Fasteners come in a wide selection of specifications, but whether you are planning to usage a bolt, screw, rivet, peg, clamp, or some type of self-clinching hardware, picking material perfect for the intended application is vital concern. For example, selecting a fastener made of steel quite than aluminum have the right to greatly affect the quality and also duration of the joint it forms. Plenty of factors, together as ecological circumstances, presence of corrosive elements, physical stress requirements, and overall structure stability, can an in similar way influence material effectiveness.

You are watching: What metal are screws made of

Types that fasteners

Image credit: Shutterstock/APPOLLOMAN

The majority of industrialfasteners are created from aluminum, brass, specific synthetic non-metals, and also various grades of steel and stainless steel. In addition, metals such as titanium space also valuable for structure fasteners, return they have very certain applications in a narrow variety of fields. Generally, fastener products are judged on their mechanical properties, potential because that post-fabrication treatments, cost-efficiency, and several other an additional criteria. Friend can additionally get castle custom-made to suit her needs.

Steel Fasteners

Steel is the most typically used product in fastener production, constituting almost 90 percent of all fasteners manufactured annually. This metal’s popular stems indigenous its high degree of formability coupled through tensile strength and also durability. Compared to other steel stock, stole is also fairly inexpensive come fabricate. The is commonly processed v zinc or chrome plating, however can additionally be developed without any kind of surface treatments.

Carbon stole Bolt Grades

Carbon stole is the many common form of steel supplied in fastener production. Grades 2, 5, and also 8 are frequently the traditional for carbon-steel based screws and also bolts, with alloyed carbon steel being a higher-end variation on this metals. Their mechanical strength varieties from about 50 ksi (kilo-pound every square inch) approximately 300 ksi in a perfect product. Material properties because that these qualities include:

Grade 2: This is a short carbon group that attributes the the very least expensive, but likewise least durable, varieties of steel. Grade 2 product is highly workable, and forms the mass of steel grade fasteners.Grade 5: great 5 steels are created from unalloyed tool carbon groups, together as type 1038, and also are typically work-hardened to enhance their strength. This is the most usual grade used in automotive applications.Grade 8: these steels are typically medium carbon alloys, together as types 4037 and also 4340. They are work-hardened come a high degree, making lock stronger and better-suited because that mechanically straining applications, like car suspension systems.Alloy Steel: This is one alloy formed with high-strength carbon steel that deserve to be thermally treated up to 300 ksi. Alloy steel has low corrosion resistance and also typically benefits from extr coating. This steels are exceptionally strong, but can be rigid and brittle.

Stainless steel Fasteners

Stainless steel is one alloy the combines the nature of low carbon qualities with specific percentages of chromium and nickel. That is chromium component lends stainless steel a high degree of corrosion resistance the does not decrease from deformation or long-term use. However, the short carbon content avoids it indigenous being efficiently hardened, do the steel stronger than most grade 2 steels, however weaker than many hardened great 5 and 8 varieties. The final strength of many stainless steel qualities ranges from approximately 70 to 220 ksi, relying on the proportion of metals in the alloy. Stainless stole fasteners are also less magnetic than their standard steel counterparts. The two key categories ofstainless stole fastenermaterials are:

Martensitic Stainless Steel: The martensitic group consists of strong, durable stainless steels that can be more strengthened through warm treatments. Lock are an ext magnetic than other varieties of steel, but have lower corrosion resistance.Austenitic Stainless Steel: The vast bulk of stainless stole fasteners are produced with steels from the austenitic family. Their high level of chromium and also nickel administer tough corrosion resistance and also the ability to withstand significant physical strain without fracturing, albeit in ~ a greater cost than the martensitic varieties.

Bronze and Brass Fasteners

The bronze offered in fastener manufacturing is one alloy mostly consisting that tin and also copper. With its high corrosion resistance, bronze is well-suited for aquatic applications, such as shipbuilding or underwater construction.

It share copper’s reddish color, yet is fairly expensive contrasted to other fastener materials. Brass, one alloy the copper and also zinc, is similar to copper in the anti-corrosive and also electric conductivity properties, however it has lower tensile strength and also is a fairly soft metal. Part of brass’s appeal as a fabricating material lies in that is yellowish gold color.

See more: Why Do Guinea Pigs Lick You ? Why Does My Guinea Pig Lick Me

Nylon Fasteners

Nylon is a lightweight man-made plastic material used for specific fastener applications. That is corrosion-resistant, has actually high electrical and also thermal insulating properties, and can be conveniently dyed to satisfy aesthetic requirements, such together those essential for fastener replacement. However, nylon is topic to severe degradation under elevated temperatures and may become weakened in low-temperature conditions. In addition, its comparatively short tensile strength makes it less reliable for applications v demanding physical anxiety requirements.