A2 & A4 Stainless Steel Screws, Fasteners and Fixings
Stainless steels are available in a number of different grades that are often found within the fastener industry, used in screws, nuts, bolts and other fixings.
There’s a number of exceptional types of stainless steel with A2 and A4 being the most popular.
Types 301, 303, 309 and 312 all offer very distinct properties, including temperature resistance, affordability, corrosion resistance and ductility.
A2 Stainless Steel Fasteners
A2 stainless steel fixings are made from an alloy containing a mixture of two or more metals.
The steel within the fixing must contain at least 10.5% chromium to be considered or called stainless, and this chromium makes the metal more corrosion resistant and less likely to stain than other steels. The corrosion resistance is created by steel forming a layer of chromium oxide.
These fasteners often contain molybdenum, titanium, nickel or copper for enhanced or increased properties such as strength, corrosion resistance and formability.
A2 stainless steel fasteners can be found across a number of industries including hospitality and medical. Sometimes referred to as ‘Type 304 Stainless Steel’, it is made out of 18% chromium and 8% nickel.
A4 Stainless Steel Fasteners
There is no evident visual difference between A2 and A4 stainless fasteners steel as they are both polished using the same process – but there are characteristics that provide a difference.
A4 stainless steel contains carbon, silicon, manganese, phosphorous, sulphur, chromium, molybdenum, and nickel. These elements make fixings manufactured from A4 steel very resistant to corrosion and less reactive to other materials.
A4 stainless steel fasteners are typically known as marine grade stainless fasteners due to their resistance to salt water corrosion and can be found in a number of water-based applications. It is also resistant to salt spray.
A4 stainless fasteners are easier to fabricate, clean, finish and weld, and whilst they are generally more expensive than A2 fasteners, they can be more cost-effective over a longer period of time due to the lack of maintenance or replacement required when used outside.
A4-70 Stainless Steel Fasteners
Stainless steel grade A4-70 is often used in surgical instruments, due to its non-reactive qualities and corrosion resistance.
A4-70 is an austenitic, acid proof stainless grade, cold worked to provide a minimum tensile strength of 700 MPa.
Security fixings manufactured from A4-70 stainless are popular for securing medical equipment, and our range of 5-lobe pin TX security screws are a popular choice.
Other materials and finishes are available, click here for details.
If you require more information or would like to enquire further, please send us your requirements.
Kitting and Packaging Service
Ideal for the furniture trade, we specialise in the supply of heat seal, grip seal and zip seal bags of screws and fasteners for your application.
Specials and non standard fixings
Looking for fixings with an unusual head diameter or thread length?
Need fasteners with a non-standard finish?
Or do you have other special requirements? Custom fasteners are no problem for Fastenright!
Fastener Terminology Glossary
There are a number of confusing names and terms within the Fastener industry, so we have created a handy terminology glossary to help.
The Fastenright specialist team is available to discuss your requirements.
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We look forward to helping you.