Rolling is the process of reducing the thickness or changing the cross section of a
long workpiece by compressive forces applied through a set of rolls (Fig. 13.1).
This process is similar to rolling dough with a rolling pin to reduce its thickness.
Rolling, which accounts for about 90% of all metals produced by metalworking
processes, was first developed in the late 1500s. Modern steelmaking practices and
the production of various ferrous and nonferrous metals and alloys now generally
involve combining continuous casting with rolling processes. This greatly improves
productivity and lowers production costs, as described in Section 5.4. Nonmetallic
materials also are rolled to reduce their thickness and enhance their properties.
Typical applications are in the rolling of plastics, powder metals, ceramic slurry,
and hot glass.