What is a universal testing machine How to operate a universal testing machine How mild steel and cast iron behave in tension Mode of failure for mild steel as different than that of cast iron Reason for different modes of failure.
40 grade 12 mm bar must bear 40kN load before yielding (this is calculated based on yielding stress that it must bear i.e. 40000 psi) for 60 grade 12 mm bar it must bear 60kN load before yielding.
I have a concern the stress-strain curve made using a UTM machine differs from the one made using the strain gauges and data logger the reason could be the accounting of global deformation of UTM machine. However, these strain gauges give results usually until the yielding stage and cant capture the post yielding behavior because of large strain. What instrument could we use for this post yield behavior addition to relying on UTM. Also there cant be any correction factor we can calculate and apply to UTM values
First of all we can use an extensometer. Second we can simply take measurement from the displacement ko UTM. Also keep in mind that at the end we only consider the elongation from the central 8 inch portion of an 18-20 inch bar.
Yield Strength must not be less than its grade. E.g. for 40 Grade steel it must be greater than 40,000psi (280MPa) Similarly for 60 Grade steel it must be greater than 60,000psi (420MPa)
