The Effect of Welding Parameters on the Morphology and Mechanical Properties of AA6061-T6/CF-PPS Friction Stir Lap Welding Joints
Abstract
1. Introduction
2. Materials and Methods
3. Results and Discussion
3.1. The Effect of Spindle Rotation Speed on Welding Quality
3.2. The Effect of Welding Speed on Welding Quality
3.3. The Effect of Plunge Depth on Welding Quality
4. Conclusions
- The macro mechanical interlocking structure is the main connection form that facilitates the successful connection of aluminum alloy and CF-PPS dissimilar materials. The concave shoulder facilitates the outward extension of the aluminum at the edge of the stirring zone, thereby forming a hook that serves to connect the upper and lower plates. The inward curvature of the aluminum anchor serves to augment the connection area between the two plates, thereby enhancing the tensile strength of the weld.
- It has been demonstrated that, under welding parameters of 1800 rpm rotation speed, 40 mm/min welding speed, and 0.2 mm plunge depth, the tensile strength of the joint can reach a maximum value of 9.41 MPa. Concurrently, the microscopic mixture formed by the adhesion between the metal and polymer inside the SZ also increases the tensile strength of the joint.
- At low rotation speeds (1600 rpm) and low welding speeds (10 mm/min), an effective mechanical interlocking structure cannot be formed at the center of the weld, which weakens the connection strength. The low rotation speed fails to provide sufficient frictional heat input, resulting in incomplete plasticization of the aluminum below, failure to form aluminum anchors on both sides of the SZ, and the formation of hollow at the bottom. The low welding speed leads to excessive heat generation by friction, resulting in thermal decomposition of a portion of the resin matrix in CF-PPS, which subsequently forms a gas phase. This gas phase expands within the base material, creating cavities, while the aluminum anchors generated on the AS undergo significant damage.
- When the rotation speed and welding speed, the two main parameters affecting the heat input of the welding process are appropriately selected and kept constant. A smaller plunge depth can form an effective mechanical interlocking structure. Excessive plunge depth will thin the weld and reduce the joint strength.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Chemical Composition (wt%) | |||||||
---|---|---|---|---|---|---|---|
Mg | Fe | Si | Cu | Zn | Mn | Cr | Al |
0.8–1.2 | 0.7 | 0.4–0.8 | 0.15–0.4 | 0.25 | 0.15 | 0.04–0.35 | Base |
Mechanical Properties | ||
---|---|---|
Yield Strength (MPa) | Tensile Strength (MPa) | Extension Rate (%) |
240 | 310 | 8 |
Density (g/cm3) | Melting Temperature (°C) | Tensile Strength (MPa) | In-Plane Strength (MPa) | Extension Rate (%) |
---|---|---|---|---|
1.35 | 295 | 170 | 119 | 1.2 |
FSLW Experimental Program | Rotation Speed | Welding Speed | Plunge Depth | Inclination Angle |
---|---|---|---|---|
The effect of rotation speed | 1600 rpm | 40 mm/min | 0.2 mm | 2° |
1700 rpm | ||||
1800 rpm | ||||
1900 rpm | ||||
2000 rpm | ||||
The effect of welding speed | 1800 rpm | 10 mm/min | 0.2 mm | 2° |
20 mm/min | ||||
30 mm/min | ||||
40 mm/min | ||||
50 mm/min | ||||
The effect of plunge depth | 1800 rpm | 40 mm/min | 0.1 mm | 2° |
0.15 mm | ||||
0.2 mm | ||||
0.25 mm | ||||
0.3 mm |
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Xu, W.; Lin, Y.; Feng, Q.; Wang, Y.; Wang, J.; Niu, S.; Lou, M. The Effect of Welding Parameters on the Morphology and Mechanical Properties of AA6061-T6/CF-PPS Friction Stir Lap Welding Joints. Metals 2025, 15, 1049. https://doi.org/10.3390/met15091049
Xu W, Lin Y, Feng Q, Wang Y, Wang J, Niu S, Lou M. The Effect of Welding Parameters on the Morphology and Mechanical Properties of AA6061-T6/CF-PPS Friction Stir Lap Welding Joints. Metals. 2025; 15(9):1049. https://doi.org/10.3390/met15091049
Chicago/Turabian StyleXu, Wenhao, Yongyong Lin, Qiaobo Feng, Yangjun Wang, Jie Wang, Sizhe Niu, and Ming Lou. 2025. "The Effect of Welding Parameters on the Morphology and Mechanical Properties of AA6061-T6/CF-PPS Friction Stir Lap Welding Joints" Metals 15, no. 9: 1049. https://doi.org/10.3390/met15091049
APA StyleXu, W., Lin, Y., Feng, Q., Wang, Y., Wang, J., Niu, S., & Lou, M. (2025). The Effect of Welding Parameters on the Morphology and Mechanical Properties of AA6061-T6/CF-PPS Friction Stir Lap Welding Joints. Metals, 15(9), 1049. https://doi.org/10.3390/met15091049