确性。另外,使用ABAQUS有限元软件对不同半径及不同长度的纯铜圆柱试样ECAP过程进行了有限元模拟分析,并结合理论解析式,讨论了试样半径及试样长度对上限挤压力大小的影响。结果表明,圆柱形试样的半径和长度与ECAP挤压力正相关。但是,对于半径大于4 mm的试样,有限元模拟结果比解析式计算值大,而且随着半径的增大,差值有增大的趋势。
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Analytical formula of upper bound extrusion force of the cylindrical specimen in process of equal channel angular pressing(ECAP) was obtained by the upper-bound theorem, and the equal channel angular extrusion test and finite element simulation of pure copper cylinder specimens were carried out. Then, the upper bound extrusion force formula of ECAP process was verified by experiments and finite element simulation. The results show that the calculated results of analytical formula, the simulation value and the experimental value are similar, which indicates that analytical formula has a certain accuracy. In addition, the ECAP process of pure copper cylindrical specimens with different radiuses and different lengths is simulated by finite element software ABAQUS, and the influences of specimen radius and sample length on the upper-bound extrusion force are discussed by combining with theoretical analytic formula. The results show that the radius and length of the cylindrical specimen are positively related to the ECAP extrusion force. But, for the specimen with radius greater than 4 mm, the finite element simulation results are larger than that of the analytical formula, and the difference increases with the increase of radius.
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基金项目:
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现代汽车零部件技术湖北省重点实验室开放基金资助项目(2013-06)
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作者简介:
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左治江(1974-),男,博士,教授
E-mail:dongfc2001@sohu.com
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参考文献:
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