Medium chromium ferritic stainless steel 1Cr17 (AISI430), 1Cr17Ti (AISI437) Oxidation resistance

Chromium steels are widely used in stainless steel because of their outstanding oxidation resistance and corrosion performance. The chromium content in stainless steel ranges from 12 to 30 % and is usually referred to a series of chromiumiron-sulfur-nickel alloys. The series can be classified into five types: Cr12 (AISI410), Cr13 (AISI414), Cr17 (AISI430), Cr17 Ti (AISI 437) and Cr25 (AISI 316).

The 1Cr17 (AISI430) and 1Cr17 Ti (AISI 437) stainless steels possess good oxidation resistance at elevated temperatures. The 1Cr17 (AISI430) and 1Cr17Ti (AISI 437) stainless steels also have acceptable corrosion resistance in most environments. The corrosion resistance is similar to that of other chromium containing stainless steels, except that the 1Cr17 (AISI430) and 1Cr17 Ti (AISI437) stainless steels have a lower corrosion resistance in harsh and chloride containing environmental conditions.

The chromium content in both 1Cr17 (AISI430) and 1Cr17Ti(AISI437) stainless steels provides excellent oxidation resistance. When exposed to heat and oxygen, a dense and adherent oxide layer will form on the surface of the material and it will prevent further oxygen from reaching the metal and corroding it. This capability to resist oxidation and form a passive film of chromium rich oxides on its surface makes chromium stainless steels a much better choice for applications involving high temperature environments for extended periods of time.

The 1Cr17(AISI430) and 1Cr17Ti(AISI437) stainless steels’ mechanical properties largely depend on their alloying elements. Generally, these steels possess rather low strength and they are highly ductile and mostly non-magnetic. Although, they both possess an impressive elongation in the range of 20-30%, depending on the tempers.

These chromium containing stainless steels, 1Cr17 (AISI430) and 1Cr17 Ti (AISI437), are characterized by their excellent corrosion resistance and oxidation resistance. While 1Cr17 (AISI430) is more commonly used for applications which require good oxidation resistance and corrosion resistance in conventional environments, the 1Cr17Ti(AISI437) is especially resistant to pitting and crevice corrosion. Therefore, the 1Cr17Ti (AISI437) is the preferred choice for applications in hostile corrosive environments. Furthermore, due to their relatively low cost and good mechanical properties, both 1Cr17 (AISI430) and 1Cr17 Ti (AISI437) are widely used in many industrial applications.

Chromium Ferritic Stainless Steel 1Cr17 (AISI430) and 1Cr17Ti (AISI437)

Chromium ferritic stainless steel 1Cr17 (AISI430) and 1Cr17Ti (AISI437) are characterised by the addition of chromium to iron,which improves its oxidation resistance.

1Cr17 (AISI430) is a low cost steel with good mechanical properties and corrosion resistance, however, its corrosion resistance is still lower than that of austenitic and duplex stainless steel. Generally, its corrosion resistance is similar to 302/304 stainless steel in mild corrosion environments. In comparison with other ferritic stainless steel, it has good formability,weldability and polishing properties. 1Cr17 (AISI 430) are usually used in cookware and kitchen appliances, automobile trim and chimney vents, building facades, etc.

On the other hand, 1Cr17Ti (AISI 437) has improved corrosion resistance compared with 1Cr17 (AISI430) due to the addition of titanium. It is still prone to corrosion in acid liquids, but its corrosion resistance is improved in neutral and weakly alkaline solutions. It has higher strength than 1Cr17 (AISI430), and its formability,weldability and polishing properties are better than those of austenitic stainless steel. It is usually used in chemical and food industry, pump and valve industry and gas industry.

In conclusion,both 1Cr17 (AISI430) and 1Cr17Ti (AISI437) are chromium ferritic stainless steel with good corrosion resistance. Their corrosion resistance is lower than that of austenitic stainless steel. However, due to their low cost and good mechanical properties, they are widely used in many different industries.