Mitutoyo SURFTEST SJ-410 - Rk (JIS2001, ISO1997, VDA, Free): Enabled-Material-Ratio Roughness (Center Height); Rpk (JIS2001, ISO1997, VDA, Free): Initial Abrasion Height (Peak Height)

No. 99MBB765A
23-32
23.5.29 Rk (JIS2001, ISO1997, VDA, Free): Enabled-material-ratio roughness (center
height)
From the lines that are obtained by selecting 2 points (point A and point B) on the BAC
(material-ratio profile) that differ in mr value by 40%, obtain the line with the smallest
inclination. Set point C and point D to be the points where the obtained line intersects the
lines at mr = 0 and mr = 100. Rk is the difference along the vertical axis (slice level)
between point C and point D.
Rk
23.5.30 Rpk (JIS2001, ISO1997, VDA, Free): Initial abrasion height (peak height)
From the lines that are obtained by selecting 2 points (point A and point B) on the BAC
(material-ratio profile) that differ in mr value by 40%, obtain the line with the smallest
inclination. Set point C and point D to be the points where the obtained line intersects the
lines at mr = 0 and mr = 100. Set point H to the point on the BAC with the same slice level
as point C, and then set point I to the point were the BAC profile and the slice level at mr =
0 intersect. Next, set point J along mr = 0, so that the area enclosed by line segment CH,
line segment CI, and curve HI and the area of triangle CHJ are the same. Rpk is the
distance between point C and point J. (Initial abrasion height)
Rpk
D
G
H
C
A
B
E
A2
A1
Rk
Rvk
Mr1
Mr2
40%
J
F
Rpk
I
Rvk
DEPTH (µm)
mr[c] (%)
D
G
H
C
A
B
E
A2
A1
Rk
Rvk
Mr1
Mr2
40%
J
F
Rpk
I
Rvk
DEPTH (µm)
mr[c] (%)