Question

Problem 2. A specimen of medium-carbon steel having an initial diameter ofd, = 0.503 in was tested in tension using a gauge length,-2.0 in . The following data were obtained Elastic region Load (Ibf) 1000 2000 3000 4000 7000 8400 Plastic region Elongation (in) Load (bf 0.0004 0.0006 0.0010 0.0013 0.0023 0.0028 8800 9200 9100 13200 15200 17000 16400 14800 Area (in 0.1984 0.1978 0.1963 0.1924 0.1875 0.1563 0.1307 0.1077 (Use excel or MATLAB to compute stresses and strains, and plot the curves) a) Plot engineering stress - strain diagram. b) Find elastic modulus, 0.2% offset yield strength and ultimate strength of the material (to find some of the results, you might want to zoom on a part of the diagram) c) Is the material ductile or brittle? Explain the reason.

Answer 1

Engineering Shoss- Traumat 」の.ka4 000 O) -A, Lo AL AD L o Tn ela she 3m .frr nule und E, 한 1 for 下 ひん0 3S228.988 5032 L 00IS- '0002 丫ニ 3178555347 lbf. in

Load Elongation strain1 Area strain2 Strain-strain1+strain2 Engg Strain Engg Stress 1000 2000 3000 4000 7000 8400 8800 9200 9100 13200 15200 17000 16400 14800 0.00040.0002 0.0006 0.0003 0.0010.0005 0.0013 0.00065 0.0023 0.00115 0.00280.0014 0.0002 0.0003 0.0005 0.00065 0.00115 0.0014 0.001547379 0.001547379 0.00458544 0.012261844 0.012261844 0.032780665 0.032780665 0.059770667 0.059770667 0.2713179780.271317978 0.5203289980.520328998 0.845004643 0.845004643 0.0002 0.0003 0.0005 0.00065 0.00115 0.0014 00.19840.001547 0 0.1978 0.004585 이 0.1963 0.012262 0 0.19240.032781 이 0.1875 0.059771 0 0.1563 0.271318 01 0.13071 0.520329 01 0.10771 0.845005 5032,712632 10065.42526 15098.1379 20130.85053 5228.98842 42274.78611 44287.87116 46300.95622 45797.68495 66431.80674 76497.23201 85556.11475 82536.48717 74484.14696 0.00458544 Initial Length Initial Area Strain1-elongation/initial length strain2 (Initial area/Final Area)-1 0.198706943

Engg Stress vs Strain plot 90000 80000 70000 60000 50000 40000 30000 20000 10000 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

Lower strain portion data 50000 45000 40000 35000 30000 25000 20000 15000 10000 5000 0012 o.01 0.002 0.004 0.006 0.008 0.01 0.014