Pencil Hardness - A physical measurement of the hardness of a paint film which is based on the resistance of the film to cut-through by pencil leads of specified hardness. Pencil hardness values range between 2B and 5H.

Physical Properties - Those properties familiarly discussed in physics, exclusive of those described under mechanical properties; for example: density, electrical conductivity and coefficient of thermal expansion.

Pickling - The process of removing hot rolled mill scale from billets, bars or hot rolled sheets with sulphuric or hydrochloric acid. The scale is removed for hot rolled pickled                   and oiled sheets or for further processing of the hot rolled steel product into cold drawn bars and wire and cold rolled sheets and strip.

Plastic Deformation - Deformation of a material that will remain permanent after removal of the load that caused it.

Precipitation Hardening - A process of hardening an alloy in which a constituent precipitates from a supersaturated solid solution. This process is used for non-ferrous alloys to change the mechanical properties of the metal and is also called aging or age hardening.

Prelubricant - An oil coating that is applied to steel sheet to enhance formability (deep drawing). This lubricant is usually applied when the customer wishes to avoid the application of a forming lubricant in his plant.

Pressure Vessel Steel (PVS) - Product intended for pressure vessels and similar end use applications.

Primer Coat - The base coat of paint in a typical two-coat system. Primer coats are usually applied to produce a dry film thickness of approximately 0.2 mil.

Proportional Limit - Same as elastic limit.