Stainless Steel Supplier

Stainless Steel Stockist in India,Stainless Steel Composition,Stainless Steel Properties,Stainless Steel Grades

What is stainless steel?

It is an iron alloy, containing a minimum of 10.5% chromium. Although grades such as 304 and 430 are popular grades, the term ‘stainless steel’ covers a wide variety of metals, each enhanced with various alloying elements to give specific properties such as increased corrosion resistance or improved strength.
Stainless steel has become very popular due to its relatively low cost, aesthetic appearance, high corrosion resistance and low maintenance.

 

What makes it stainless?

Stain’less’ steel is just that…stain’less’ and not stain’never’. The chromium in the stainless steel reacts with the oxygen in the air creating a very thin, protective chromium oxide layer on the surface of the metal. This layer is not visible to the naked eye and protects the surface from corrosion. The layer can be damaged by scratches and sustained exposure to aggressive chemicals, however, because the layer is formed by the reaction of the chromium with air, when the surface is suitably cleaned, the protective chromium oxide layer self-repairs to continue to protect the steel.
Grade 304 (1.4301) is the grade most often used for corrosion resistant reinforcement, suitable for most atmospheric and concrete covered environments.

Grade 316 (1.4401) has a higher molybdenum and nickel content than 304 (1.4301). It is more expensive but also has higher corrosion resistance and is the recommended grade for marine and corrosive environments.

Although the chemical composition and corrosion resistance are different, the physical properties of the 2 grades are similar.
Common grades provided
Stainless Steel is a widely used material across industries because of its corrosion resistance and high versatility. Notably, this tough metal requires relatively low maintenance.

The grades vary depending on the amounts of Carbon, Silicon, Manganese and other elements used in the properties. It is commonly referred to by its grade numbers. We offer a wide range of grades including 301, 303, 304, 304L, 310, 316, 316L, 321, 410, 416, 420, 430 and 440. The grade of steel required depends on your application and use.

We are also able to call upon the unrivalled range of stainless steel products that are available from our extensive warehouses to ensure that we can offer the products that our customers require, no matter how diverse.

As well as our extensive stock range of “standard” products we are also able to offer industry and customer specific services worldwide.

Stainless Steel Types

There are five major types of stainless steel.

Austenitic stainless steels are 200 series or 300 series. They are non magnetic and have high corrosion resistance. They can be hardened only by cold working – not by heat treatment. They are highly formable. But, they are prone to stress corrosion cracking. There are three subtypes: straight, L and H. Popular straight types are grades are 201, 202, 301, 302, 303, 304, 305, 308, 309, 310, 314, 316, 317, 321, 347, 348 and 384. L types have higher corrosion resistance than the straight types. Examples include 304L and 316L. H types are suitable for use in high temperature environments. Austenitic stainless steels are used in shafts, valves, bolts, bushings, nuts, aircraft fittings, chemical equipment, food processing equipment, brewing equipment, cryogenic vessels etc.

Ferritic stainless steels are 400 series. They are magnetic. They have lower ductility and lower corrosion resistance than the austenitic grades. But, they offer high resistance to stress corrosion cracking. They are hardened by cold working and are not heat treatable. Some of the popular grades are 405, 409, 430, 434, 442, 436 and 446. Typical applications are heat exchangers, automotive fasteners, furnace parts, heater parts.

Martensitic stainless steels are 400 series and 500 series. They are magnetic. They have higher strength, higher wear resistance and higher fatigue resistance than the austenitic and ferritic grades. They can also be heat treated. But, corrosion resistance is moderate and lower than the austenitic and ferritic grades. They are highly machinable. Some of the popular grades are 410, 414, 416, 420, 440 and 431. Major applications are machine parts, pump shafts, bolts, bushings, coal chutes, cutlery, hardware, jet engine parts, mining machinery, rifle barrels, screws, valves, aircraft fittings, fire extinguisher inserts, rivets.

Precipitation Hardening Grade Stainless Steels are also called PH types. Their corrosion resistance is equivalent to that of austenitic grades and strength is generally higher than that of martensitic grades. They also retain high strength at elevated temperatures. They are heat treatable. They are mainly used in aerospace industry for aerospace structural components. Popular grades include 17-4PH and 15-5PH.

Duplex stainless steels are mixture of austenitic and ferritic. They provide higher corrosion resistance than the austenitic stainless steels. They are also more resistant to stress corrosion cracking than the austenitic stainless steels. They have higher strength than the austenitic grades. Popular UNS duplex grades include S32101, S32304, S32003, S31803, S32205, S32760, S32750, S32550, S32707 and S33207. Typical applications are water treatment plants and heat exchanger components.