Hot deformation behavior and microstructure evolution of carbon nanotube/7055Al composite

被引：23

作者：

Ma, K. ^{[1
,2
]}

Liu, Z. Y. ^{[1
]}

Zhang, X. X. ^{[1
]}

Xiao, B. L. ^{[1
]}

Ma, Z. Y. ^{[1
,3
]}

机构：

[1] Chinese Acad Sci, Shichangxu Innovat Ctr Adv Mat, Inst Met Res, 72 Wenhua Rd, Shenyang 110016, Peoples R China

[2] Univ Sci & Technol China, Sch Mat Sci & Engn, 72 Wenhua Rd, Shenyang 110016, Peoples R China

[3] Guilin Univ Technol, Key Lab New Proc Technol Nonferrous Met & Mat, Minist Educ, Guilin 541004, Peoples R China

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2021年 / 854卷

基金：

国家重点研发计划; 中国国家自然科学基金;

关键词：

Carbon nanotube; Aluminum matrix composite; Hot deformation; Abnormal grain growth;

D O I：

10.1016/j.jallcom.2020.157275

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In this study, carbon nanotube (CNT) reinforced 7055Al composite was fabricated by high energy ball milling combined with powder metallurgy. The as hot-pressed composite had an inhomogeneous microstructure composed of coarse grains without CNTs and fine grains with uniformly dispersed CNTs. Processing maps were established and the hot deformation behavior as well as the microstructure evolution during deformation was investigated. It was indicated that the power dissipation efficiency of the composite was relatively lower at higher deformation temperature or lower strain rate. Abnormal grain growth (AGG) and cracking occurred when the composite was deformed at high temperature with low strain rate. A few of CNTs were embedded into coarse grains as AGG occurred, and the micro-cracks formed at the boundaries between the coarse and the fine grained zones. The cracking mechanism was considered as the stress concentration caused by the dragging effect of CNTs, and the reduced critical stress required for pore nucleation due to AGG at the boundaries between the coarse and the fine grained zones. (C) 2020 Elsevier B.V. All rights reserved.

引用

页数：10

共 38 条

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