Cold rolled steel is essentially hot rolled steel that has had further processing. The steel is processed further in cold reduction mills, where the material is cooled (at room temperature) followed by annealing and/or tempers rolling. This process will produce steel with closer dimensional tolerances and a wider range of surface finishes.
Application  Automobiles, electrical appliances, pipes, containers, furniture, parts, etc.

Hot rolling is a mill process which involves rolling the steel at a high temperature (typically at a temperature over 1700° F), which is above the steel’s recrystallization temperature. When steel is above the recrystallization temperature, it can be shaped and formed easily. Hot rolled steel is typically cheaper than cold rolled steel due to the fact that it is often manufactured without any delays in the process, and therefore the reheating of the steel is not required (as it is with cold rolled).

Application Automobiles, electrical appliances, pipes, containers, furniture, parts, etc.

Galvannealed (or galvanneal) Steel is a carbon steel sheet coated with zinc on both sides by the continuous hot-dip process. Immediately as the strip exits the coating bath, the molten zinc coating is subjected to an in-line heat treatment that converts the entire coating to a zinc-iron alloy. (The iron diffuses from the steel into the coating.) The galvannealed surface has a non-spangled matte finish, a finish very different than the highly metallic appearance of the galvanized coating. At times, the galvannealed coating may appear similar to uncoated cold rolled steel. One of the primary attributes of the galvannealed coating is that the surface accepts paint very readily. It can be painted without the application of a pretreatment, although a pretreatment will enhance the performance after painting.

Application Automobile, electrical appliance and etc.

This material has a zinc coating applied to sheets of steel through a process called “continuous hot-dip,” in which steel sheet passes through a bath of molten zinc. The liquid zinc bonds to the iron in the steel forming a protective layer on both sides of the sheet. The steel sheet can then be spun into a finished part because the zinc coating does not flake or peeling off during the metal spinning process. The finished part resists corrosion without any additional or secondary painting or coating, making galvanized spinning the most economical process for protecting steel from corrosion.

Application Material is used for manufacturing electrical appliance, automobile, construction material and etc.

Type		Designation
Commercial		SGHC
Drawing	340N-class	SGH340
	400N-class	SGH400
	440N-class	SGH440
	490N-class	SGH490
	540N-class	SGH540

Type		Designation
Commercial		SGCC
Drawing	Grade1	SGCD1
	Grade2	SGCD2
	Grade3	SGCD3
	Grade4(non aging property)	SGCD4
Structural	340N-class	SGC340
	400N-class	SGC400
	440N-class	SGC440
	490N-class	SGC490
	570N-class	SGC570
Commercial,hard		SGCH

A pre-painted (or pre-coated) steel sheet is a steel sheet having paint layers applied before shipment. This painting brings them various advantages such as solution of the problems related to volatile organic compounds and utilization of plant areas of the painting work for other purposes.

Application Home appliances, building materials

The process of electrogalvanizing involves electroplating, running a current of electricity through a saline/zinc solution with a zinc anode and steel conductor. Compared to hot dip galvanizing, electroplated zinc offers these significant advantages:

– Smooth, attractive surface produced by electro-plating.
– Formability of coating is excellent, with same mechanical properties as base metal. Weldability is also good due to light coating.
– Paintability, anti-fingerprint property and lubricity can be added by post-treatment.

Application automobiles, electrical appliances

Silicon steel is the most important soft magnetic material in use nowadays. 

 

Applications vary from small relays or pulse transformers to tons used in generators, motors, and transformers. Silicon steel is used to decrease wasteful dissipation of energy in electrical apparatus and to minimize the physical dimensions of the increasingly powerful equipment.

Application

Silicon steel is the most important magnetic material in industrial applications. The general applications include volt relays or pulse transformers from the generator, automotive, and transformer sectors.