Multi-Objective Optimization of Resistance Welding Process of GF/PP Composites

Abstract

Thermoplastic composites (TPCs) are promising materials for aerospace, transportation, shipbuilding, and civil use owing to their lightweight, rapid prototyping, reprocessing, and environmental recycling advantages. The connection assemblies of TPCs components are crucial to their application; compared with traditional mechanical joints and adhesive connections, fusion connections are more promising, particularly resistance welding. This study aims to investigate the effects of process control parameters, including welding current, time, and pressure, for optimization of resistance welding based on glass fiber-reinforced polypropylene (GF/PP) TPCs and a stainless-steel mesh heating element. A self-designed resistance-welding equipment suitable for the resistance welding process of GF/PP TPCs was manufactured. GF/PP laminates are fabricated using a hot press, and their mechanical properties were evaluated. The resistance distribution of the heating elements was assessed to conform with a normal distribution. Tensile shear experiments were designed and conducted using the Taguchi method to evaluate and predict process factor effects on the lap shear strength (LSS) of GF/PP based on signal-to-noise ratio (S/N) and analysis of variance. The results show that current is the main factor affecting resistance welding quality. The optimal process parameters are a current of 12.5 A, pressure of 2.5 MPa, and time of 540 s. The experimental LSS under the optimized parameters is 12.186 MPa, which has a 6.76% error compared with the result predicted based on the S/N.

Optimizing the Process of Spot Welding of Polycarbonate-Matrix-Based Unidirectional (UD) Thermoplastic Composite Tapes

“…Zhang et al optimized their process based on lap shear tests performed according to the ASTM 1002 standard. In addition, they examined the failure modes of the fractured bond [29]. Huang et al reviewed the potential of joining thermoplastic polymers and polymer composites together by means of friction stir welding based on shear strength.…”

Computational and experimental study on the resistance welding process of a glass fiber‐reinforced epoxy‐based composite with thermoplastic interlayer adherent

“…18 Resistance welding has been reported to join thermoplastics-based composites reinforced by continuous glass or carbon fibers. [18][19][20][21] Experimental and computational techniques have been conducted by using single lap shear tests to characterize the welding quality and the finite element analysis (FEA) to simulate the heat transfer within composite joints during welding processes. 22,23 The effect of welding parameters, such as electricity power, clamping distance, resistance of heating element, and welding pressure, has been widely investigated.…”

The effect of flame treatment on the compressive strength of composite sandwich panels made of pure epoxy resin H‐shaped structures and hollow glass bead/epoxy resin composite material

“…Upon compression, HGB/EP will display malleable behavior, 22 while the low interfacial strength may result in premature failure and delamination of the sandwiched panel during compression 25,26 . In the realm of surface bonding properties of bonding materials, flame treatment has emerged as a promising surface treatment method in industrial applications due to its attributes of automation, cost‐effectiveness, simplicity, and rapidity, 27,28 yielding satisfactory outcomes 29–33 . Consequently, the application of flame treatment to the pure EP H‐shaped structure is incorporated in this study to augment its bonding strength with HGB/EP.…”