Original Research Paper Experimental investigation and FE simulation of nano-indentation on Al–Al 2 O 3 nanocomposites A. Wagih ⇑ , A. Fathy Mechanical Design and Production Dept., Faculty of Engineering, Zagazig University, P.O. Box 44519, Zagazig, Sharkia, Egypt article info Article history: Received 22 March 2015 Received in revised form 18 January 2016 Accepted 20 January 2016 Available online xxxx Keywords: Finite element simulation Nano-indentation experiment Hardness Nanocomposite abstract The main purpose of this paper is to investigate the nano-indentation test method and validation of its finite element simulation (FE). In the first stage, a series of nano-indentation tests were performed on the Al–Al 2 O 3 nanocomposites by using Triboscope system and Berkovich indenter to obtain its hardness. To prepare the Al–Al 2 O 3 nanocomposites, a pre-alloyed powder was milled in a planetary ball mill followed by cold compaction and sintering. Then in the second stage, the nano-indentation process on Al–Al 2 O 3 nanocomposites was simulated by a 2D axisymmetric finite element (FE) model. Using the same projected area to depth function as the standard Berkovich indenter, a conical indenter with half angle 70.3° was considered in simulations. The results showed that, a homogenous distribution of the nano- sized Al 2 O 3 particles in the Al matrix was achieved after 20 h milling. The young’s modulus, yield strength, and hardness of the produced nanocomposite were increased than the pure aluminum. The results of load–displacement curve obtained from the finite element simulation of non-sharp indenter showed a good agreement with that obtained from the nano-indentation experiment. The scatter of the FE results than the experimental results in the pure aluminum is smaller than that observed for the nanocomposite. Ó 2016 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. 1. Introduction In recent years, metal-matrix composites (MMCs) have replaced conventional materials for many structural and tribological com- ponents due to their superior mechanical properties, such as light weight, high stiffness and strength, and excellent wear and creep resistance. During the last two decades, a lot of research has been conducted on aluminum matrix composites (AMCs). An optimum combination of high strength and ductility gives aluminum based metal matrix composites (AMCs) a wide range of possible advanced applications. The most important AMCs applications in aerospace and infrastructure industries are enabled by functional properties including high structural efficiency, excellent wear resistance, and attractive thermal and electrical characteristics [1–5]. Powder metallurgy is considered as a good technique in produc- ing metal-matrix composites. An important advantage of this method is its low processing temperature compared to melting techniques. Therefore, interaction between the matrix and the reinforcement phases is prevented. On the other hand, good distribution of the reinforcing particles can be achieved. Another advantage of powder metallurgy technique is in its ability to man- ufacture near net shape product with low cost [6–10]. As a fair judge on this new material to decide the percentage of enhancement in the properties is to measure the mechanical prop- erties of the composites and compare it with the properties of the conversional materials. Different mechanical test methods are available to measure the mechanical properties of materials. Uniaxial tensile test is a conventional method for measuring the mechanical properties like Young’s modulus, yield strength, strain hardening, toughness and tensile strength. Conventional mechani- cal test methods are often destructive and need relatively large amount of sample materials. Recently, some researchers start to use the nano-indentation technique to measure the mechanical properties of both bulk materials and thin coatings [11–13]. Since in the nano-indentation test the indentation depth is in the order of nanometer and the residual indentation diameter is often in the order of nanometer, this test needs less sample material, decreases costs and is independent of the specimen geometry. In the last two decade, the use of finite element methods (FEM) for modeling different engineering problems was really increased. Indentation process was investigated using FEM by http://dx.doi.org/10.1016/j.apt.2016.01.021 0921-8831/Ó 2016 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved. ⇑ Corresponding author. Tel.: +20 34 617055836. E-mail addresses: ahmedwagih@zu.edu.eg, eng_awa2011@yahoo.com (A. Wagih), afmeselhy@zu.edu.eg (A. Fathy). Advanced Powder Technology xxx (2016) xxx–xxx Contents lists available at ScienceDirect Advanced Powder Technology journal homepage: www.elsevier.com/locate/apt Please cite this article in press as: A. Wagih, A. Fathy, Experimental investigation and FE simulation of nano-indentation on Al–Al 2 O 3 nanocomposites, Advanced Powder Technology (2016), http://dx.doi.org/10.1016/j.apt.2016.01.021