Study on Plastic Strengthening Mechanisms of Aluminum Matrix Nano-Composites Reinforced by Nickel Coated CNTs. Issue 10 (3rd October 2021)

• Record Type: Journal Article
• Authors: Song, Shutao; Billah, Muktadir; Zhou, Qiang; Ren, Luyang; Zheng, Liangfu; Chen, Quanfang; Bai, Yuanli
• Is Part Of: Composite interfaces. Volume 28:Issue 10(2021)
• Page Start: 1015
• Page End: 1036
• Publication Date: 2021-10-03
• Subjects: Al/NiCNT nano-composites -- strengthening mechanism -- RVE method -- plasticity -- interface; Composite materials -- Periodicals; 620.11805
• DOI: 10.1080/09276440.2020.1844528
• Languages: English
• ISSNs: 0927-6440

Abstract

ABSTRACT: The mechanical strength of pure aluminum matrix can be greatly enhanced by adding a small amount of nickel-coated carbon nanotubes (NiCNTs), where the nickel coating helps to the uniform dispersion of carbon nanotubes (CNTs) within the aluminum matrix through decreasing density difference and avoiding CNTs agglomeration. The yield strength of pure aluminum can be increased by 33.3% with 1% weight fraction of NiCNTs. This strengthening effect is caused by three mechanisms: Orowan looping, load bearing, and thermal expansion mismatch which are studied by both finite-element method and analytical method. A series of finite-element analyses using a representative volume element (RVE) method are conducted considering influences of CNTs aspect ratios, volume fraction of hardened zone, and the hardened plastic strain of hardened zone. The results show that the aspect ratio of CNTs is very important in the strengthening of CNT-reinforced composites, and the yield stress increases with increasing aspect ratio. A set of parameters for analytical solutions are optimized that can well describe and accurately predict the experimental data. Both the finite-element analysis and analytical solution are well correlated with the experimental results for Al/NiCNT composites with different weight fractions of CNTs. Graphical Abstract: uf0001