Effects of SiC on the Strengthening Activated Tungsten Inert Gas (SA-TIG) Welded of Magnesium Alloy

Abstract

The effects of SiC particles on the morphologies, microstructures, and mechanical properties of tungsten inert gas welded AZ31 magnesium alloy joints with TiO 2 flux coating were studied. The results showed that an increase in the amount of the TiO 2 coating improved the weld penetration and the depth/width (D/W) ratio of the TIG welded AZ31 magnesium alloy seams. The a-Mg grains of FZ of welded joints refined gradually with the addition of micro-sized SiC (<30%) =nano-sized SiC (<40%) particles in coatings, and then coarsened when more SiC particles added. In addition, the microhardness of the FZ and ultimate tensile strength of the welded joints increased with the addition of SiC particles, and nano-sized particles have more strong efficiency on the improvement of mechanical properties compared with micro-sized SiC particles.

Ciclo térmico y soldabilidad de las aleaciones de aluminio

“…Proceso de soldeo GTAW: El proceso de soldeo por arco eléctrico más utilizado en las aleaciones de aluminio es el proceso de soldeo GTAW donde se emplea un electrodo no consumible de tungsteno con protección de gas generalmente argón ó helio, siendo opcional la aportación del material (Arivazhagan y Vasudevan, 2013;Mougenot et al, 2013y Shen et al, 2013. El proceso de soldeo median te GTAW permite controlar la potencia aportada en el proceso, manteniendo la intensidad constante con voltaje variable de acuerdo a su curva característica, manteniendo la polaridad negativa en el electrodo (DCEN).…”

Effect of Polarity and Oxide Fluxes on Weld-bead Geometry in Activated Tungsten Inert Gas (A-TIG) Welding

“…in autogenous TIG welding was explored by several researchers 15,16) . Shen et al 17) found that a growth in the percentage of TiO 2 in a flux mix-ture can lead to better penetration with increased aspect ratio. Changes in surface tension gradient of liquid metal of the molten weld pool occur when activating flux is applied, that reverse Marangoni flow direction 18) and thus, hot metal beneath the arc flows downwards leading to enhanced penetration.…”

Effects of current on nanoparticle reinforced magnesium alloy welding joints

“…15,16 On this basis, Shen et al proposed a nano-SiC particle strengthening activating flux tungsten inert gas (NSA-TIG) welding technique, finding the strengthening effects of SiC particles was improved further by refining their size from micrometres to nanometres. 17,18 Up to now, limited research was conducted to systematically investigate the influence of welding parameters on the microstructures and mechanical properties of NSA-TIG welded magnesium alloy joints, especially the welding current. Therefore, in the present study, various welding currents were applied in the NSA-TIG welding tests of AZ31 magnesium alloy plates, and their effects were discussed in detail.…”

“…15, 16 On this basis, Shen et al proposed a nano-SiC particle strengthening activating flux tungsten inert gas (NSA-TIG) welding technique, finding the strengthening effects of SiC particles was improved further by refining their size from micrometres to nanometres. 17, 18…”