Question: Medium carbon steels (0.25-0.50 wt%C) are commonly chosen for axles, crankshafts, gears, couplings, etc. The highest strengths achievable for medium carbon steels usually require quenching and tempering. Hardenability is the ease with which martensite can be formed during quenching, which leads to the achievement of high strength by quenching and tempering. The addition of alloying elements in low alloy steels improves the hardenability for thicker sections of steel, but this also strongly affects weldability due to the potential to form martensite when it is not wanted. This assignment will show how the concepts of phase equilibrium, kinetics, and microstructure can be used explain the differences between certain steel grades in terms of phase evolution during heat treatment. Need Assignment Help?