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1 carbon steel |
Currently, the most commonly used material in the fastener industry is carbon steel because of its high plasticity and lower cost compared to other materials. |
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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. |
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Ultra-low carbon steel, special material for tail hole pot nails. |
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Low carbon mild steel, used for general screws that do not require heat treatment (hardening), with a strength of 3.6 grade |
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Mild steel, used for general screws that do not require heat treatment (hardening), with a strength of 4.8 level |
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Medium carbon steel, used for general screws without special mechanical performance requirements, with a strength of 8.8 level |
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High carbon steel is generally not used for fastener production. |
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2 stainless steel |
Stainless steel is usually divided into austenitic steel, martensitic steel, and ferritic steel according to the state of organization. |
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Austenite (18%Cr, 8%Ni) contains more than 18% chromium, and also contains about 8% nickel and a small amount of molybdenum, titanium, nitrogen and other elements. The comprehensive performance is good, and it can withstand a variety of media corrosion. This kind of steel has good plasticity, toughness, weldability and corrosion resistance. |
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Because of the high chromium content, ferritic stainless steel has good corrosion resistance and oxidation resistance, but its mechanical properties and process properties are poor. It will cause brittleness when it exceeds 400℃, so it is mostly used for household appliances and decorations. . |
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Martensite (13%Cr) has higher strength, hardness and wear resistance due to its higher carbon content, but its corrosion resistance is slightly worse. It is used for higher mechanical properties and general corrosion resistance. For some of the parts, it can only be applied after thermal processing. |
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SUS 410 is the representative steel grade of martensitic stainless steel. Generally, after the product is formed, it needs to be quenched and tempered to meet the strength requirements. |
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3 Brass |
is an alloy composed of copper and zinc, which has the functions of corrosion resistance, heat transfer and electrical conductivity. Generally used for screws with electrical conductivity requirements and low mechanical performance requirements. |
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4 Copper |
is a relatively pure type of copper, which can generally be approximated as pure copper. It has good electrical conductivity and plasticity, but its strength and hardness are worse. |
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5 Aluminum |
has good thermal conductivity, electrical conductivity, and ductility. Among common metals, conductivity is second only to silver and copper, but the density is only 1/3 of steel. |
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Because of its good ductility, aluminum is mainly used in the production of various rivets. |
