H. Tirband, D. Akbari, M. Sadeh,
Volume 8, Issue 1 (Journal OF Welding Science and Technology 2022)
Todays, application of composite materials has been increased in various industries due to their special strength properties and also other unique features. One of the important things during making of such materials, is their connection to each other. In this article, the Joining of heat-hardened parts with surface preparation with the help of laser, simple and rough, has been investigated. The main goal is to investigate the better surface adhesion mechanisms of the connection compared to the simple surface, as well as to create practical approaches to increase the adhesion strength of the thermosetting parts. The composites were made of heat-hardened epoxy resin (which hardens after 12 hours at room temperature) and two-dimensional woven glass fibers and were connected by glue after volume heating at a temperature of 180-200 degree Celsius. In this research, the overlapping surface of the part was engraved by laser in circular patterns. The raw parts were prepared by manual polishing and mechanical abrasion. The results show that by examining the effect of surface roughness and composite thickness, the highest value of shear strength is related to the surface roughness compared to other preparation methods. Surface preparation increases the amount of adhesive penetration in the parts and expands the tensile strength. The thickness also has a conditional effect on the strength of the connection.
