Investigation and development of friction stir welding process for unreinforced polyphenylene sulfide and reinforced polyetheretherketone

Abstract

The joining of thermoplastics through welding offers numerous advantages over mechanical joining. Most importantly, it eliminates the use of costly fasteners and has only a limited effect on the strength of the parts being joined. Since it does not require the introduction of holes, loading pins, and the associated stress concentrations, a specific form of welding, friction stir welding (FSW), was investigated for the creation of butt joints of unreinforced polyphenylene sulfide (PPS) and short carbon fiber (CF)-reinforced polyetheretherketone (PEEK) plates. Unlike metals, analytical models and experimental results show that the heat generated by the FSW tool is insufficient to produce the heat required to weld thermoplastic materials. Therefore, a second heat source is required for preheating these thermoplastics. In this research, a resistance type surface heater was placed at the bottom of two identical weld pieces to produce good quality welds. Two types of shoulder design such as rotating shoulder and stationary shoulder were developed in this study. Taguchi’s design of experiment method was utilized to develop the welding process, where heating duration, material temperature, tool rotational speed, and tool traverse speed were used as the welding parameters. One of the process parameters, tool traverse speed, had significant influence on the tensile strength of PPS samples. While PPS sample showed relatively lower tensile strength with higher traverse speed, short CF-reinforced PEEK samples had higher tensile strength with a higher traverse speed. In addition to tensile tests, fracture toughness tests were performed for both PPS and PEEK samples to observe the influence of unwelded segments in the welded parts. In this study, joint efficiency of PEEK samples was found to be higher than that of PPS samples. Micrographs of PEEK samples showed uniform homogenous mixture of part materials.

Fabrication of a novel hydroxyapatite/polyether ether ketone surface nanocomposite via friction stir processing for orthopedic and dental applications

“…Although the low temperature has been previously applied, a strong adhesion between the PEEK substrate and HA layer is hard to achieve (Filiaggi et al 1991;Rabiei and Sandukas 2013;Radin and Ducheyne 1992). In order to address the drawbacks, friction stir processing (FSP),a solid phase processing technique, can be employed to modify the surface of PEEK (Ahmed et al 2018). For this method, the additives are homogenously mixed with the substrate material without the need for melting the substrate.…”

Joining of Fibre-Reinforced Thermoplastic Polymer Composites by Friction Stir Welding—A Review

“…The literature shows that it is already possible to join several thermoplastics by FSW, such as acrylonitrile butadiene styrene (ABS) [24][25][26][27], polyamide 6 and 66 (PA6 and PA66) [28][29][30], polycarbonate (PC) [31,32], polyethylene (PE) [33][34][35], polylactic acid (PLA) [36], polymethylmethacrylate (PMMA) [37][38][39], polyphenylene sulfide (PPS) [40], polypropylene (PP) [41][42][43], and polyvinyl chloride (PVC) [44]. Since 2011, FSW is also being studied for the joining of FRTP composites reinforced with chopped fibres [45,46].…”

“…Since 2011, FSW is also being studied for the joining of FRTP composites reinforced with chopped fibres [45,46]. Most of the publications found are related to PP reinforced with chopped GF [3,5,[45][46][47][48] or chopped CF [3,5,48,49], but matrices of PA6 [50][51][52][53], PC [54] and polyetheretherketone (PEEK) [40] have also been reported. The studies found in the literature are still very much focused on the feasibility of the technology.…”

Analysis and prediction of the joint strength of friction stir welded Aluminium 5754 to polyamide using response surface methodology and artificial neural network

“…11 The concepts of frictional heating and plastic deformation are combined in FSW, a cutting-edge solid-state joining method in which a thermomechanical way is used to plasticize materials. [12][13][14][15][16] The stirring results in mixing, and later a joint is developed at a temperature below the melting point of the base materials. 17 Thus, FSW is a better joining process for decreasing distortions and residual stresses that affect traditional welding processes.…”