— Mild steels or low carbon steels may be classified as follows:
(i) Dead mild steel — C 0.05 to 0.15%.
Dead mild steel is used for making steel wire, sheets, rivets, screws, pipe, nail and chain.
It has a tensile strength of 390 N/mm2 and a hardness of about 115 BHN.
(ii) Mild steel containing 0.15 to 0.20% carbon has a tensile strength of 420 N/mm2 and hardness 125 BHN.
It is used for making camshafts, sheets and strips for fan blades, welded tubing, forgings, drag lines etc.
(iii) Mild steel containing 0.20 to 0.30% carbon has a tensile strength of 555 N/mm2 and a hardness of 140 BHN.
It is used for making valves, gears, crankshafts, connecting rods, railway axles, fish plates, small forgings etc.