Zero-flow: a novel approach to continuous ultrasonic welding of CF/PPS thermoplastic composite plates

Abstract

Continuous ultrasonic welding of plastic films, fabrics, and even thermoplastic composite prepreg tape is a common industrial practice. However, continuous ultrasonic welding of stiff thermoplastic composite plates is challenging due to squeeze flow of resin at the welding interface, and significant local deformation of the welding stack, that are generally needed to achieve strong welds. This paper presents a novel approach to continuous ultrasonic welding of thermoplastic composite plates based on zero-flow welding. The proposed technique can create strong welds before any squeeze flow takes place at the interface. It is enabled by the use of very thin flat energy directors, owing to simultaneous melting of both energy director and adherends' matrix. The results prove the feasibility and indicate the potential for high-strength welds between thermoplastic composite plates at very high speed.

Advances in Ultrasonic Welding of Thermoplastic Composites: A Review

“…Similar studies were carried out by Senders et al [95] and Palardy et al [73,96] A comparison of flat energy director (PPS) and triangular energy director was also studied by Villegas et al, where CF/PPS composite was used [97]. In this investigation, they showed that the ED configuration with triangular strips has two more additional stages as compared to the conventional five stages in the flat ED study.…”

“…Similar studies were carried out by Senders et al [95] and Palardy et al [73,96] on the effect of flat energy directors, and using the displacement control mode with different material systems. CF/PPS and CF/PEI composites were used for the investigation, respectively.…”

“…CF/PPS and CF/PEI composites were used for the investigation, respectively. Senders et al investigated three different welding conditions, with fully welded overlap, spot welding and continuous welding of the adherends [95]. The investigation is to show that zero flow welding can be carried out, i.e., through continuous welding a higher weld strength, which can be obtained without local deformation of the adherends, as the sonotrode moves along the weld line.…”

Continuous ultrasonic welding of thermoplastic composites: Enhancing the weld uniformity by changing the energy director

“…[14][15][16] Continuous ultrasonic welding (CUW) has been shown to be a fast and feasible welding technique. 17 Senders et al demonstrated the feasibility of CUW by joining 100-mm-long carbon fiber-reinforced polyphenylene sulfide (CF/PPS) plates with a continuously welded seam. A thin (0.08 mm thick) PPS film energy director was used to minimize squeeze flow at the weld interface (''zero-flow'' welding).…”

Corrugated composites: production-integrated quality assurance in carbon fiber reinforced thermoplastic sine wave beam production

“…Especially the field of joining and welding of thermoplastic composites has been studies extensively with a broad comprehensive knowledge base available. [1][2][3][4][5][6][7][8][9][10] Advanced manufacturing techniques have been discussed and demonstrated. [11][12][13][14][15] The so-called TAPAS (Thermoplastic Affordable Primary Aircraft Structure) consortium has demonstrated a number of large-scale thermoplastic components for aerospace applications since its launch in 2009.…”