AISI 303 – X8CrNiS18-9 – DIN 1.4305

303 grade is considered to be the most optimal and efficient choice for machinability within the austenitic group of stainless steel alloys, but only when utilizing the appropriate tools, techniques, and processes to achieve the desired results.

The high sulphur content of 303 grade stainless steel is responsible for its superior machinability when compared to other austenitic grades.

Sulphur has long been known to enhance machinability in metals due to its ability to form sulphide inclusions that break up the chip during machining, resulting in a smoother surface finish and improved productivity. However, this benefit comes at a cost. The presence of sulphur also reduces the corrosion resistance, formability, and weldability of the alloy.

The formation of sulphides can lead to localized corrosion and pitting, which can compromise the integrity of the material in aggressive environments. Additionally, sulphur reduces the formability of the alloy, making it unsuitable for applications that require deep drawing or bending.

Welding 303 grade stainless steel is also a challenge due to the presence of sulphur, which can lead to hot cracking and reduced weld strength. Thus, while the high sulphur content of 303 grade makes it an ideal choice for machining, it may not be the best option for applications that require high corrosion resistance, formability, or weldability.

303 grade is not suitable for deep drawing or bending. Welding is possible with the right tools, but not recommended for 303 grade.

Heat resistance is similar to 304 grade, therefore can be used up to 700°C.

Sole purpose of this grade is free machining, and for other applications other grades show better results.

Alternative grades: AISI 304

Available forms: Round Bars, Flat Bars, Hexagon Bars, Square Bars

Available forms in our stocks: Round Bars, Hexagon Bars, Square Bars

Given data is based on theoritical vaules and intended as informative purposes only. Given data may be revised at any time without prior notice. Stainless steels may vary in performance under different circumstances. Hisco Steel will not be held responsible for any consequences derived from the end use or the application of the materials.

Here is the photo of 303 grade round bar