Fabrication and characterization of weld attributes in hot gas welding of alkali treated hybrid flax fiber and pine cone fibers reinforced poly-lactic acid (PLA) based biodegradable polymer composites: studies on mechanical and morphological properties

Abstract

The contemporary times have witnessed a lot of interest in fabricating green composites because of its biodegradability, durability, affordability, ease of manufacturing and its potential to replace existing commercial goods in the field of engineering applications. The green composites are envisaged to replace synthetic polymer-based composites since the green composites are fabricated using the biodegradable polymers reinforced with natural fibers. In this research work, Flax Fiber and Pine Cone Fibers are reinforced in Poly-lactic Acid (PLA) matrix. The green composites are fabricated using compression moulding technique in different nominations as per the weight fraction such as (90:10), (80:20) and (70:30). It was noticed that a higher tensile strength of 27 MPa is observed in case of group 2 (80:20) specifically for the composite having 80% of matrix and 14% flax and 6% pine cone fibers. An IoT based automatic hot gas welding method was used to join the fibers by considering various input parameters like stand of distance, weld rate, specimen groove geometry, and composition. The mechanical testing of the weld specimens was carried. It was observed that the weld joints having higher stand of distance were observed to have less tensile strength as compared to others and the fracture points of such specimens were observed to be at the weld bead. SEM analysis of the fracture point validated the observations from the mechanical characterization.

Keywords

• Green composites
• Biodegradability
• Polymer-based composites
• Flax fiber and pine cone fibers
• Poly-lactic acid (PLA)
• Mechanical testing