Journal of Alloys and Compounds 509 (2011) 9938–9945 Contents lists available at ScienceDirect Journal of Alloys and Compounds j our na l ho me p ag e: www.elsevier.com/locate/jallcom Al/Ni metal intermetallic composite produced by accumulative roll bonding and reaction annealing A. Mozaffari, M. Hosseini, H. Danesh Manesh ∗ Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran a r t i c l e i n f o Article history: Received 1 February 2011 Received in revised form 27 July 2011 Accepted 30 July 2011 Available online 4 August 2011 Keywords: Metal-intermetallic composite Accumulative roll bonding process Mechanical properties a b s t r a c t In this research, Al/Ni multilayers composites were produced by accumulative roll bonding and then annealed at different temperatures and durations. The structure and mechanical properties of the fabri- cated metal intermetallic composites (MICs) were investigated. Scanning electron microscopy and X-ray diffraction analyses were used to evaluate the structure and composition of the composite. The Al 3 Ni intermetallic phase is formed in the Al/Ni interface of the samples annealed at 300 and 400 ◦ C. When the temperature increased to 500 ◦ C, the Al 3 Ni 2 phase was formed in the composite structure and grew, while the Al 3 Ni and Al phases were simultaneously dissociated. At these conditions, the strength of MIC reached the highest content and was enhanced by increasing time. At 600 ◦ C, the AlNi phase was formed and the mechanical properties of MIC were intensively degraded due to the formation of structural porosities. © 2011 Elsevier B.V. All rights reserved. 1. Introduction Aluminum intermetallic compounds are being studied as a structural material for special applications which demand light weight, high thermal stability, corrosion resistance, and good mechanical properties at high temperature [1–4]. Among various intermetallic compounds, Al–Ni based intermetallic compounds seem to be suitable for practical applications in the transporta- tion, aerospace, and similar industries [5]. However, the intrinsic low ductility and low fracture toughness at room temperature confine their application in engineering designs. A main method to compensate the brittleness of intermetallic compounds is the embedding of the intermetallic phases in the ductile matrix mate- rials in the form of particles or laminates [2]. Hereon, when a crack propagates inside the intermetallic phase and reaches the ductile metallic phase, owing to plastic deformation at the crack tip, the crack is blinded. Thus, the useful properties can practically be uti- lized in a structural material and the ductility of matrix material could avoid its brittle deficiency. It has been reported that Al/Ni metal intermetallic composites (MICs) have proper properties, such as high strength, resistance against fatigue and creep, good ductility and toughness, corrosion resistance and so on [6–8]. These properties make them suitable for some application, for instance aerospace, transportation and med- ical. Different methods have been used to produce MICs, including vacuum hot pressing, physical vapor deposition, magnetron ∗ Corresponding author. Tel.: +98 711 230 7293; fax: +98 711 230 7293. E-mail address: daneshma@shirazu.ac.ir (H.D. Manesh). sputtering, direct solidification and so on [3]. Generally, the pro- duction methods of MICs directly affect the shape and distribution state of intermetallic phases. Each technique has some specific advantages and disadvantages [3]. Most of them need expen- sive equipments and complex processes, which limits their usage at commercial and industrial scales. Dimensional limitations and time-consuming fabrication are other main problems for these methods. Accumulative roll-bonding (ARB) is a severe plastic deformation process to produce nanostructered materials by introducing struc- tural defects such as dislocations inside the material [9]. ARB is the only severe plastic deformation process applicable to produce con- tinuous bulky materials [10]. Rolling in the ARB process is not solely a deformation process but is a bonding process that could lead to a single-body solid material. The ARB process is also applicable in the fabrication of foams and various types of metal matrix composites [11–15]. Recently, the ARB process and subsequent annealing reac- tions have been used as a new production method of MICs [16,17]. In this technique, complex heat and chemical treatments, such as heat treatment at controlled environment, are not required [18]. Also, simplicity, no dimensional limitations and cheaper primary commodity are the other major advantages of the ARB process for the production of MICs. To the best of our knowledge, no evaluation has been conducted on the production of Al/Ni MIC by the ARB process. It would be worth mentioning that compared with low-formable Ti alloys usu- ally used for the same applications, this work aims to employ a general forming process (rolling) to fabricate Al/Ni MICs. In this research, initially Al/Ni metallic composites were fabri- cated by six ARB cycles of Al and Ni foils. Afterward, the composites 0925-8388/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.jallcom.2011.07.103