摘要
等通道转角挤压应变计算为掌握挤压变形程度、衡量强烈变形效果、正确制定工艺规程、合理设计成形模具提供重要依据。目前国内外强烈塑性变形领域广泛使用Iwahashi Y于1996年提出的应变计算公式。经过分析,指出了该计算公式理论推导不严谨,关于切向速度间断对变形影响的分析有误,对运算过程中的近似处理不当,应变计算结果不正确,未能反映挤压变形的真实情况。根据强烈塑性变形特点,分析了挤压塑性变形区的流动规律,针对该公式存在的问题采取了改进措施,经过详细运算,建立了概念比较完整、理论比较严谨的新公式,并结合实例对两者进行了比较。实例计算结果证明了提出的新应变计算公式的有效性。
The strain calculation for equal-channel angular extrusion provides the basis data to grasp the deformation degree,to measure effect of the severe plastic deformation,to formulate the technical regulation and to design the forming die. In the field of severe plastic deformation at home and abroad,the widely adopted formula for strain calculation was put forward by Iwahashi Y in 1996 is widely adopted. However,after analysis,faults about this formula were pointed out： analyses of the effect of tangential velocity discontinuity on deformation is not correct and the operation of approximate is mishandled,thus the strain calculation is not correct and fails to reflect the real situation of extrusion deformation. Based on characteristics of severe plastic deformation,the flow law of metal particle in plastic deformation zone was analyzed. After detailed operation,a new formula with more completive concept and more rigorous theory for strain calculation was established,and the two formulas were compared combining with a practical sample. The result proves the effectiveness of the new established formula.
作者
罗文波
彭炎荣
罗嘉维
LUO Wen-bo PENG Yan-rong LUO Jia-wei(Civil Engineering and Mechanics College, Xiangtan University, Xiangtan 411105, China Mechanical Engineering College, Xiangtan University, Xiangtan 411105, China Mechanical and Vehicle Engineering College, Hunan University, Changsha 410082, China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2017年第5期141-146,共6页
Journal of Plasticity Engineering
基金
国家自然科学基金资助项目(11572275)
关键词
等通道转角挤压
等效应变
强烈塑性变形
切向速度间断
equal-channel angular extrusion
equivalent strain
severe plastic deformation
discontinuity of tangential speed
