Research on weldability of ZL101/TiB2 MMCs by laser-TIG hybrid welding

The weldability of in situ TiB 2 reinforced ZL101 metal matrix composites (MMCs) was examined using laser-TIG hybrid welding technology. High speed camera was employed to observe the coupled results between laser plume and electric arc. Optical microscope (OM), scanning electron microscope (SEM), tensile machine and wearing equipment were used to evaluate the quality of welding joint. The effective hybrid welding was realized and defect-free seam was obtained when the laser power (8 kW), TIG current (100 A) and welding speed (3 m/min) were combined. TiB 2 distribution became much more homogeneous than the pre-welded, and microstructure of seam was finer obviously. Tensile and wear resistance test showed that the weld seam presented higher strength and better wear-resistance properties than the base metal. The results indicated that TiB 2 reinforced aluminum matrix composites were successfully welded using the laser-TIG hybrid welding method. © 2012 Editorial Board of CHINA WELDING.