1 Carbon Steel Currently, the most used material in the fastener industry is carbon steel because of its high plasticity and its relative low cost compared to other materials.
Carbon steel can be divided into ultra low carbon steel, low carbon mild steel, low carbon steel, medium carbon steel, and high carbon steel according to the level of carbon content.
Ultra-low carbon steel, tail hole pot nail material.
Low carbon mild steel for general screws that do not require heat treatment (hardening), strength class 3.6
Low carbon steel, for general screws that do not require heat treatment (hardening), strength class 4.8
Medium carbon steel, for general screws without special mechanical properties, strength class 8.8
High-carbon steel, generally not used for fastener production
2 Stainless steel Stainless steel is usually classified according to the state of organization: austenitic steel, martensitic steel, ferritic steel
Austenite (18% Cr, 8% Ni) contains more than 18% chromium, and also contains about 8% nickel and a small amount of molybdenum, titanium, and nitrogen. Good overall performance, resistance to many media corrosion, such steel has good plasticity, toughness, weldability and corrosion resistance.
Ferritic stainless steels have high corrosion resistance and oxidation resistance because of their high chromium content, but they have poor mechanical and process properties. Brittleness occurs when the ferritic stainless steels exceed 400°C. Therefore, they are often used in household appliances and accessories.
Martensite martensite (13%Cr) has higher strength, hardness and wear resistance due to its higher carbon content, but its corrosion resistance is slightly poor. It is used for high mechanical properties and corrosion resistance. On some parts, it can only be applied after hot working.
SUS 410 is a representative type of martensitic stainless steel. Generally after the product is molded, it needs to be tempered to meet the strength requirements.
3 Brass is an alloy of copper and zinc, which is resistant to corrosion, heat transfer, and electrical conduction. It is generally used for screws with conductive requirements and low mechanical properties.
4 Copper is a kind of relatively pure copper, which can generally be considered as pure copper. Its conductivity and plasticity are better, but its strength and hardness are worse.
5 Aluminum has good thermal conductivity, conductivity, and ductility. In common metals, the conductivity is second only to silver and copper, but the density is only 1/3 of that of steel.
Because of its good ductility, aluminum is mainly used to produce various types of rivets