What is the difference between stainless steel 304 and 321?

1. Different properties
1. 321 stainless steel: Ni-Cr-Ti type austenitic stainless steel. 321 stainless steel is Ni-Cr-Ti type austenitic stainless steel, and its performance is very similar to 304, but due to the addition of metal titanium, it has better resistance to intergranular corrosion and high temperature strength. Due to the addition of metal titanium, the formation of chromium carbide is effectively controlled.
2. 304 stainless steel: It is a common material in stainless steel, with a density of 7.93 g/cm3. Common marking methods on the market include 06Cr19Ni10 and SUS304.

2. Different characteristics
1. 321 stainless steel: It has abrasion resistance, high temperature resistance, creep resistance, etc. Ti in 321 stainless steel exists as a stabilizing element, but it is also a heat-resistant steel grade, which is much better than 316L at high temperatures. 321 stainless steel is in organic and inorganic acids of different concentrations and temperatures.
2. 304 stainless steel: The most important elements in 304 are Ni and Cr, but they are not limited to these two elements. Specific requirements are specified by product standards. The industry generally believes that as long as the Ni content is greater than 8% and the Cr content is greater than 18%, it can be considered 304 stainless steel.

3. Different uses
1. 321 stainless steel: used to manufacture linings and pipelines for wear-resistant acid containers and wear-resistant equipment. Applicable to outdoor machines in the chemical, coal, and petroleum industries with high requirements for resistance to intergranular corrosion, heat-resistant parts of building materials, and parts that are difficult to heat treat.
2. 304 stainless steel: widely used in industry, furniture decoration, food and medical industries.