摘要
The work is carried out to determine an optimal method to obtain the welded bimetallic joints of monolithic Mg-alloy with porous Al-alloy using gallium as chemical activator and heating up to 300 ℃ by two different methods:long-term in vacuum oven and short-term without vacuum by passing of low voltage current.There is no microstructure change in Al-foam but indentation test records the negligible reduction of the mechanical properties.SEM showed the crystallization of two types of Mg_(5)Ga_(2) and Mg_(2)Ga inter-metallic phases in the wavy uneven diffusion zone on Mg-alloy side with significant increase of micro-hardness and Young’s modulus.The narrow depth of the diffusion zone takes place in joints by short-term heating,so this method is more applicable for welding of monolithic and porous alloys at chemical activation using gallium.
基金
The work is part of Program《Research and development of arc welding and solid-state welding technologies for airspace,on-ground and floating high-speed vehicles》of National Academy of Sciences of Ukraine(Program No.1.6.1.1.7.3.(7/3))(2012–2016)
R&D Project(No.1.6.1.1.7.6.(7/6-П))for young scientist of Paton Welding Institute of NASU(2014–2015)。
