Effect of nano-silver on microstructure, mechanical and tribological properties of cast 6061 aluminum alloy
(1. Department of Mechanical Engineering,
Sethu Institute Technology, Kariapatti, Virudhunagar 626 115, Tamilnadu, India;
2. Department of Mechanical Engineering, Rajalakshmi Institute of Technology, Chennai 600 124, Tamil Nadu, India;
3. Department of Mechanical Engineering, Kamaraj College of Engineering and Technology, Virudhunagar 626 001, Tamil Nadu, India)
Abstract: Al6061 matrix with different amounts of nano-silver (1% and 2%) was produced by stir-casting method. Produced samples were characterized by hardness, tensile, compression and wear tests. The hardness of the specimens at room temperature was measured by Brinnell hardness testing machine. The magnitude of hardness increased evidently with the function of the mass fraction of the nano-Ag particle. The polished specimens were examined with an optical microscope. The fracture surfaces of tensile and compressive specimens were further examined by scanning electron microscopy. Wear mechanisms were discussed based on the scanning electron microscopy observations of worn surface and wear debris morphology. There is an increase in compressive strength, ultimate tensile strength, elongation and wear resistance of the Al-Ag composites compared with base alloy. The execution of stir-casting technique is relatively homogenous and fine microstructure which improves the addition of reinforcement material in the molten metal. The results show that Al6061-nano-silver which is the best combination of hardness can replace the conventional material for better performance and longer life.
Key words: Al6061 alloy; nano silver; stir casting; mechanical properties; tribological properties