Modetechnologie und Textiltechnik

Experimental Investigations on Bio-Inspired Sisal Fiber Reinforced Epoxy Composite for Foot Prosthetic Application

Temesgen Tilahun* and Samuel Tesfaye

The prosthetic foot is a device used as a replacement for amputees in the place of the biological part to have safe locomotion The major concern of this work is to investigate tensile strength, flexural strength, impact strength, compressive strength, and water absorption of spider web pattern sisal fiber reinforced epoxy composite. The prosthetics industry uses High-density Polypropylene (HPP) and composite material (carbon or glass) or hybrid fiber-reinforced epoxy composites. The high cost of fibers and low-strength PP are the problems of current prosthetic production. This research targets to model a lower limb prosthetic foot with better mechanical properties and affordable natural fiber (sisal) reinforced composite based on bio-inspired fiber orientation techniques. Hand layup manufacturing techniques were used to prepare a composite of 70% of epoxy matrix and 30% of sisal fiber (50 mm long fibers) knitted in spider web orientations. The fiber was treated with 5% NaOH for five hours and dried in an oven for two hours. Then five layered composites stacked together in the sequence of (0/3/6/9/12) degrees was prepared. The experimental results indicate that a spider web-oriented sisal fiber-reinforced epoxy composite has superior properties with a tensile strength of 45.6 MPa, a tensile modulus of 1.2 GPa, a flexural strength of 76.78 MPa, a flexural modulus of 3.42 GPa, the compression strength of 65.55 Mpa and compressive modulus of 2.229 MPa, impact strength of 12.72 J/cm² with impact Energy resistance of 4.6 J and an average water absorption capacity of 3%. Hence the spider web-oriented sisal fiber-reinforced epoxy composite can be used as an alternative material for prosthetic foot manufacturers as suggested.