scholarly journals The Effect of Plug Rotation Speed on Micro-Structure of Nugget Zone of Friction Plug Repair Welding Joint for 6082 Aluminum Alloy

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5287
Author(s):  
Defu Li ◽  
Xijing Wang
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Rotation Speed ◽  
Base Material ◽  
Weld Nugget ◽  
Nugget Zone ◽  
Repair Welding ◽  
Welding Joint ◽  
6082 Aluminum Alloy ◽  
Plug Repair

This paper carried out the friction plug repair welding of 6082 aluminum alloy keyhole defects by using the method of friction heating between shaft shoulder and base material. In addition, a well-formed friction plug welding joint was obtained at different plug rotation speeds. In order to study the influence mechanism of plug rotation speeds on the microstructure of the weld nugget zone, EBSD technology was used to analyze the grain morphology, grain size and grain boundary characteristics of the weld nugget zone under different rotation speeds of the plug rod. The results show that in the nugget zone, the grain was fine and equated crystals refinement, and there was a preferred orientation. The deformation texture components in the welded nugget zone increased with the plug rotation speed from 1600 to 2000 rpm. However, the grain size first decreased and then increased, while the components in the High-Angle Boundary first increased and then decreased.

Nonuniformity of Mechanical Property in the Weld Zone of Friction Stir Welded 7050 Aluminum Alloy Joint

2011 ◽  
Vol 189-193 ◽  
pp. 3560-3563
Author(s):  
Yu Wen Tian ◽  
Fei Xu ◽  
Wen Ya Li ◽  
Zhong Bin Tang
Keyword(s):  
Mechanical Property ◽  
Aluminum Alloy ◽  
Elastic Modulus ◽  
Weld Zone ◽  
Base Material ◽  
Weld Nugget ◽  
Second Phase ◽  
Nugget Zone ◽  
Friction Stir ◽  
7050 Aluminum Alloy

The distribution of mechanical property in the weld zone of friction stir welded 7050 aluminum alloy joint along the plane perpendicular to the welding direction was experimentally investigated by the non-contact measurement method. The results show that the elastic modulus presents a W-shape distribution across the weld zone. The elastic modulus in the weld nugget zone is increased due to the grain refinement. In addition, the elastic modulus in the advancing side is slightly less than that in the retreating side possibly because of the relatively higher temperature in the advancing side during the welding process. The strength in the vicinity of weld center is decreased while the ductility is enhanced. The tensile strength and yield strength in the weld nugget zone and thermo-mechanically affected zone are significantly decreased while the elongation is increased due to the change of strengthening mechanism. In the heat affected zone the strength is decreased compared to the base material because the second phase grows up.

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.

Influence of Friction Stir Processing Parameters on Anisotropic Behavior Property of 5086-O Aluminum Alloy

2011 ◽  
Vol 702-703 ◽  
pp. 348-351
Author(s):  
Shivanna Pradeep ◽  
Sumit Kumar Sharma ◽  
Vivek Pancholi
Keyword(s):  
Aluminum Alloy ◽  
Friction Stir Processing ◽  
Rotation Speed ◽  
Base Material ◽  
Processing Parameters ◽  
Mechanical Anisotropy ◽  
Al Alloy ◽  
Anisotropic Behavior ◽  
Planar Anisotropy ◽  
Friction Stir

In the present work, 5086 Al alloy is subjected to single and multi pass friction stir processing (FSP) to modify microstructure and mechanical anisotropy. The processing is carried out at constant rotation speed of 1025 rpm and different traverse speeds of 30 mm/min and 50 mm/min with and without cooling. Mechanical anisotropy is evaluated in terms of normal and planar anisotropy by performing tensile test in 0, 45 and 90o direction to processing direction. Material processed using multi pass FSP at 30 mm/min is showing lower planar anisotropy as compared to base material. The mechanical anisotropy property is correlated with the development of micro texture.

scholarly journals Incorporating oxygen-free copper to improve the microstructure and mechanical properties of friction-stir-welded joints for aluminum alloys

2018 ◽  
Vol 25 (6) ◽  
pp. 1219-1228
Author(s):  
Her-Yueh Huang ◽  
Chung-Wei Yang ◽  
Wen-Yao Deng
Keyword(s):  
Mechanical Properties ◽  
Rotation Speed ◽  
Welding Process ◽  
Weld Nugget ◽  
Nugget Zone ◽  
Friction Stir ◽  
Copper Particles ◽  
Dissimilar Metal ◽  
Tool Rotation ◽  
Traveling Speed

AbstractThe main objective of the present work was to establish a friction-stir-welding process to weld dissimilar metal joints on AA6082 and AA6066 aluminum alloy plates. Joints were made while varying tool rotation speed at a constant traveling speed and at the same time adding oxygen-free copper reinforcement inside the weld nugget for the purpose of analyzing the microstructural evolution and mechanical properties of the joint. Results showed that the morphology of the microstructure in the weld nugget changed significantly with rotation speed. Optical microscopy, scanning electron microscopy, and energy dispersive spectroscopy analyses revealed that oxygen-free copper particles could be uniformly dispersed into the weld nugget because of higher rotation speeds. Because of the presence of reinforcement particles homogenously distributed inside the nugget zone, the mechanical properties, such as ultimate tensile strength and hardness of weld joint, were greatly improved.

Microstructure and Mechanical Properties of Friction Stir Welding Joint of Pure Copper

2011 ◽  
Vol 418-420 ◽  
pp. 1520-1523
Author(s):  
Yong Zhao ◽  
You Li Ye ◽  
Keng Yan ◽  
Li Long Zhou
Keyword(s):  
Mechanical Properties ◽  
Friction Stir Welding ◽  
High Speed ◽  
Bonding Temperature ◽  
Pure Copper ◽  
High Speed Steel ◽  
Weld Nugget ◽  
Nugget Zone ◽  
Friction Stir ◽  
Welding Joint

Microstructures and mechanical properties of pure copper weld joints are discussed under different parameters of friction stir welding. The results reveal that it is conducive to the formation of compact joint in friction stir welding by applying high speed steel tool with high anti-bonding temperature. The friction stir welding joint with compact and defect-free microstructure could be obtained when the tool rotation rate is 1250- 1650 r/min and the tool traverse speed is 20-50 mm/min. Intensively plastic deformation occurs in the soften materials of the weld nugget zone and numerous crystal particles are broken under the influence of tool stirring. The microstructure of weld nugget zone is composed of tiny isometric crystals, which is due to the dynamic recrystallization of broken crystal particles. The structure of thermo-mechanical affected zone on both sides is asymmetric. Obvious boundary of the thermo affected zone could be seen on the advancing side, and the plastic streamline is apparent.

Investigations on the Hardness Distribution and Microstructure of Friction-Stir-Welded 6082 Aluminum Alloy

2020 ◽  
Vol 993 ◽  
pp. 116-122
Author(s):  
Kun Yuan Gao ◽  
Bo Li ◽  
Yu Sheng Ding ◽  
Hui Huang ◽  
Sheng Ping Wen ◽  
...  
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Grain Boundaries ◽  
Base Metal ◽  
Heat Affected Zone ◽  
Hardness Distribution ◽  
Secondary Phases ◽  
Friction Stir ◽  
Β Phase ◽  
6082 Aluminum Alloy

The hardness and microstructure of friction stir welded (FSW) 6082 aluminum alloy joint were investigated by Vickers microhardness test, optical microscopy (OM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The hardness distribution is in a W shape, and from the base metal to the heat affected zone (HAZ) the hardness decreases from 103 HV to 72 HV, then gradually increases to 84 HV at the nugget zone (NZ). The grains of base metal (BM) are elongated and composed of a great quantity of low-angle grain boundaries. The nugget zon was of quite fine recrystallized grains. For the thermomechanical affected zone (TMAZ), the grain size is a little smaller than that of base metal and some low-angle grain boundaries remain. In the heat affected zone, the grain size was similar to that of the base metal. The β'' phase (Mg5Si6) and Al-Mn-Si particles are dispersed in the base metal. . In the heat affected zone, β'' phase transforms to β' phase (Mg9Si5). The hardness distribution in a W-shape was discussed on the basis of grain size, density of low-angle grain boundary and secondary phases.

Microstructures and Properties of FSW Joints of AZ31B Mg Alloy

2011 ◽  
Vol 291-294 ◽  
pp. 855-859 ◽  
Author(s):  
Si Rong Yu ◽  
Xian Jun Chen
Keyword(s):  
Mechanical Properties ◽  
Heat Affected Zone ◽  
Welded Joint ◽  
Base Material ◽  
Alloy Sheet ◽  
Weld Nugget ◽  
Mg Alloy ◽  
Material Strength ◽  
Nugget Zone ◽  
Friction Stir

The extruded AZ31B Mg alloy sheet was welded with friction stir welding. The microstructures and mechanical properties of the welded joint were investigated. The results show that the grains in the weld nugget zone were small, uniform and equiaxed. The grains in thermo-mechanical affected zone were stretched and relatively small, but were not as small and uniform as those in the weld nugget zone. The grains in the heat-affected zone were relatively coarse. The fracture of the welded joint occurred mainly in the heat affected zone. The tensile strength of the welded joints was up to 257.4 MPa and was 87.9% of the base material strength. The microhardness in the weld nugget zone was higher. The microhardness in the thermo-mechanical affected zone and heat affected zone were lower than that in the weld nugget zone. The microhardness in the weld nugget zone increased from the upper surface to the bottom.

Microstructure and Mechanical Properties of Cu-Cr-Zr Alloy by Friction Stir Welding

2012 ◽  
Vol 602-604 ◽  
pp. 608-611
Author(s):  
Di Qiu He ◽  
Rui Lin Lai ◽  
Shao Hua Xu ◽  
Kun Yu Yang ◽  
Shao Yong Ye ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Friction Stir Welding ◽  
Rotation Speed ◽  
Base Material ◽  
Traverse Speed ◽  
Nugget Zone ◽  
Alloy Plate ◽  
Friction Stir ◽  
Microstructure And Mechanical Properties ◽  
Zr Alloy

In this study, Cu-Cr-Zr alloy joints are successfully fabricated by friction stir welding (FSW). Defect-free weld are produced on 12mm thick Cu-Cr-Zr alloy plate useing a non-consumable tool with a specially designed and shoulder with a constant rotation speed and a fixed traverse speed. The effect of friction stir welding (FSW) on the microstructure and mechanical properties of Cu-Cr-Zr alloy joints are investigated in details: The joints showed the presence of various zones such as nugget zone (NZ) and thermo-mechanically affected zone (TMAZ) and base metal (BM), the microhardness and the tensile strength of welded joints are lower than that of the base material.

Effect of pin-profiles on thermal cycle, mechanical and metallurgical properties of friction stir–welded aviation-grade aluminum alloy

2019 ◽  
Vol 233 (11) ◽  
pp. 2183-2195 ◽  
Author(s):  
Shubham Verma ◽  
Meenu Gupta ◽  
Joy Prakash Misra
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Electron Backscatter Diffraction ◽  
Volume Ratio ◽  
Nugget Zone ◽  
Friction Stir ◽  
Metallurgical Properties ◽  
Swept Volume ◽  
Backscatter Diffraction ◽  
Tool Pin

Current research is an attempt to choose suitable pin-profile for friction stir welding of aviation-grade aluminum alloy (AA6082). Six tool pin-geometries (T1–T6), that is, threaded cylindrical, taper cylindrical, four slotted, square, triangular and inverted tapered with two flat faces are used to fabricate joints. Mechanical and metallurgical properties of the joints are assessed and allied with nugget zone grain size and thermal properties. The swept volume ratio and pulsating-stirring action of pin-profiles are also quantified. It is observed that square pin-profile provides joint with superior mechanical and metallurgical properties owing to higher pulsating-stirring action and sufficient swept volume ratio. The maximum tensile strength of 300 MPa is obtained by employing square pin-profile tool. Beside this, electron backscatter diffraction analysis has been conducted to critically examine the effect of pin-profiles on grains distribution of nugget zone of friction stir–welded joints. The minimum grain size of 5.48 μm is obtained using square pin-profile.

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