8 Most Common and Useful Grades of Stainless Steel

stainless steel barStainless steel consists of several alloy iron that has a minimum of 10.5% chromium in their overall composition. Each stainless steel composition has its unique characteristics of melting point, tensile strength, corrosion and oxidation resistance. Stainless steel industrial production keeps increasing every year because of its durability, versatility, and affordability.

Stainless steel is available in over 100 different grades, all of which are distinguished by their crystalline structure. In the year 1930, the American Iron and Steel Institute created the first stainless steel grade system. This method was then integrated with one developed by the SAE, Society of Automotive Engineers to create a more consistent numbering system. Steel producers may now employ multiple numbering systems, which can make things more complicated.

To choose the best stainless steel grade, you must first understand your options. In this article, you will read about the most prevalent types and grades of stainless steel that will help you in understanding your options.

Stainless Steel Type

Although there are hundreds of different stainless steel alloys, they may all be categorised into three groups.


This type of stainless steel is most commonly used. Austenitic stainless steels contain a higher chromium percentage than other alloys of steel, making them more corrosion resistant. Austenitic stainless steel is also non-magnetic by nature, though it can become magnetic following cold working.


This type of stainless steel is the second most commonly used after austenitic stainless steel. It is magnetic, just as the name suggests. Cold working can be used to harden these alloys. Because of the lower nickel content, they are also less costly.


Stainless steel alloys in this group are the least prevalent. They have a lower corrosion resistance than austenitic or ferritic alloys of stainless steel, but they are harder than them. Alloys of martensitic stainless steel are frequently used in applications that need extreme impact resistance and tensile strength. These alloys can be widely used with polymer coating in applications where corrosion resistance is also required.

Most Common Stainless Steel Grades

Each stainless steel grade is made up of different chemical structures, and, as a result, all of them differ in their physical image.

The most common stainless steel series is 300. The most common stainless steel bar stock in the 300 series is 304 stainless steel bar stock and 316 stainless steel bar stock. 409 and 430 grades of stainless steel are two more common grades.

Stainless Steel 300-Series

stainless steel barThe 300 series of stainless steel are austenitic. The main alloying addition includes chromium around 18%-30%, while nickel is only 6%-20%. It’s made of solid iron with a face-centred cubic (FCC) crystalline structure.

The 300-series grades of stainless steel are particularly valuable in the automotive, aerospace and construction industries due to their composition. 300 series stainless bar stock can only be hardened through cold working processes because it can withstand high temperatures.


Grade 301 is malleable and attractive, with high tensile strength as well as corrosion-resistant properties. 301 stainless bar stock is utilised for aesthetic structural applications due to its strong malleability and resistance to abrasion.


Stainless steel 303 round bar has the most machinability among all the grades of austenitic stainless steel. It is machinable as the sulphur is present in the composition of the stainless steel 303 round bar. Sulphur enhances machining while reducing corrosion resistance and toughness slightly. Stainless steel 303 round bar has a lower corrosion resistance than 304. stainless steel 303 round bar is available from advance grinding.


This grade accounts for half of all steel produced on the planet. Grade 304 has an 18% chromium plus 8% nickel content, making it both aesthetically beautiful and durable. Because of its saline vulnerability, grade 304 could crevice or pit when exposed to saltwater. It is also available in 304 stainless steel round rods and 304 stainless steel bar stock.


It is the 2nd most widely manufactured steel, including 2%-3% of molybdenum. As a result, it’s more saline-resistant and hence more suited to coastal areas. 316 grade of stainless steel is also used to make a lot of surgical supplies. 316 stainless steel round rod or 316 stainless bar stock is in stock at advance grinding.


At high temperatures, this grade has great tensile strength. It’s more pitting and corrosion-resistant than stainless bar stock in grades 304 and 316. Grade 317 is more costly than other grades of 300-level because of its composition.

Stainless Steel 400-Series

The 400-series stainless steel is slightly magnetic because it includes 11% more chromium plus 1% additional manganese as compared to grades in the 300-series. The carbon percentage in this steel round rod is also higher. Therefore, 400-series stainless steel bar stock has more strength and wear resistance than grades of 300-series, but it also corrodes quickly. The 400-series stainless steel is hardened by heat treatment.


It’s free-machining martensitic chromium steel that’s widely regarded as the very first free-machining grade of stainless steel. It possesses the greatest machinability as compared to any other stainless steel. In the tempered and hardened state, it has good oxidation and corrosion resistance as well as high strength. grade 416 is easy to machine, magnetic at all times, and has minimal frictional characteristics that help prevent seizing and galling.


Grade 430 is ferritic steel that forms easily however does not hold up well to high temperatures and corrosion. It’s frequently utilised in decorative applications, like automotive trim. 430 stainless bar stock is also often used during backyard BBQ grills. As it doesn’t include nickel, it is cheaper than 304. 430 stainless steel round rods and sheets are usually stocked.


It’s ferritic stainless steel that resists sulfidation, oxidation and any other hot corrosion types well. Although its increased temperature strength remains relatively low, it is usually employed between 1500 to 2100°F.

Advance Grinding- Best Stainless Steel Grade Provider

Advance Grinding supplies stainless steel grades of various types, including the most common grades from the 300 and 400 series. Our products are subjected to stringent quality control procedures. We work hard to provide each customer with reassurance and excellent service. We can deliver the perfect grade of stainless steel alloy for your particular project, regardless of your order size or industry. Check over our product list online and contact us for a quote right away.

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