Free Machining AISI 303 Stainless Steel Bars Round Square Hexagonal Shape

303 is the most common “free-machining” grade using sulphur to produce sulphides allowing easier
chip-breaking during machining. Basically it is 304 with sulphur.

Stainless 303 grade combines the following characteristics:

• Fair pitting corrosion resistance but significantly lower than 304.
• Improved machinability compared to 304. Machinability index 60% improvement compared to 304
• Poor weldability
• Higher leaching rates of Cr and Ni than normal austenitic stainless steels

303 is a basic stainless steel where high productivity is required. Normally, austenitic stainless steels like 304
are difficult to machine. The high work hardening rate of austenitic stainless steels produces greater tool wear
and a tendency to produce “stringy” chips during machining.
The situation is made worse by the lower thermal conductivity and higher thermal expansion of these steels.

303 uses sulphur (0.15/0.35%) to produce a large number of manganese sulphide inclusions.
These inclusions allow increased speeds and reduced tool wear.
The disadvantages of sulphide inclusions are reduced corrosion resistance, poor weldability and
greater propensity to leach chromium and nickel ions in contact with aqueous fluids.
The last item means that 303 is not authorised to be used in contact with drinking water nor for jewellery.
Nevertheless, 303 is used in many applications where basic corrosion resistance is required.

Applications which illustrate these features include:
Threaded fasteners, shafts, valve bodies, precision measurement devices, pneumatic manifolds.

Delivery forms

Our 303 stainless bar products program include round, square, hexagon, and flat.

all in the drawn, hot rolled, peeled, and centerless ground.

For Details, please Contact

WUXI GUANGLU Special Steel Co., Ltd.

Stainless martensitic • precipitation hardening steel • stainless ferritic — Our answer to your needs

Tel: +86 510 81812873

Email: export@guanglusteel.com