Vibration joining of fiber‐reinforced thermosets

Abstract

Adhesive bonding is known to be particularly suitable for thermoset composites with continuous fiber reinforcement as it does not interrupt the fibers because of drilled holes. The frequently used two-part adhesives often require long curing times for the chemical reaction. At the Institute of Polymer Technology (LKT), a vibration-assisted hot melt bonding technique (vibration joining) was developed, which offers short cycle times and represents a modification of hot melt bonding, using the machine technology from vibration welding. It is suitable to join thermoplastics with thermoset materials or thermosets using a thermoplastic interlayer, by taking advantage of short cycle time and good lap shear strength, compared to bonding with reactive adhesives.

Mechanisms for combining polyamide and epoxy and their effects on mechanical performance—A review

“…The friction-melted PA can fill these pockets (Figure 18) and increase mechanical interlocking, and thereby bond strength, between the EP and the PA. This study quantifies the effect of surface roughness on bonding, suggesting that 119 pretreating a surface would improve its adhesion and mechanical properties. Adhesion could perhaps be further enhanced if the materials are combined before the EP is fully cured, allowing for chemical bonding in addition to mechanical interlocking.…”

“…He co-cures PA films and EP/carbon fiber prepregs to form a network of intermingled polymer chains before friction welding components together by melting the PA regions together. Unlike Beiss, 119 the PA and EP are combined before the EP cures, allowing the potential for PA-EP covalent bonding in addition to the mechanical interlocking. Room temperature single lap shear strength was 75% greater in Hou’s composite than in Beiss’s, illustrating the importance of chemical as well as mechanical interlocking for adhesion.…”

“…Beiss et al 119 used short glass fiber-reinforced PA 6 to adhere EP/woven glass fiber composites together. By using a friction welding process to adhere the PA composite to the EP, they observed an improvement of about 100% in the shear strength over samples created by overmolding thermosets with PA.…”

“…Mechanical interlocking between PA6 interlayer and carbon fiber composite. Reprinted from Polymer Composites, 31 (7), T. Beiss, Vibration joining of fiber-reinforced thermosets, Copyright 2009, with permission from John Wiley & Sons 119.…”

Effect of surface treatment on the performance of composite‐composite and composite‐metal adhesive joints

“…[1,2] Park et al [3] reported that due to the different natures of the two materials, joining composite components with metal alloys has been a serious problem. [4][5][6] Beiss et al [7] and Rhee et al [8] reported that the most common method of joining composite parts is adhesive bonding. Maressa et al [9] proposed that adhesive joints have a more even stress distribution, have lower stress concentration around corners, higher peel strength, and have a longer fatigue life than bolted joints.…”