Interface Shear Actions and Mechanical Properties of Nanostructured Dissimilar Al Alloy Laminated Metal Composites

Zejun Chen,Quanzhong Chen

doi:10.1155/2015/612029

Abstract

The laminated metal composites (LMCs) of dissimilar metals (aluminium alloys: AA1100/AA7075) were fabricated using the accumulative roll bonding technique in conjunction with cold rolling. The LMCs of ultrafine grained AA1100 and nanostructured precipitates of AA7075 achieved metallurgical bonding. The microstructure of the bonding interfaces and constituent metals was investigated using scanning electron microscopy and transmission electron microscopy for the LMCs with different layers. The deformation incompatibility and shear actions were analyzed using the microanalysis of dissimilar bonding interfaces. The mechanism of grain refinement of LMCs was investigated and described based on the microstructure characterization. The mechanical properties, strengthening mechanism, and fracture mechanism of LMCs were also investigated. The research results showed that the strengthening mechanism of LMCs is the recombination action of grain refinement, dislocation, and laminated interfacial strengthening. The coordinated deformation of dissimilar metals and the layer thickness are important in improving the mechanical properties of LMCs consisting of dissimilar metals.

Highlights

Ultrafine grained (UFG) materials include both submicrocrystalline materials with grain sizes in the range of 100– 1000 nm and nanocrystalline materials with grain sizes below 100 nm
The fluctuation of layer thickness starts with 20-layer laminated metal composites (LMCs) (Figure 4(b)), and the degree of fluctuation is enhanced with increasing numbers of layers below a certain layer number
This paper investigated the interface shear actions and mechanical properties of nanostructured Al alloy laminated metal composites (LMCs)

Summary

Introduction

Ultrafine grained (UFG) materials include both submicrocrystalline materials with grain sizes in the range of 100– 1000 nm and nanocrystalline materials with grain sizes below 100 nm. Such materials usually have superior mechanical and physical properties, including high strength, improved corrosion resistance, and higher wear resistance, which are very different from the same materials comprising conventionally sized grains [1,2,3,4,5]. The second is the “top-down” approach in which existing coarse grained materials are processed to produce ultrafine grains. The recrystallization of the material leads to finer and finer grain sizes and under

Objectives

Results

Conclusion