Materials Engineering Lab

Lab # 3 – Cold Rolling and Microstructural Change

Objective: The main objective of the present test is to determine the microstructure and hardness changes after the cold rolling process.

Apparatus: Cold rolling unit

Cutter, belt and rotary grinder, polisher, etchant and optical microscope

Vickers hardness unit

Materials: Cold rolled Al alloy samples

Procedures: Cold rolling is a process of compressing and squeezing of sheet metals or strip stocks between two oppositely rotating rollers to get thinner materials, such as Al foil and Cu sheets. The amount of strain introduced to the metals will determine the hardness and other material properties of the cold rolled products. Generally, cold rolling increases the yield strength and hardness values by introducing defects into the crystals structures of the metals. Since the temperature of the metal is below its recrystallization temperature or room temperature, this process is called cold rolling process.