Mechanical properties and microstructure of joints in AZ31 thin sheets obtained by friction stir welding using “pin” and “pinless” tool configurations

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.

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Similar and dissimilar friction-stir welding of an PM aluminum-matrix hybrid nanocomposite and commercial pure aluminum: Microstructure and mechanical properties

Materials Science and Engineering A ◽

10.1016/j.msea.2016.04.078 ◽

2016 ◽

Vol 666 ◽

pp. 225-237 ◽

Cited By ~ 46

Author(s):

F. Khodabakhshi ◽

A. Simchi ◽

A.H. Kokabi ◽

A.P. Gerlich

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Pure Aluminum ◽

Aluminum Matrix ◽

Hybrid Nanocomposite ◽

Friction Stir ◽

Microstructure And Mechanical Properties ◽

Dissimilar Friction Stir Welding ◽

Commercial Pure Aluminum

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Microstructure and Mechanical Properties at the Unsteady Areas of Non-Linear Friction Stir Welding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1059 ◽

2007 ◽

Vol 561-565 ◽

pp. 1059-1062 ◽

Cited By ~ 1

Author(s):

H. Takahara ◽

Masato Tsujikawa ◽

Sung Wook Chung ◽

Y. Okawa ◽

Kenji Higashi

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Welding Parameter ◽

Butt Joints ◽

Friction Stir ◽

Non Linear ◽

Linear Friction ◽

Fsw Parameters ◽

Five Axis ◽

Welding Direction

The influence of tool control in non-linear friction stir welding (FSW) on mechanical properties of joints was investigated. FSW is widely applied to linear joints. It is impossible for five axis FSW machines, however, to keep all the FSW parameters in optimum conditions at non-linear welding. Non-linear FSW joints should be made by compromise with the order of priority for FSW parameters. The tensile test results of butt joints with rectangular change in welding direction on plate plane (L-shaped butt joints) with various welding parameter change. It was found that turn to the retreating side is encouraged when welding direction change. And the method of zero inclination tool angle is effective at non-linear and plane welding.

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