Stainless Steel

Overview of Stainless Steel

Stainless steel, referred to as SS, is an alloy steel with corrosion resistance and rustproof properties. According to the definition in GB/T20878-2007, the main characteristics of stainless steel are its corrosion resistance and rustproof nature, with a chromium content of at least 10.5% and a carbon content not exceeding 1.2% maximum. Stainless steel does not refer to a single steel grade but represents over a hundred industrial stainless steel types, each with specific applications and excellent properties.

Definition of Stainless Steel

Stainless steel is primarily characterized by its corrosion resistance and rustproof nature, with a chromium content of at least 10.5% and a carbon content not exceeding 1.2% maximum. It is a shorthand for stainless and acid-resistant steel, where steel grades that are resistant to weak corrosive media such as air, steam, and water are called stainless steel, while those resistant to chemical corrosive media (acids, alkalis, salts, etc.) are called acid-resistant steel.

Applications of Stainless Steel

  1. Chemical and Food Processing Industries: Used in the manufacture of chemical containers, food processing equipment such as storage tanks, to prevent medium contamination and corrosion, improving production efficiency and equipment service life.
  2. Medical Device Manufacturing: Possessing properties like non-toxicity, odorlessness, and antibacterial qualities, it is suitable for surgical instruments, medical needles, artificial bones, etc.
  3. Architectural Fields: Used in door and window frames, railings, stairway handrails, and other components due to its smooth and aesthetically pleasing surfaces.
  4. Energy and Environmental Protection Industries: Used in the manufacture of nuclear power equipment, solar power generation equipment, and offshore oil and gas drilling platforms due to its corrosion resistance, high temperature resistance, and radiation protection properties.
  5. Electronic Product Manufacturing: Used in the outer shells of mobile phones, tablets, laptops, etc.
  6. Aerospace Industry: Specifically used in the manufacture of aeroengine components and spacecraft structures.
  7. Shipbuilding Industry: Widely used due to its corrosion resistance, lightweight, and strength properties.

Classification of Stainless Steel

  1. Based on Main Chemical Composition: It can be classified into chromium stainless steel, chromium-nickel stainless steel, chromium-manganese-nitrogen stainless steel, etc.
  2. Based on Steel’s Performance Characteristics and Applications: Such as nitric acid-resistant (nitric acid grade) stainless steel, sulfuric acid-resistant stainless steel, etc.
  3. Based on Steel’s Functional Characteristics: Such as low-temperature stainless steel, non-magnetic stainless steel, etc.
  4. Based on Metallographic Structure: It can be classified into austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, etc.

Common Steel Grade Brands of Stainless Steel

Commonly used stainless steel materials in daily life mainly include grades such as 201, 202, 301, 304, 304L, 316, 316L, etc. Categorized by type, commonly used stainless steel mainly includes martensitic stainless steel, ferritic stainless steel, austenitic stainless steel, etc. In addition, there are also nitric acid-resistant stainless steel, sulfuric acid-resistant stainless steel, seawater-resistant stainless steel, and other commonly used steel grades classified by purpose.