Wear, morphological and thermal behavior of flax fibre reinforced epoxy composites

Abstract

Effect of different types of chemical treatments, viz. alkali (NaOH) treatment, trimethoxymethylsilane(Silane) treatment, and combination of both alkali and silane treatment on structural and thermal properties of flax fibres has been investigated by means of scanning electron microscopy (SEM), X-Ray diffraction and thermogravimetric (TGA) analysis. Besides, flax fibre reinforced epoxy composites (FFRECs) comprising 45wt.% of fibre reinforcement have been subjected to multi-pass dry sliding wear test and experimental runs are conducted as per Taguchi design of experiment technique. Crystallinity index (CI) value of 54.85 is found for alkali-cum-silane (AST) treated fibre, which is 39.23 % and 29.79 % higher than that of untreated (UT) fibre and silane treated (ST) fibre respectively. However, a very mere difference in CI values is observed between alkali treated (AT) and AST fibres. TGA study shows that UT fibre is thermally stable up to 240°C and this stability is enhanced to 310°C owing to chemical alteration as exhibited by AST fibre. Microhardness test indicates minor improvement in the hardness property of the treated FFRECs over the untreated composites. Wear test results reveal that chemically modified FFRECs offer better wear resistance than untreated FFRECs and the mechanisms endured by the composites are exposed by SEM. Amongst the prepared FFRECs, silane-treated FFREC exhibits better wear resistance property. Furthermore, the findings of analysis of variance (ANOVA) show that applied load and sliding distance contribute significantly to wear volume loss of FFRECs.