Tribological behaviour of injection moulded PLA/β-TCP biocomposites

This study aims to develop a PLA based bio composites reinforced with β-TCP with different proportions of 5, 10 and 15 wt%, that can enhance the tribological capabilities. Pin-on-disc tests were conducted to evaluate wear rates and coefficients of friction (CoF). PLA/β-TCP samples were fabricated using injection moulding process and their tribological behaviour was investigated in this study. The worn surface was investigated using scanning electron microscopy (SEM) and 3D surface roughness test. Results showed that β-TCP greatly affected the wear performance of the PLA matrix. Results reveal that adding 5 wt% of β-TCP the wear resistance enhanced considerably at 10 N load and 100 rpm speed of spindle, whereas the reduction of CoF owing to proper filler distribution and increase in load transfer to 20 N and 200 rpm speed in the composite. Also, by increasing the filler amount (to 10 wt%), the wear rate and CoF also increases, moreover reduction in wear rate and CoF was observed when the load and spindle speed reaches the maximum of 30 N and 300 rpm. The surface morphology shows that PLA was prone to adhesive wear while composites suffered more from abrasive wear. This difference in wear can be explained by the formation of agglomerates, debonding and abrasion at the filler/matrix interface, causing abrasive and third-body wear. The wear performance of sample P95/C5 exhibited a significant enhancement by 95% reduction in wear loss compared with pure PLA.