摘要
为解决超细晶材料强度高但延展性低的问题,设计了独特的挤压刀具及挤出通道,使材料在挤压、摩擦和切削的耦合作用下,一步制备厚度可控的双层梯度结构超细晶带材。采用数值模拟与试验相结合的方法对双层梯度结构纯铜带材的成形过程进行分析与研究,探索了挤压-切削加工机理以及工艺参数对双层梯度微结构的影响规律。研究结果表明,相比于原纯铜试样,挤压-切削制备的双层梯度结构纯铜带材的最大硬度约提高了三倍,同时带材也表现出优异的强度-延展性协同作用,即在牺牲部分延伸率情况下,屈服强度接近翻倍,极限抗拉强度则实现了四倍增长。
To address the issues of high strength but low ductility in ultrafine-grained materials,a unique squeeze tool and extrusion channel design was developed.This design enabled the one-step fabrication of ultrafine-grained sheets with a controllable thickness and a bilateral gradient structure through the combined effects of squeeze,friction and cutting.The numerical simulation and experimental methods were combined to analyze the forming processes of bilateral gradient structured pure copper sheets.The mechanism of squeeze-machining machining and the influences of processing parameters on the formations of the bilateral gradient microstructure were explored.The results show that,compared to the original pure copper samples,the maximum hardness of the pure copper sheets prepared using the squeeze-cutting method is increased by approximately threefold.Additionally,the sheets exhibit an excellent strength-ductility synergy:while some ductility is sacrificed,the yield strength nearly is of doubles,and the ultimate tensile strength0x0E䥺Symbol`@@0x0F increases by a factor of four.
作者
庞学勤
赵俊宇
邓文君
曾俞宁
钟佩璇
PANG Xueqin;ZHAO Junyu;DENG Wenjun;ZENG Yuning;ZHONG Peixuan(Faculty of Electrical and Mechanical Engineering,Kunming University of Science and Technology,Kunming,650500;School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou,510641)
出处
《中国机械工程》
北大核心
2025年第4期732-742,共11页
China Mechanical Engineering
基金
国家自然科学基金(52075187)
云南省基础研究计划(202301BE070001-021,202401CF070145)。
关键词
挤压-切削
可控厚度
双层梯度结构
梯度超细晶带材
机械性能
squeeze-machining
controllable thickness
bilateral gradient structure
gradient ultra-fine-grained sheet
mechanical property
作者简介
庞学勤,男,1991年生,博士、讲师。研究方向为金属切削加工、塑性成形加工与制造。E-mail:pangxq@kust.edu.cn;通信作者:钟佩璇,男,1995年生,博士后研究人员。研究方向为金属切削机理、大应变成形制造。E-mail:202121001913@mail.scut.edu.cn。