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A According to metallurgical theory, the recrystallization temperature of different metal materials is vary. The following table summarizes the lowest recrystallization temperature:

Metal	Lowest recrystallization temperature (°C)
Iron (Fe)	360~450
Copper (Cu)	200~270
Aluminium (Al)	100~150
Tin (Sn)	0
Lead (Pb)	0
Tungsten (W)	1200

Based on the data in the table, the forming processes for tin and lead, which have recrystallization temperatures of 0°C, cannot be classified as cold forging, but rather as hot forging. In contrast, the forming of iron, copper, and aluminum at room temperature can be considered cold forging.

A Cold heading is a pressure processing that involves little or no cutting of the metal. It is a metalworking process that creates plastic deformation of the metal using molds - typically consisting of a male die (such as a punch) and a female die (like a heading die) - under the influence of external force. The process typically produces the required parts or blanks. Cold heading is ideal for the production of bolts, screws, nuts, rivets, pins and other standard fasteners.

A A header die is a fundamental tool of cold forming process. It is used to shape the screw head and includes various types such as carbide heading dies, shearing dies, die cutting blades, screw first punch die, screw second punch die, as well as pins. Moreover, the selection of the materials for the header die is crucial, as its service life depends significantly on the quality of the tungsten steel used.