Mild steel (hot rolled bars) has a apparent yield point, before clear signs of the destruction (large deformation, elongation) is a ductile failure.

Mechanical properties of hard steel pipe Hard steel (heat treatment of steel and high strength steel wire) is with high strength, but poor plasticity, and brittleness. From the load to suddenly pull off, virtually non-existent yield phase (flow increase). Is a brittle failure. Cold drawn and hot rolled bars are mild steel. Hard steel and mild steel is according to whether they exist division of the yield point, because hard steel has no significant yield point and plastic compared with mild steel, its control stress factor is lower than mild steel. Mild Steel (MS) pipes are manufactured using low carbon (less than 0.25%) steel. Due to low carbon content the pipes do not harden and are easy to use. As MS Pipes are made from mild steel they can easily be welded and formed in various shapes and sizes for pipelining and tubing purposes. These are generally used for drinking water supply i.e. Plumbing, Firefighting, HVAC but can also be used in various other Industrial and Engineering applications. These pipes are usually coated with other metals/paints/varnish etc to prevent it from rusting but extra care should be taken to prevent it under extreme conditions.