Comparative analysis of stainless steel bolt materials: 201, 304, and 316

Stainless steel bolts play an important role as connecting components in various industries. Stainless steel bolts made of different materials have different chemical compositions, corrosion resistance, mechanical properties, and applications. This article will compare and analyze stainless steel bolts made of 201, 304, and 316 materials, in order to help readers make more informed decisions when choosing and using them.

1、 Chemical composition

The main components of stainless steel bolts include chromium (Cr), nickel (Ni), and other elements such as manganese (Mn), carbon (C), etc. Stainless steel bolts of different materials have different compositions.

The chemical composition of 201 stainless steel bolts mainly includes 16% -18% chromium and 3.5% -5.5% nickel, in addition to high manganese content. This material belongs to the type with less chromium and nickel in stainless steel.

304 stainless steel bolts contain over 18% chromium and over 8% nickel, with stable composition and high corrosion resistance. 304 stainless steel also contains small amounts of carbon, manganese, and other elements, which make it exhibit good performance in various environments due to its chemical composition.

316 stainless steel bolts add molybdenum (Mo) element on the basis of 304, usually containing 16% -18.5% chromium, 10% -14% nickel, and 2% -3% molybdenum. The addition of molybdenum significantly improves its corrosion resistance, especially in highly corrosive environments.

2、 Corrosion resistance performance

Corrosion resistance is one of the important indicators of stainless steel bolts. Stainless steel bolts of different materials exhibit significant differences in this regard.

201 stainless steel bolts have relatively poor corrosion resistance and are prone to rusting. Its lower chromium and nickel content makes it less resistant to corrosive media such as strong acids and bases, resulting in poor performance in highly corrosive environments.

304 stainless steel bolts have excellent corrosion resistance and can resist common corrosive media such as acid, alkali, etc. It is particularly suitable for use in outdoor environments or humid conditions, such as construction, furniture, and other fields. The corrosion resistance of 304 stainless steel screws gives them a longer service life and higher reliability in these applications.

316 stainless steel bolts have the best corrosion resistance and are suitable for highly corrosive environments. Due to the addition of molybdenum element, it can maintain corrosion resistance under more stringent conditions, such as seawater, chemical industry, etc. 316 stainless steel bolts also exhibit good resistance to atmospheric corrosion and high temperature strength, making them the preferred choice in high demand fields such as pharmaceuticals, aerospace, and marine engineering.

3、 Mechanical performance

Mechanical performance is another important aspect of evaluating the performance of stainless steel bolts. Stainless steel bolts of different materials have differences in strength, wear resistance, and tensile strength.

201 stainless steel bolts have high strength and hardness, but poor ductility. This material is usually suitable for some lighter applications, such as building decoration, kitchen utensils, etc. However, due to its lower ductility, 201 stainless steel bolts may exhibit poor performance when subjected to significant pressure or tension.

The strength and hardness of 304 stainless steel bolts are moderate, with good ductility and plasticity. This enables it to provide stable fastening force in various environments, suitable for most general corrosive environments. 304 stainless steel bolts also have good luster and beautiful appearance, and are commonly used in occasions with high appearance requirements, such as furniture, construction, etc.

316 stainless steel bolts have the highest strength, good wear resistance, and tensile strength. This material has excellent mechanical properties and can withstand significant pressure and tension, making it suitable for high demand fields. 316 stainless steel bolts also exhibit good work hardening properties (non-magnetic), making them advantageous in certain specific applications.

4、 Purpose:

Stainless steel bolts of different materials are suitable for different fields due to their differences in chemical composition, corrosion resistance, and mechanical properties.

201 stainless steel bolts are commonly used in cost sensitive fields such as building decoration and kitchen utensils due to their low cost. Despite its poor corrosion resistance, 201 stainless steel bolts still have practical value in some situations where high corrosion resistance is not required.

304 stainless steel bolts are widely used in industries such as food, chemical, and medical equipment. Due to its excellent corrosion resistance and good mechanical properties, 304 stainless steel bolts perform outstandingly in these fields. In addition, 304 stainless steel bolts are widely used in various decorations and outdoor environments due to their beautiful appearance and rust prevention performance.

316 stainless steel bolts are commonly used in high demand fields such as pharmaceuticals, aerospace, and marine engineering. These fields have high requirements for the corrosion resistance, strength, and high-temperature stability of materials, and 316 stainless steel bolts precisely meet these needs. In addition, 316 stainless steel bolts are also suitable for equipment in seawater, chemical industry, dye, paper, oxalic acid, fertilizer and other production equipment, as well as coastal facilities.

5、 Summary

There are significant differences in the chemical composition, corrosion resistance, mechanical properties, and applications of stainless steel bolts made of 201, 304, and 316 materials. When selecting stainless steel bolts, the appropriate material should be chosen according to the specific application environment and requirements.

201 stainless steel bolts are suitable for cost sensitive situations with low requirements for corrosion resistance; 304 stainless steel bolts are widely used in various fields due to their excellent corrosion resistance and good mechanical properties; 316 stainless steel bolts are suitable for highly corrosive environments and high demand fields.

Understanding the characteristics and advantages of stainless steel bolts made of different materials can help us make more informed choices in practical applications, thereby improving the reliability and safety of connections.