An Investigation of Abrasive Water Jet Machining on Graphite/Glass/Epoxy Composite

Table 5

ANOVA for top and bottom kerf width.

Source	DF	Top kerf width (TKW)				Bottom kerf width (BKW)
		SS	MS		% SS	SS	MS		% SS
Pressure ()	2	0.07027	0.03514	14.08	24.72	0.04636	0.02318	9.14	19.68
Feed rate ()	2	0.03521	0.01761	7.05	12.38	0.03609	0.01805	7.12	15.31
Abrasive concentration ()	2	0.00054	0.00027	0.11	0.19	0.00084	0.00042	0.17	0.35
SOD ()	2	0.14829	0.07415	29.70	52.16	0.10588	0.05294	20.87	44.92
	4	0.00368	0.00092	0.37	1.29	0.01212	0.01215	1.19	5.14
	4	0.00481	0.00537	0.48	1.68	0.00618	0.00618	0.61	2.62
	4	0.02149	0.00121	1.40	7.55	0.01299	0.01299	1.28	5.15
Error	6	0.01497	0.00249	—	5.13	0.01521	0.00253	—	6.45

DF: degree of freedom, MS: mean square, SS: sum of square, and % SS: percentage contribution.