A4 stainless steel – The Inox stainless steel with good acid and corrosion resistance properties
Many alternative names exist for A4 stainless steel. For example, names such as AISI 316 or V4A can also be found for A4. After all, however, despite its different names, it is always the same stainless steel: a non-corrosive high-grade steel with good acid and corrosion resistance properties. The austenitic steel, hence the “A” in front of the 4, is steel with more than 8% nickel content. The chromium contained makes it a stainless steel, also known as non-corrosive high-grade steel. Besides martensitic and ferritic steels, it also belongs to the group of stainless high-grade steels. The molybdenum alloy in the steel significantly improves its corrosion and acid resistance. This is where it differs from A2 stainless steel. The combination of its good mechanical properties and high corrosion stability makes it a very commonly used material, particularly in connection technology. It is not a coincidence that the stainless steel screw made of AISI 316
can be found in many places.
A4 is classified in Corrosion Resistance Class (CRC) III.
A4 (V4A) stainless steel
and its main properties
Compared with the properties of A2 steel, the alloying with molybdenum makes A4 significantly more resistant to corrosion and acids.
It can be used in temperatures of up to -60 degrees Celsius and demonstrates good weldability. A4 stainless steel screws also provide relatively good resistance to seawater and acidity compared to A2.
Possible uses of A4 stainless steel
Typical applications for screws and connecting elements made of A4 stainless steel are environments in close proximity to salt water.
A2 stainless steel screws are unsuitable owing to the high salt content of the water and air in these environments. A4 stainless steel is also used in the chemical and food industry because of its good acid resistance. V4A stainless steel is widely used in the pulp industry, because as an acid-resistant steel, it has been developed amongst other things for sulphuric acids in a boiling state. A4-alloyed fixtures are also replacing hot-dip galvanised fixtures on European motorways more and more. For example, many noise protection barriers and guardrail systems are now anchored to bridges using threaded rods/threaded elements made of A4 stainless steel. The bracketing systems of bridge drainage pipelines are also attached using A4. Further fields of application include the renovation of chimneys and certain areas of indoor swimming pools. However, stainless steel grades with a higher molybdenum content, such as special material 1.4529, still need to be used for safety-relevant components in indoor swimming pools that cannot be regularly cleaned or are constantly wetted with water.
- Chemical industry
- Food industry
- Pulp industry
- Chimney renovation
- Certain areas in indoor swimming pools
and many more
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have any questions about the properties or applications for this
type of stainless steel. We will be
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detail on this topic and find suitable products for you.
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