Impact behaviour of A356 alloy for low-pressure die casting automotive wheels |
| |
| Authors: | Mattia Merlin Giulio Timelli Franco Bonollo Gian Luca Garagnani |
| |
| Affiliation: | 1. Department of Engineering, University of Ferrara, Via Saragat 1, I-44100 Ferrara, Italy;2. Department of Management and Engineering, University of Padova, Stradella S. Nicola 3, I-36100 Vicenza, Italy;1. Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, PR China;2. Laboratory of Special Processing of Raw Materials, Dalian University of Technology, Dalian 116024, PR China;1. Materials Science and Technology Division, CSIR – National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala, India;2. Department of Metallurgical and Materials Engineering, National Institute of Technology, Surathkal, Karnataka, India;3. Computational Modeling & Simulation, Environmental Technology Division, CSIR – National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, Kerala, India;1. Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036, India;2. Department of Physics and Nanotechnology, SRM University, Chennai 603203, India;3. College of Engineering and Design, Alliance University, Bengaluru 562106, India |
| |
| Abstract: | Instrumented impact strength tests have been carried out on KV sub-size Charpy samples drawn from A356 aluminium alloy 17-in. wheels, produced by a low-pressure die casting. The wheels show different geometry and thermal treatment. In this paper, the effects of microstructure and defects on the impact properties are studied. The results indicate that the impact energy is lower in as-cast wheel than in T6 heat-treated wheels. A finer microstructure always corresponds to higher impact strength, while a direct correlation between the resistance to crack propagation values and secondary dendrite arm spacing (SDAS) exists. Casting defects, revealed by means of X-ray and density measurements techniques, become critical when concentrated around the V-notch, where they reduce the load bearing area of Charpy specimens. The fracture profile and surface of Charpy specimens have been investigated revealing how the crack crosses the interdendritic eutectic region where a significant fraction of cracked eutectic silicon and intermetallic particles is found.Numerical simulations have been performed to study the filling and solidification behaviour of the alloy of the wheels analysed, in order to predict the final microstructure and shrinkage formation. Solidification times, estimated by means of SDAS measurements and calculated with a numerical simulation approach, show a good correspondence. Critical areas, as concern hot spots and shrinkage porosities, are generally revealed in the zone of the wheels between the spoke and the rim, as well as in the rim area. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
