Table 4.

Basic surface roughness parameters of AW-5251 aluminium alloy sheets.

Temper Type	Sa, µm	Sv, µm	Sp, µm	Sku	Ssk
O	0.302	1.39	0.37	3.48	0.267
H14	0.340	1.62	2.48	3.34	0.298
H16	0.362	2.08	2.98	3.67	0.338
H22	0.325	1.53	2.04	3.58	0.321