粗糙度等级与粗糙度值Ra对照表
粗糙度值Ra
粗糙度等级
um(微米)uin(微英寸) N12502000
N11251000
N1012.5500
N9 6.3250
N8 3.2125
N7 1.663
N60.832
N50.416
N40.28
N30.14
N20.052
N10.0251