Shear punch test in Al/Alumina composite strips produced by powder metallurgy and accumulative roll bonding Majed Zabihi, Mohammad Reza Toroghinejad n , Ali Shafyei Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156–83111, Iran article info Article history: Received 11 January 2016 Received in revised form 23 April 2016 Accepted 28 April 2016 Available online 5 May 2016 Keywords: Powder metallurgy Accumulative roll bonding Shear punch test Alumina reinforcement Mechanical properties Shear failure surface abstract Al-0.2, 0.4, and 0.8 wt% alumina composites were manufactured via powder metallurgy and hot rolling techniques successfully followed by the accumulative roll bonding (ARB) process. Microstructural char- acterization of the composite strips thus fabricated was carried out using optical and scanning electron microscopy. The shear punch test (SPT) and Brinell hardness measurements were used to investigate the mechanical properties of the ARB-ed samples, which revealed that alumina powder particles became more uniformly distributed with increasing number of ARB cycles. Regarding porosity, no pores could be detected among the Al and alumina particles after the fifth ARB cycle. The results also indicated that shear elongation percentage of the specimens decreased before it gradually increased with increasing number of ARB cycles while their shear strength and hardness improved. Another finding of the present study was that the shear failure surfaces of the hot rolled strips ex- hibited a ductile fracture with a dimple structure while those processed by the ARB technique demon- strated shear flattened surfaces. & 2016 Elsevier B.V. All rights reserved. 1. Introduction Aluminum matrix composites are those in which aluminum is reinforced with ceramic particles in the micron range such as Al 2 O 3 , TiC and SiC. The composites have found extensive applica- tions in the aerospace industry due to their light weight and af- fordable manufacturing costs [1,2]. Moreover, they offer great potentials for high temperature and wear resistance applications because of their excellent mechanical and physical properties [3– 5]. Their applications in the automotive industry include bearing surfaces, cylinder liners, rockers, and brake components [6]. Different procedures may be employed for the fabrication of aluminum/Al 2 O 3 composites; these include powder metallurgy (PM) [7–9], squeeze casting, stir and compo-casting [10,11], ARB [3, 12–15], and the anodizing-ARB process [16]. The ARB process is one of the effective severe plastic deformation (SPD) routes, de- veloped by Saito et al. [17], which can be used to produce ultra- fine-grained metallic materials. Its important advantages over the SPD procedures include: 1) Low die-making costs and lack of need for high forming machines, 2) continuity of the process and high productivity, and therefore, 3) unlimited amount of material that it can produce [18,19]. SPT is a miniature testing method which has been used for evaluating the mechanical behavior of composites [20], weldment materials [21], porous materials [22], and nuclear irradiated ma- terials [23]. Al/alumina composite strips have also been fabricated via the vacuum hot pressing technique and the hot rolling process and the mechanical behavior of the strips have been evaluated using SPT [1,24]. In the present study, high strength and highly uniform Al/alu- mina composite strips are manufactured via PM, hot rolling, and ARB processes. Moreover, the microstructural evolution and shear punch test behavior of the strips thus produced are investigated after the ARB process. 2. Materials and experimental details 2.1. Sample preparation As-received commercial aluminum powder (with a purity of  93.8% and a particle size of o40 μm) and alumina powder particles (with a particle size of 3–8 μm and polyhedral in shape) were used as the matrix and reinforcement materials, respectively. The chemical composition of the aluminum powder is reported in Table 1. The specifications of the alumina powder particles are presented in Table 2. The aluminum powder was mixed with 0.2, 0.4, and 0.8 wt% alumina in a high energy planetary ball mill Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/msea Materials Science & Engineering A http://dx.doi.org/10.1016/j.msea.2016.04.097 0921-5093/& 2016 Elsevier B.V. All rights reserved. n Corresponding author. E-mail addresses: m.zabihi@ma.iut.ac.ir (M. Zabihi), toroghi@cc.iut.ac.ir (M.R. Toroghinejad), shafyei@cc.iut.ac.ir (A. Shafyei). Materials Science & Engineering A 667 (2016) 383–390