Drop-weight Impact Responses of Kenaf Fibre-Reinforced Composite-Metal Laminates: Effect of Chemical Treatment and Fibre Composition

Recently, fiber-metal laminates have gained high attention from material scientists and engineers, particularly when it comes to impact-critical applications. When compared to metallic alloys and composite materials, fiber-metal laminates offer several distinguishing advantages. This work intends to evaluate the low-velocity response of kenaf fiber-reinforced polypropylene metal-composite laminates with various fiber compositions, in line with the current trend of using natural fiber as possible reinforcement in composite materials. In addition, a comparison was made between the low-velocity impact response of non-treated and chemical-treated kenaf fiber-reinforced composite-metal laminates. A hot molding compression technique was employed to fabricate the laminates. Low-velocity impact tests were performed based on ASTM D7136 to determine the peak force, maximum displacement, and energy absorption of the materials. The results confirmed that NaOH treatment and increased fiber content resulted in a higher peak force of NaOH-treated kenaf-based metal laminates. For NaOH-treated laminates, the peak force of laminates with 70 wt% was found to be 11.20% higher than laminates with 50 wt% at the impact energy of 60 J. At fiber content of 70 wt%, the peak force of NaOH-treated laminates is 2.14% greater than that of untreated laminates when subjected to low-velocity impact with an energy level of 60 J. However, laminates with low fiber content and without NaOH treatment manifested higher maximum displacement and energy absorption due to the ductile behavior of such materials.