What is Stainless Steel Alloy?

0 0 votes

Stainless Steel Alloy: An Overview

Stainless steel is a steel alloy with a chromium content of 10.5% with or without alloying elements and composes a maximum of 1.2% carbon by mass. Also termed as inox steel, stainless steel is so-called as it does not stain, rust, or corrode – hence ‘Stainless Steel.’ Stainless steelis majorly known for its corrosion resistance that can be altered with increasing chromium content.

Owing to its excellent oxidation resistance, high durability, excellent ductility, and lustrous appearance, stainless steel is gaining momentum in a wide variety of industries.

Also called ‘green material,’ stainless steel is 100% recyclable, adding to its applications catering to the community with eco-friendly nature and reasonable rates.

Research states India is the second-fastest-growing market for stainless steel, and boosting its demand is the emergence of heavy industries in India that use steel as their major raw material in manufacturing and large-scale operations.

Types of Stainless Steel Alloys

Stainless steel alloy is a mix of Iron and Chromium, including other components depending on the requirement or the application it is being used for.

While stainless must contain at least 10.5% chromium, the exact components and their ratios will vary depending upon the grade requested and the intended use of the stainless steel.

There are various grades of stainless steel with varying molybdenum and chromium content with varying crystallographic structures to suit the various environments.

Broadly stainless steel comes in 5 different categories:

  • Ferritic Stainless Steel: 

Graded as 400 series, the ferritic class of stainless steel contains carbon in low levels with higher chromium content from 10.50 to 30.00%. They are called ferritic alloys as they contain primarily ferritic microstructures at all temperatures and can’t be hardened through heat treating and quenching.

  • Austenitic Stainless Steel: 

Austenitic stainless steel contains Chromium between 16-25%, and nitrogen, giving it excellent corrosion resistance. Classified with 200-300 stainless steel series, the 300-series grades are chromium-nickel alloys, and the 200-series signify a set of compositions in which manganese or nitrogen replace some of the nickel.

  • Martensitic Stainless Steel: 

Similar to ferritic steel, martensitic stainless steel has higher carbon contents up to 1%. They contain 12-14% chromium, 0.2-1% molybdenum, and no significant amount of nickel. A common martensitic stainless is AISI 440C, comprising around 16 to 18% chromium and 0.95 to 1.2% carbon.

  • Duplex Stainless Steel: 

As the name indicates, duplex stainless steel combines two of the main stainless steel alloy types – austenitic and ferritic. They have a mixed microstructure of both austenite and ferrite with the aim usually being to produce a 50:50 mix and in commercial alloys, the ratio may be 40:60.

  • PH Stainless Steel: 

PH stainless steel comprises around 17% chromium and 4% nickel. These steels develop high strength owing to additions of aluminum, titanium, niobium, vanadium, or nitrogen, which form coherent intermetallic precipitates in a heat treatment process called – heat aging.

Properties of Stainless Steel

  • Corrosion-resistant

  • High tensile strength

  • Very durable

  • Temperature resistant

  • Easy formability and fabrication

  • Low-maintenance (long-lasting)

  • Attractive appearance

  • Environmentally friendly (recyclable)

Applications of Stainless Steel 

Stainless steel is a functional dynamic possessing all the great qualities that a desirable industry material has. It offers excellent resistance to corrosion with a high tensile strength that makes it one of the most widely used materials in multifarious industries.

  • It is the material of choice in transportation and processing equipment, engine parts, and firearms.

  • Used in chemical and power engineering industries, as nuclear reactor vessels, heat exchangers, and more.

  • Stainless steel does not need painting or coating, which makes them suitable for use in applications where cleanliness is required like – in cookware, cutlery, and surgical instruments.

Reasons for the Growing Demand for Stainless Steel Alloys

  • Strength

Strength is a fundamental property of stainless steel, giving it an edge over other materials. It remains potentially strong at extremely high or low temperatures, making it a highly sought-after metal for demand applications, including aviation.

  • Easy to clean

Easy to clean makes it the most hygienic material, impacting its use in catering and medical applications. It restricts the growth of bacteria, being easy to clean and sterilize.

  • Aesthetics

Strength is not the only property of stainless steel. Its shiny luster looks great, encouraging its use in architecture. It adds a contemporary look to classic and modern spaces without compromising their functionality.

  • Corrosion resistance

Being highly resistant to corrosion, stainless steel can fend off rust and water stains. This resistant behavior of stainless steel comes from the addition of Chromium to the metal, which, when exposed to oxygen, creates a fine film over the steel to protect it.

We are a comprehensive marketplace for stainless steel and stainless steel products. Offering excellent quality stainless steel – ISO certified and graded by top grading agencies of India, we are a leading manufacturer of high-quality stainless steel. Endeavoring to curb the dependence on foreign imports, we toil to create great functional products that are – made in India.

Notify of

Inline Feedbacks
View all comments