Characterization of friction stir welded boron carbide particulate reinforced AA6061 aluminum alloy stir cast composite

• Published in: Materials in engineering 2014-03, Vol.55, p.176-182
• Main Authors: Kalaiselvan, K., Dinaharan, I., Murugan, N.
• Format: Article
• Language: English
• Subjects: A. Non-ferrous metals and alloys; D. Welding; E. Mechanical properties; F. Microstructure
• ISSN: 0261-3069
• DOI: 10.1016/j.matdes.2013.09.067

[Display omitted] •Application of FSW to join AA6061/B4C stir cast composite.•Homogenous distribution of B4C particles in the weld zone.•Clusters in the parent composite are fragmented by the stirring action of the tool.•Hardening of weld zone.•FSW changed the fracture mode from ductile to brittle. Development of welding procedures to join aluminum matrix composite (AMCs) holds the key to replace conventional aluminum alloys in many applications. In this research work, AA6061/B4C AMC was produced using stir casting route with the aid of K2TiF6 flux. Plates of 6mm thickness were prepared from the castings and successfully butt joined using friction stir welding (FSW). The FSW was carried out using a tool rotational speed of 1000rpm, welding speed of 80mm/min and axial force of 10kN. A tool made of high carbon high chromium steel with square pin profile was used. The microstructure of the welded joint was characterized using optical and scanning electron microscopy. The welded joint showed the presence of four zones typically observed in FSW of aluminum alloys. The weld zone showed fine grains and homogeneous distribution of B4C particles. A joint efficiency of 93.4% was realized under the experimental conditions. But, FSW reduced the ductility of the composite.