Mitutoyo HR-530 Series - Precautions for the Rockwell;Rockwell Superficial Hardness Test

No. 99MBG518A
A-10
PART A : 4 Hardness Test Methods
■FigureoftheprincipleofRockwellhardnessandRockwellsupercial
hardness
7
1
F
0
F
0
+F
1
8
7
F
0
5
6
2
4
3
7
Y
X
RockwellhardnessorRockwellsupercialhardness=
h
S
N –
X: Time 4: Depth of permanent indent h
Y: Position of indenter 5: Specimen surface
1: Depth of indent with preliminary test force F
0
6: Reference surface for measuring the depth
of permanent indent
2: Depth of indent with additional test force F
1
3: Elastic recovery after eliminating additional
test force F
1
7: Position of indenter
8: Curve of indent depth and time
4.1.2 PrecautionsfortheRockwell/RockwellSupercialHardness
Test
■Test surface
Thetestsurfaceshouldbeaatsurfaceatarightangletothedirectionofthetestforce.Unlessthe
standardfortheproductormaterialspeciesotherwise,thetestsurfaceshouldbesmoothwithout
roughness,withnooxidelm,foreignsubstanceandparticularlynolubricantapplied.
■Distance to the edge of the specimen from the center of the indent
The distance between the center points of two adjacent indents needs to be at least three times the
indent diameter. The distance from the center point of the indent to the edge of the specimen should be
at least two and a half times the indent diameter.