Experimental investigation of single-lap bolted and bolted/bonded (hybrid) joints of polymeric plates

Abstract

In this study, the joint strengths of single-lap bolted and bolted/bonded (hybrid) joints formed by using four different engineering plastics were experimentally investigated. High-density polyethylene (HDPE), ultra-high molecular weight polyethylene, Delrin (POM), and Teflon were used as plate materials in single-lap connections. Standard M6 bolts were used in bolt connections. The specimens were prepared as single bolted, double bolted, single bolted/bonded, and double bolted/bonded in 20, 40, and 60 mm single-lap lengths. Weicon company's RK-7100 two-component adhesive was used as the adhesive. Tensile tests were carried out with the displacement control of 2 mm/min. After the tensile tests, load-extension graphs were created for each connection type, and the strengths of the connections were compared with each other. Three parameters were used to evaluate the strength of the additional lap joints. These are effect of the bolt numbers, effect of the adhesive, and effect of single-lap length. Depending on the plate material, double-bolt connections performed 20-56% better than single-bolt connections. The adhesive had no effect on ultimate joint strength. As the overlap length increased, an increase was generally observed in the joint strength of the specimens. Depending on the overlap length increase from 20 to 60 mm, the strength of the single-bolt confiGürations of HDPE-B specimens was found to be approximately two times that of the best results. When polymeric plates are compared among themselves, double-bolted Delrin (POM) specimens exhibited the highest joint strength in all single-lap lengths.