PROPERTIES OF ENGINEERING MATERIALS SYMBOLS5;6 a Aj Af A0 Ar Bhn d D E f" f F G HB lf lj l0 Q RB RC area of cross section, m2 (in2 )Ã original area of cross section of test specimen, mm2 (in2 ) area of smallest cross section of test specimen under load Fj , m2 (in2 ) minimum area of cross section of test specimen at fracture, m2 (in2 ) original area of cross section of test specimen, m2 (in2 ) percent reduction in area that occurs in standard test specimen Brinell hardness number diameter of indentation, mm diameter. | Source MACHINE DESIGN DATABOOK CHAPTER 1 PROPERTIES OF ENGINEERING MATERIALS SYMBOLS5 6 a area of cross section m2 in2 original area of cross section of test specimen mm2 in2 A area of smallest cross section of test specimen under load F m2 in2 2 Af minimum area of cross section of test specimen at fracture m2 in2 2 2 Ao Ar original area of cross section of test specimen m2 in2 percent reduction in area that occurs in standard test specimen Bhn d Brinell hardness number diameter of indentation mm diameter of test specimen at necking m in D E diameter of steel ball mm modulus of elasticity or Young s modulus GPa Mpsi Mlb in2 f f F G strain fringe fri value pm fri pin fri stress fringe value kN m fri lbf in fri load also with subscripts kN lbf modulus of rigidity or torsional or shear modulus GPa Mpsi Hb lf j Brinell hardness number final length of test specimen at fracture mm in gauge length of test specimen corresponding to load F mm in ko Q Rb Rc v a original gauge length of test specimen mm in figure of merit fri m fri in Rockwell B hardness number Rockwell C hardness number Poisson s ratio normal stress MPa psi The units in parentheses are US Customary units . fps foot-pounds-second . Downloaded from Digital Engineering Library @ McGraw-Hill Copyright 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PROPERTIES OF ENGINEERING MATERIALS CHAPTER ONE ab - Cs f - transverse bending stress MPa psi compressive stress MPa psi strength MPa psi tensile stress MPa psi endurance limit MPa psi endurance limit of rotating beam specimen or R R Moore endurance limit MPa psi f sfb Cs c asu b uc ut CT-su suc sut yc yt syc asyt endurance limit for reversed axial loading MPa psi endurance limit for reversed bending MPa psi compressive strength MPa psi tensile strength MPa psi ultimate stress MPa psi ultimate compressive stress MPa psi ultimate tensile stress MPt psi .