In order to avoid excess deformation of the indenting

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In order to avoid excess deformation of the indenting ball we were advised not use it on steel that exceeded hardness of over 444 HB, so we technically assumed that our sample steel had a hardness of below that value. This also in line with the Brinell hardness test as it is not recommended to be performed on material of hardness greater than 627 HB. An equivalent test we could have used is the Rockwell test
which determines hardness by measuring the depth of penetration of an indenter under a large load compared to the penetration made by a preload.Procedures:1.Place the sample on the lower adapter of the Hydraulic Pump.2.Ensure it makes contact with the indenter at a point not too near to edge or center.3.Apply the testing load specific to the sample for 15 seconds, 10000N for steel and 5000Nfor aluminum.4.Remove the load and measure the average diameter of the indentation using microscope given.5.Repeat steps 1-4 twice more and ensure the indentations are satisfactorily distanced from one another.Results:Table of collected Data:SAMPLENo. ofTrialBallDiameter,D(mm)Diameter of impression, d(mm)Load, Pdxdyd =0.5(dx+ dy)inNEWTON(N)in Kg(N/9.81)Steel110.002.902.752.825102231042.122.922.852.88599451013.7632.902.852.875102411054.13Aluminum110.002.352.52.4254970506.62522.42.52.455035513.2532.42.452.4255021511.82
Table of calculated Data:SAMPLENo. ofTrialDepth ofIndentation,Area ofIndentation,BrinellHardnessAverageBrinellSteel10.2046.398162.872157.86820.2136.679151.78330.2116.632158.951Aluminum10.1494.689108.055108.14320.1524.787107.21130.1494.668109.164Sample Calculations for Aluminum sample #1:d = (dx + dy)/2d = (2.35mm+2.5mm)/2d = 2.425mmt=(D(D2d2)12)2t=(10mm((10mm)2−(2.425mm)2)12)2t = 0.149 mmA=πD tA=π(10mm)(0.149mm)A = 4.689mm2
HB=P(kg)A(mm2)Load(N) = 4970NLoad(Kg) = 4970N/(9.81m/s2) = 506.626 (Kg) = PHB=506.626(kg)4.689(mm2)HB = kg/mm108.055¿2)Discussion:

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