Mg-based Amorphous Vacuum Brazing The Magnesium Alloy Of AZ31B

Magnesium alloy is considered to be the most promising materials for energysaving and emission reduction development instead of traditional steel and titaniumalloys with abundant reserves, low density, strength-to-weight ratio and lowprice,etal. Due to magnesium alloy is more actively, the traditional tungsten argonarc welding, friction stir welding and electron beam welding etal can easily result inmagnesium alloy to react with the air without proper protection, causing defectsinclusions, pores and cracks. To solve the aforementioned problem, vacuum brazingwelding of magnesium alloy have been used in recent years. However, due to thefiller with high temperature will cause the material properties deterioration afterbrazing. Aiming at this problem, this paper use of magnesium based amorphousbrazing filler metals(Mg65Cu25Gd10)brazed magnesium alloy(AZ31B) and researchthe properties of brazing. Details are as follows:(1) The material selection of object. Because the main purpose of this paper is toreduce the brazing temperature and keep the weld microstructure uniformity, somagnesium based amorphous brazing filler metals (Mg65Cu25Gd10) have beenchoiced, the selected filler has the following characteristics: uniform components,low melting point (427℃) and good wettability characteristics.(2) The brazing techniquce. Through DSC analysis can determined amorphousbrazing filler metal melting point is427℃, according to the temperature thewelding technique have been confiremed as following:430℃,440℃and450℃keeping warm30min and40min in vacuum, respectively.(3) Microstructure and mechanical properties analysis. In this paper, using opticalmicroscope, scanning electron microscope, XRD and Vivtorinox hardness testeranalysis brazing weld microstructure, element diffusion effect, compound phasecomposition and the weld-base material hardness, respectively. The comprehensiveproperties of amorphous alloys Mg65Cu25Gd10welding of AZ31B magnesium alloyhave been analysed in this experiment. Through the above research, using amorphous alloy Mg65Cu25Gd10braze A-Z31B magnesium alloy at450℃, keeping warm40min. The welding jiont exhibitsgood metallurgical combination, At the same time, the weld metal compounds decre-ased comparing with low temperature and the welding line and base metal to maint-ain the same level of hardness, Last and foremost, the brazing technique in the paperwill not casued the deteriorated the base metal.