Quick Guide to Precision Measuring Instruments

67/76

PG65Quick Guide to MeasurementHRDHRCHRARockwell hardness1.80.11020304050607080901000.20.30.40.50.60.70.80.91.01.11.21.31.41.51.61.7Minimum thickness of specimen (mm)15N30N15T45N30T45T0.01020304050607080901000.20.40.60.81.01.21.4HRTHRNMinimum thickness of specimen (mm)Rockwell hardnessHRHHREHRFHRKHRGHRRockwell hardnessB3.30.7520304050607080901000.91.051.21.351.51.651.81.952.12.252.42.552.72.8533.15Minimum thickness of specimen (mm)HV=0.1891t>1.5dh≒d/7t: Thickness of specimen (mm)d: Diagonal length (mm)h: Depth of indentation (mm)[Example]Specimen thickness t: 0.15mmSpecimen hardness: 185HV1Test force F: 9.807N (1kgf)Diagonal length d: 0.1mmFd2dthVickers hardnessHV200010005003002001005030200.0010.0020.0030.0050.010.020.030.050.10.20.30.51230.0010.0020.0030.0050.010.020.030.050.10.20.30.512t:mm d:mm0.0010.0020.0030.0050.010.020.030.050.10.20.30.51235102030504.903x10-3Test forceF:NHardness symbolF:kgfMinimum thickness of specimenDiagonal length of indentation9.807x10-319.61x10-329.42x10-349.03x10-398.07x10-30.19610.29420.49030.98071.9612.9424.9039.80719.6129.4249.0398.07196.1294.2490.3Relationship between Vickers Hardness and the Minimum Thickness of a SpecimenRockwell Hardness ScalesRockwell Supercial Hardness ScalesRelationship between Rockwell/Rockwell Supercial Hardness and the Minimum Thickness of a SpecimenScaleIndenterTest force (N)Application15NDiamond147.1Carburizing, nitriding, etc.Thin surface hardened layer of steel30N294.245N441.315TBall with adiameter of1.5875mm147.1Mild steel, brass, thin sheet of bronze, etc.30T294.245T441.315WBall with adiameter of3.175mm147.1Plastic, zinc, bearing alloy30W294.245W441.315XBall with adiameter of6.35mm147.1Plastic, zinc, bearing alloy30X294.245X441.315YBall with adiameter of12.7mm147.1Plastic, zinc, bearing alloy30Y294.245Y441.3ScaleIndenterTest force (N)ApplicationADiamond588.4Cemented carbide, thin steel sheetHardened steelSteel (100HRB more ~70HRC below)D980.7C1471FBall with adiameter of1.5875mm588.4Bearing metal, annealed copper brassHard aluminum alloy, beryllium copper, phosphor bronzeB980.7G1471HBall with adiameter of3.175mm588.4Bearing metal, the grinding wheelBearing metalBearing metalE980.7K1471LBall with adiameter of6.35mm588.4Plastic, leadM980.7P1471RBall with adiameter of12.7mm588.4plasticS980.7V1471