The Impact Toughness and Hardness of Treated and Untreated Sisal Fibre-Epoxy Resin Composites

Table 2

Barcol values of hardness for pure epoxy resin and treated and untreated sisal fibre-epoxy resin composites.

Weight % of the reinforcing fibre	Values of hardness for the untreated sisal fibre-epoxy resin composites (Barcol units-BU)			Values of hardness for the treated sisal fibre-epoxy resin composites (Barcol units-BU)
	Range (BU)	Average (BU)	Coefficient of variation (%)	Range (BU)	Average (BU)	Coefficient of variation (%)
Epoxy (0)	25.00–27.00	26.00 ± 0.94	3.63	25.00–27.00	26.00 ± 0.94	3.63
5	27.00–31.00	29.00 ± 1.41	4.88	29.00–31.00	30.00 ± 0.94	3.14
10	29.00–31.00	30.00 ± 0.82	2.72	37.00–39.00	38.00 ± 0.82	2.15
15	27.00–31.00	29.00 ± 1.49	5.14	27.00–31.00	29.00 ± 1.56	5.39
30	38.00–41.00	39.00 ± 1.77	3.46	42.00–46.00	43.00 ± 1.43	3.54
50	44.00–47.00	45.00 ± 1.65	4.35	48.00–51.00	49.00 ± 1.32	3.26