Reinforcement Behavior in Laser Welding of A356/TiB_2p MMCs

Abstract

TiB_2p behavior was systematically studied in laser welding of A356/TiB_2p metal matrix composites (MMCs). TiB₂ particles encountered three different types of evolution under the direct irradiation of laser, including oxidization, escaping out of the bead and immigration in the welding pool. TiB₂ particles remained solid state in the welding pool. The clusters of solid TiB₂ particles were pushed into smaller clusters size and dispersive TiB₂ particles by the outflow of Al plasma. After solidification, the distribution of TiB₂ in the bead got more homogeneous than pre-welding. TiB₂ and Al matrix bonded in strong semi-coherent relationship.