Investigation on microstructure and mechanical properties of Al/Cu butt joints by CMT method in asymmetrical V-groove configuration

2020 ◽  
Vol 117 (3) ◽  
pp. 303
Author(s):  
Gang Li ◽  
Jufeng Song ◽  
Xiaofeng Lu ◽  
Xiaolei Zhu ◽  
Shengyu Xu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Feed Rate ◽  
Pure Copper ◽  
Xrd Analysis ◽  
Fusion Welding ◽  
Al Alloy ◽  
Butt Joints ◽  
Cold Metal Transfer ◽  
Microstructure And Mechanical Properties ◽  
Wire Feed

It is a challenge work for joining of Al to Cu by conventional fusion welding method. This study investigates butt joining of 6061 Al alloy to pure copper using cold metal transfer (CMT) process in asymmetrical V-groove configuration. The microstructure and mechanical properties of Al/Cu butt joints are revealed. The microstructure in the fusion zone mainly consists of α (Al) and Al2Cu phase accompanied with Si phase. The two-layer intermetallic compound (IMC) layers are exhibited at the Al/Cu interface. The first IMC layer near the copper is a thin layer in thickness of less than 5 μm. The second IMC layer is in the irregular non-linear and zigzag shape with some particles dispersed at the boundaries. XRD analysis shows that the IMCs in the joints mainly contain Al2Cu, AlCu, Al3Cu4 and Al4Cu9 phase. The ultimate tensile strength (UTS) of the joints could reach 108 MPa. The fracture paths of the joints are along the Al/Cu interface. The pores and IMCs are main factors to determine the strength of the joints. Since the pores are at the Al/Cu interface, the UTS of the joint is lowered at low wire feed rate. The joints break along the Al/Cu interface due to the brittle IMC layer at high wire feed rate. It can be achieved Al/Cu butt joints with sufficient strength in asymmetrical V-groove configuration.

scholarly journals Friction Stir Welds of Al Alloy-Cu: An Investigation on Effect of Plunge Depth

2016 ◽  
Vol 63 (4) ◽  
pp. 619-634 ◽  
Author(s):  
Mohd Atif Wahid ◽  
Arshad Noor Siddiquee ◽  
Zahid Akhtar Khan ◽  
Mohammad Asjad
Keyword(s):  
Mechanical Properties ◽  
Tensile Properties ◽  
Pure Copper ◽  
Al Alloy ◽  
Base Metals ◽  
Mixed Structure ◽  
Nugget Zone ◽  
Butt Joints ◽  
Plunge Depth ◽  
Friction Stir

Abstract In the present study, butt joints of aluminum (Al) 8011-H18 and pure copper (Cu) were produced by friction stir welding (FSW) and the effect of plunge depth on surface morphology, microstructure and mechanical properties were investigated. The welds were produced by varying the plunge depth in a range from 0.1 mm to 0.25 mm. The defect-free joints were obtained when the Cu plate was fixed at the advancing side. It was found that less plunging depth gives better tensile properties compare to higher plunging depth because at higher plunging depth local thinning occurs at the welded region. Good tensile properties were achieved at plunge depth of 0.2 mm and the tensile strength was found to be higher than the strength of the Al (weaker of the two base metals). Microstructure study revealed that the metal close to copper side in the Nugget Zone (NZ) possessed lamellar alternating structure. However, mixed structure of Cu and Al existed in the aluminum side of NZ. Higher microhardness values were witnessed at the joint interfaces resulting from plastic deformation and the presence of intermetallics.

scholarly journals Effect of Stirring Pin Rotation Speed on Microstructure and Mechanical Properties of 2A14-T4 Alloy T-Joints Produced by Stationary Shoulder Friction Stir Welding

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1938
Author(s):  
Haifeng Yang ◽  
Hongyun Zhao ◽  
Xinxin Xu ◽  
Li Zhou ◽  
Huihui Zhao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Friction Stir Welding ◽  
Rotation Speed ◽  
Weld Nugget ◽  
Al Alloy ◽  
Nugget Zone ◽  
T Joints ◽  
Friction Stir ◽  
Stationary Shoulder ◽  
Microstructure And Mechanical Properties

In this study, 2A14-T4 Al-alloy T-joints were prepared via stationary shoulder friction stir welding (SSFSW) technology where the stirring pin’s rotation speed was set as different values. In combination with the numerical simulation results, the macro-forming, microstructure, and mechanical properties of the joints under different welding conditions were analyzed. The results show that the thermal cycle curves in the SSFSW process are featured by a steep climb and slow decreasing variation trends. As the stirring pin’s rotation speed increased, the grooves on the weld surface became more obvious. The base and rib plates exhibit W- or N-shaped hardness distribution patterns. The hardness of the weld nugget zone (WNZ) was high but was lower than that of the base material. The second weld’s annealing effect contributed to the precipitation and coarsening of the precipitated phase in the first weld nugget zone (WNZ1). The hardness of the heat affect zone (HAZ) in the vicinity of the thermo-mechanically affected zone (TMAZ) dropped to the minimum. As the stirring pin's rotation speed increased, the tensile strengths of the base and rib plates first increased and then dropped. The base and rib plates exhibited ductile and brittle/ductile fracture patterns, respectively.

Effects of Welding Wire Composition on Microstructure and Mechanical Properties of Welded Joint in Al-Mg-Si Alloy

2022 ◽  
Vol 905 ◽  
pp. 44-50
Author(s):  
Li Wang ◽  
Ya Ya Zheng ◽  
Shi Hu Hu
Keyword(s):  
Mechanical Properties ◽  
Fusion Zone ◽  
Heat Affected Zone ◽  
Welded Joint ◽  
Weld Zone ◽  
Xrd Analysis ◽  
Metallographic Analysis ◽  
Strengthening Effect ◽  
Welding Wire ◽  
Microstructure And Mechanical Properties

The effects of welding wire composition on microstructure and mechanical properties of welded joint in Al-Mg-Si alloy were studied by electrochemical test, X-ray diffraction (XRD) analysis and metallographic analysis. The results show that the weld zone is composed of coarse columnar dendrites and fine equated grains. Recrystallized grains are observed in the fusion zone, and the microstructure in the heat affected zone is coarsened by welding heat. The hardness curve of welded joint is like W-shaped, the highest hardness point appears near the fusion zone, and the lowest hardness point is in the heat affected zone. The main second phases of welded joints are: matrix α-Al, Mg2Si, AlMnSi, elemental Si and SiO2. The addition of rare earth in welding wire can refine the grain in weld zone obviously, produce fine grain strengthening effect, and improve the electrochemical performance of weld.

Sign in / Sign up

Export Citation Format

Share Document