303 and 304 stainless steel are two commonly used stainless steel materials. They have some differences in chemical composition, mechanical properties and application range.

1.Differences in chemical composition

303 stainless steel is an easy-to-process stainless steel mainly composed of iron, chromium and nickel. It also contains small amounts of sulfur and phosphorus. The addition of sulfur makes 303 stainless steel has good processing properties, but it also reduces its corrosion resistance.

In comparison, 304 stainless steel is 18-8 stainless steel, containing 18% chromium and 8% nickel. 304 stainless steel has excellent corrosion resistance and high temperature oxidation resistance. 

2.Differences in mechanical properties

303 stainless steel has good processing properties due to its sulfur content. It is easy to cut and its shape can be changed through cold working and hot working. However, 303 stainless steel has lower strength and corrosion resistance.

In contrast, 304 stainless steel has high strength and corrosion resistance, suitable for for a wider range of applications.

3.Differences in application scope

Because 303 stainless steel has good processing properties, it is often used to manufacture fasteners, bearings and valves. In high-temperature environments, the sulfur content of 303 stainless steel can cause oxidation and desulfurization, so it is not suitable for some applications requiring high-temperature oxidation resistance.

In contrast, 304 stainless steel has good corrosion resistance and high temperature oxidation resistance under normal atmospheric conditions, so it is widely used in the manufacture of chemical equipment, food processing equipment, etc.

4.Price difference

Since 303 stainless steel has better processing performance and relatively low production costs, a certain price is generally cheaper.

304 stainless steel has high strength and corrosion resistance, so the price is relatively high.

Summarize:Because 303 stainless steel contains sulfur, it has good processing properties and is suitable for manufacturing fasteners, bearings, valves, etc.; while 304 stainless steel has high strength and corrosion resistance and is suitable for manufacturing chemical equipment, food processing equipment, etc. When selecting stainless steel materials, the selection needs to be based on specific application requirements to ensure the performance and reliability of the material.