Influence of Polycrystalline Structure on Dynamic Strength and Fracture Character of an Aluminum Alloy in Different Welding Joint Zones

Abstract6082-T6 aluminum alloy plate with thickness of 42mm was butt welded by friction stir welding (FSW) from two sides. The microstructures of the joints exhibited different grain sizes because of unequal frictional heating and plastic flow during FSW process. The transition from the heat affected zone (HAZ) to the nugget zone (NZ) in thermos-mechanical affected zone of advancing side (AS-TMAZ) was more sudden than thermos-mechanical affected zone of retreating side (RS-TMAZ). Kissing bond (KB) defect throughout the entire FSW joint was displayed both at the grain boundary and in the interior of the grain with semi-continuous bands. KB had no direct effect on tensile properties. Vickers hardness of the FSW joint was lower than the BM because its high heat input, dissolved and coarsened precipitates and little to the grain size after FSW. Hardness distribution of double-sided welding joint showed X-shaped area softening characteristics, that is to say the lowest hardness was the junction of two welding joint of NZ and the junction of TMAZ and HAZ. The tensile fracture position occurred in the lowest hardness region of the FSW joint, and it did not occur in the KB defect position.

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The adjustment strategy of welding parameters for spray formed 7055 aluminum alloy underwater friction stir welding joint

Materials & Design ◽

10.1016/j.matdes.2015.09.038 ◽

2015 ◽

Vol 88 ◽

pp. 1366-1376 ◽

Cited By ~ 21

Author(s):

Qingzhao Wang ◽

Zhixia Zhao ◽

Yong Zhao ◽

Keng Yan ◽

Hao Zhang

Keyword(s):

Aluminum Alloy ◽

Friction Stir Welding ◽

Welding Parameters ◽

Friction Stir ◽

Welding Joint ◽

Adjustment Strategy ◽

Underwater Friction Stir Welding ◽

7055 Aluminum Alloy

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Microstructural characteristics and mechanical properties of friction stir lap welding joint of Alclad 7B04-T74 aluminum alloy

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-014-6718-2 ◽

2015 ◽

Vol 78 (9-12) ◽

pp. 1415-1425 ◽

Cited By ~ 43

Author(s):

Huijie Liu ◽

Yunqiang Zhao ◽

Yanying Hu ◽

Shixuan Chen ◽

Zhe Lin

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Friction Stir Lap Welding ◽

Microstructural Characteristics ◽

Friction Stir ◽

Welding Joint ◽

Lap Welding

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

Materials ◽

10.3390/ma14185287 ◽

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.

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The Effect of Single Pulse, Double Pulse and ForceArc MIG Welding Technology on Mechanical Properties of Welding Joint for 5083 Aluminum Alloy Used in High-Speed Train Body

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.337.460 ◽

2011 ◽

Vol 337 ◽

pp. 460-465

Author(s):

Lei Su ◽

Yuan Nie ◽

Hua Ji ◽

Chuan Ping Ma ◽

Shao Hua Yan ◽

...

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

High Speed ◽

Single Pulse ◽

Double Pulse ◽

High Speed Train ◽

Welding Joint ◽

5083 Aluminum Alloy ◽

Very High

The technology of lightening manufacture for aluminum alloy train body is one key of manufacturing high-speed train . The train body is a whole bearing loading tubular structure which is welded together by the large, hollow, thin-walled aluminum extrusion. Therefore，the demand for welding quality of aluminum alloy train body is very high，and the mechanical properties of joints severely affected the overall strength of welded components. To solve this problem ,we use the 421 EXPERT forceArc MIG of PHOENIX series of German EWM company to perform three types of experiments of single pulse, double pulse, and forceArc welding ,and then effect of three welding methods on mechanical properties of Welding joint for 5083 aluminum alloy used in high-speed train body is compared.

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