Modified utilization of semi-sectioned tubes as filler coated with MWCNTs–TiO2 in TIG arc welding to recover fusion lost mechanical properties of the weldment

Abstract

The loss of mechanical properties in heat treatable aluminum alloys categories during arc fusion welding processes is a critical issue, which limits the direct application in contrast to different post-treatments methods. This work involved a strategy for the novel and distinctive formation of fillers using 3-mm-diameter (AA6061) tubes having MWCNTs and TiO 2 nanoparticles coating on the inner surface. A series of experiments were conducted using TIG welding to evaluate the effect of welding current and composition of inside coating (MWCNTs-TiO 2) contents on welding strength. Three gradually increasing current values (160 A, 180 A and 200 A) were selected and tested against three combinations of nanocomposite coatings that include 1 wt% MWCNTs-TiO 2 , 1.5 wt% MWCNTs-TiO 2 and 2 wt% MWCNTs-TiO 2. Acceptable qualified bonding between nanocomposite and inside surface is utmost important before conducting the experiments, Tape Test (ASTM-D3359-09 e2) was performed for the assessment of bonding conditions and led to qualitatively exceptional bonding conditions after applying vacuum heating cycle. Tensile test results have demonstrated a significant improvement of 34.20-45.65% strength using innovative nanocomposite coated semi-sectioned tube in comparison to tube fillers without coating. Meanwhile, a beneficial gradually forming W-shape microhardness profile in contrast to conventional U and V shape profiles was achieved at 1.5 and 2 wt% of MWCNTs, and the uplift of hardness in the WZ region up to 86.51% subjected to increase high MWCNTs contents in combination with the current. Therefore, it is concluded to be a virtuous strategy for reinforcing mechanism of weldments to encounter some fusion property loss in aluminum alloys.

Effects of filler on the microstructure and corrosion of similar and dissimilar gas inert tungsten arc welding aluminum alloys joints

“…However, the welded Al alloys strength and corrosion resistance can improved by controlling the size and distribution of intermetallics, such as Mg 2 Si, Al 6 Mn, and Al 6 (Mn, Fe) 10 , 11 . Recent research has shown that incorporating nanomaterials, such as CNTs, TiO 2 , and Al 2 O 3 , in GTAW welding of Al alloys can improve the microstructure and mechanical properties while reducing welding defects 12 , 13 . Kumar.…”

Modified TIG Welding Joint Process: An Approach to Improve Microstructure and Fracto-Mechanical Behavior by MWCNTs Inducement in Al-Mg-Si Alloy

“…The process of filler fabrication was performed in two steps. The first step involved the utilization of MWCNTs (diameter 30 nm, length 20 µm) and TiO 2 (40–50 nm) as the precursor materials for the production of homogenized suspension [25]. Starting with MWCNTs and TiO 2 powder that were milled at low speed (250 RPM) to break-down the agglomeration and for achieving the uniform dispersion.…”

Wear Behavior Assessment of New Wire-Arc Additively Manufactured Surfaces on AA6061 and AA5086 Alloys through Multi-Walled Carbon Nanotubes and Ni Particles Inducement

“…Multiple types of single and multicomponent nanomaterial inducements are reported in the above discussion to improve surface properties after processing through LSA, MMC through stir casting, SPS, and WAAM techniques. In recent years, carbon-based nanomaterials, including multi-walled carbon nanotubes (MWCNTs) and graphene, have been considered as novel reinforcements for aluminum alloys for different arcs [27] and solidstate processing owing to their extraordinary properties such as tensile strength, Young's modulus, and ultra-low density. MWCNTs are described as a super-reinforced material for lightweight alloys as they support interfacial reaction, have a multi-walled physical appearance, and have considerable load-bearing competency along with restricting the dislocation movement within the lattice [28].…”