Worksheet #2 solutions Aug. 30, 2007 (a) The elongation at 0.2% strain is δ f = 0 . 002 × 200 mm = 0 . 4 mm Draw a line parallel to the elastic loading line, starting from point (0.4mm,0kN). Measure the y cordinate of the intersection point of this line and the load line, we get: load F ≈ 36 kN This is the force associated with the 0.2% oFset yield stress. The yield stress is then S y = F A0 = 36 , 000 N π (0 . 007 m ) 2 = 230 MPa (b) Get the ultimate tensile strength, by measuring the second ±gure, the maximum load is about 65 kN , so the ultimate tensile strength is: S u = F max A0 = 65 , 000 N π (0 . 007 m ) 2 = 420 MPa (c) To get elastic modulus, by measuring the elastic loading line, we get
This is the end of the preview. Sign up
access the rest of the document.