Comparative Analysis of Stainless Steel Bolt Materials: 201, 304 and 316

Stainless steel bolts, as connecting elements, play an important role in various industries. Stainless steel bolts of different materials have different chemical compositions, corrosion resistance properties, mechanical properties and applications. This article will compare and analyze the stainless steel bolts of three materials: 201, 304 and 316, so that readers can make more informed decisions when choosing and using them.

I. 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 differ in composition.

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

The chemical composition of 304 stainless steel bolts contains more than 18% chromium and more than 8% nickel, with a stable composition and high corrosion resistance. 304 stainless steel also contains a small amount of carbon, manganese and other elements, and this chemical composition enables it to exhibit good performance in various environments.

The chemical composition of 316 stainless steel bolts add a molybdenum (Mo) element on the basis of 304, and usually contain 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.

II. Corrosion Resistance

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

The corrosion resistance of 201 stainless steel bolts is relatively poor and they are prone to rusting. Their lower chromium and nickel content results in a lower resistance to corrosive media such as strong acids and alkalis, and thus they perform poorly in highly corrosive environments.

The corrosion resistance of 304 stainless steel bolts has excellent corrosion resistance and can resist common corrosive media such as acids and alkalis. It is particularly suitable for use in outdoor environments or humid conditions, such as in the fields of construction and furniture. The corrosion resistance of 304 stainless steel screws gives them a long service life and high reliability in these applications.

The corrosion resistance of 316 stainless steel bolts is the best and they are suitable for highly corrosive environments. Due to the addition of the molybdenum element, they can maintain their corrosion resistance under more severe conditions, such as in seawater and the chemical industry. 316 stainless steel bolts also show good atmospheric corrosion resistance and high-temperature strength, making them the first choice for high-demand fields such as pharmaceuticals, aerospace and marine engineering.

III. Mechanical Properties

Mechanical properties are another important aspect for evaluating the performance of stainless steel bolts. Stainless steel bolts of different materials differ in strength, wear resistance, tensile resistance, etc.

201 stainless steel bolts have high strength and hardness but poor ductility. This material is usually suitable for some lighter application scenarios, such as building decoration and kitchen utensils. However, due to its lower ductility, 201 stainless steel bolts may exhibit poor performance when subjected to large pressures or tensions.

304 stainless steel bolts have moderate strength and hardness and good ductility and plasticity. This enables them to provide a stable tightening force in various environments and is suitable for most general corrosive environments. 304 stainless steel bolts also have a good luster and an elegant appearance and are often used in occasions where a high appearance requirement is imposed, such as furniture and building.

316 stainless steel bolts have the highest strength, good wear resistance and tensile resistance. This material has excellent mechanical properties and can withstand large pressures and tensions, suitable for high-demand fields. 316 stainless steel bolts also show good work hardening (non-magnetic), giving them an advantage in some specific applications.

IV. Uses

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

201 stainless steel bolts are mostly used in cost-sensitive fields such as building decoration and kitchen utensils because of their lower cost. Although their corrosion resistance is poor, 201 stainless steel bolts still have application value in some occasions where the corrosion resistance requirement is not high.

304 stainless steel bolts are widely used in industries such as food, chemical and medical devices. Due to their excellent corrosion resistance and good mechanical properties, 304 stainless steel bolts perform well in these fields. In addition, 304 stainless steel bolts are also widely used in various decorative and outdoor environments because of their beautiful appearance and anti-rust properties.

316 stainless steel bolts are often used in high-demand fields such as pharmaceuticals, aerospace and marine engineering. These fields have high requirements for the material's corrosion resistance, strength and high-temperature stability, and 316 stainless steel bolts meet these requirements. In addition, 316 stainless steel bolts are also suitable for equipment in seawater, chemical industry, dyes, paper making, oxalic acid, fertilizer production equipment and facilities in coastal areas.

V. Summary

The stainless steel bolts of 201, 304 and 316 materials have significant differences in chemical composition, corrosion resistance properties, mechanical properties and uses. When choosing stainless steel bolts, the appropriate material should be selected according to the specific application environment and requirements.

201 stainless steel bolts are suitable for cost-sensitive and corrosion resistance requirement is not high occasions; 304 stainless steel bolts are widely used in many 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 of different materials helps us make more informed choices in practical applications, thus improving the reliability and safety of connections.