How to choose the right stainless steel grades?

Stainless steel is the most popular metal used in kitchenware and other commercial applications because of its durability and resistance to corrosion. However, stainless steels are vulnerable to corrosion if exposed to saltwater and certain chemicals. When purchasing the right stainless steel grades, you should make sure that the following four terms – Corrosion-resistant, mechanical properties, machinability, weldability, surface treatments, that’s depends on the degree of resistance to wear and corrosive solutions encountered during the finishing or seasoning process. Moreover, the type of finishing used and the degree of alloying in the construction determine the composition of the final grade.



Corrosion resistance includes non-rust and acid, alkali, salt and other corrosive media performance, as well as high-temperature oxidation resistance, corrosion resistance and other properties. Selecting the stainless steel project is to solve various corrosion problems encountered in engineering, and so the corrosion resistance of stainless steel in a corrosion environment can guarantee the equipment within the service life have enough ability to resist corrosion, to ensure the safe operation of the equipment, is a priority when select material should be paid attention to the following terms: the standard of corrosion resistance is determined by people, can not be limited by it and you can not ignore it, should use the conditions of use requirements to determine the appropriate grade.

So far, there is no stainless steel that has good rust resistance in any environment , corrosion resistance, but a grade is more suitable for a specific environment. It is worth noting that the choice of stainless steel should not only consider its general corrosion resistance but also consider its local corrosion resistance. Especially in water medium and chemical medium, the latter is particularly important. The use of experience has proved that the sudden destruction of stainless steel equipment and components, local corrosion is more harmful than general corrosion. When quoting the corrosion resistance data of stainless steel in various manuals and literature, attention should be paid to the fact that many of them are test data, and there are often large differences with the actual media environment.


Mechanical properties

Mechanical properties include strength, hardness, plasticity, toughness, fatigue and other properties. Note that most of these properties have been measured in atmospheric environments without strong corrosive media. When in corrosive media, these mechanical properties, such as fatigue strength, are significantly reduced and sometimes break far below their strength limits under static tensile stress and media. For the equipment under frequent load, in addition to the design of strength, also required to do fatigue design, for working at low temperature, and bear impact load of stainless steel components, must consider its low-temperature toughness, brittleness, transition temperature, low-temperature fracture toughness; Sometimes the coefficient of linear expansion must be considered.


Machinability, weldability, surface treatment

They are so-called technology, is the ability of stainless steel to adapt to the equipment manufacturing process, such as: after processing shape, size, precision, smoothness, etc.; Welding method.

In order to determine the good resistance against acids and oxidation, it is important to note the composition of the stainless steel. A good combination of this alloy with low carbon material will result into a combination of excellent corrosion resistance and excellent ability to resist impurities. The resulting combination has been aptly referred to as 904L, which stands for high alloy austenitic. With this alloy, you are guaranteed not only a sturdy machine but also the ability to cut through any kind of surface.

Grade 904L stainless steels are a low-carbon, austenitic stainless metal with high chromium content. This high chromium content improves its resistance to acids, including sulphuric acid, reducing the risk of corrosion. In addition, it enhances the strength of the structure by increasing its toughness and preventing fatigue cracking. We are a professional supplier and processing center of high-quality 904L stainless steel sheet and pipe, any interested in us, just give us a call.