A specimen of 1040 carbon steel has a length 2 m Its round c

A specimen of 1040 carbon steel has a length 2 m. Its round cross section has a radius 1 cm. A tentile load of 150,000 N is applied to the specimen. What is the tensile stress of the specimen With a 150,000 N tensile load, does the specimen have any plastic deformation? Explain why. With a 150,000 N tensile load, what will be the final length of the specimen? With a 150,000 N tensile load, what will be the final radius of the specimen? What is the maximum tensile load that can be permitted without producing plastic deformation on specimen? When the specimen breaks under tension load, what is its length?

Solution

a. Stress = force/area = 150000/(pi * .01 * .01) = 47,74,64,829 N/m2

b. Yield stress is at 420 MPa so yes this would face plastic deformation.

c. Young\'s modulus = 200GPa . Therefore Strain = Stress/Young\'s Modulus = 0.002. So total length = 2*(1.002) = 2.004 m
d. Volume remains constant . therefore 2*(pi* .01*.01) = 2.004*(pi* r^2). So r = 0.0099 m = 0.99 cm
e. 420 MPa is the max tensile strength for no plastic deformation. See: http://www.azom.com/article.aspx?ArticleID=6525#4
f. Exact length can only be obtained through experiments. It will certainly be greater than 2