What Material Is 253MA Stainless Steel ?

253MA/UNSS30815 is a kind of heat resistant stainless steel developed on the basis of 21cr-11ni stainless steel by alloying rare earth elements CE and CN. Generally, 253MA is austenite. Due to the interaction of rare earth elements and silicon, the material still has good oxidation resistance at 1150 ℃. However, the existence of cyanide, carbon, rare earth elements and alkali metal oxides makes 253MA have the same stress rupture strength as Ni based alloy. Therefore, 253MA can replace the expensive nickel base alloy, and can be widely used in high temperature parts with working temperature above 900 ℃ and pressure bearing occasions below 900 ℃.

Executive standard: ASTM A240/ASME SA-240, ASTM A276, ASTM A182/ASME SA-182, ASTM A312/ASMES A312

Main components: carbon (C) 0.05～0.10, phosphorus (S) ≤20.03, nickel (Ni) 10.0～12.0, silicon (Si) 1.4～2.0, chromium (Cr) 20.0～22.0, nitrogen (N) 0.14～0.20, Cerium (Ce) 0.03～0.08

Mechanical properties: tensile strength: σb≥650Mpa, yield strength σb≥420Mpa: elongation: δ≥40%

Corrosion resistance and main use environment: 253MA is an alloy obtained by increasing the nitrogen content on the basis of alloy 1.4828 and adding rare earth elements for microalloying. It has good oxidation resistance, good high temperature corrosion resistance, and good The high temperature mechanical strength. The most suitable temperature range is 850-1100℃. If it is used in the range of 600 to 850℃, the impact toughness at room temperature will decrease due to structural changes.

The chemical composition of 253MA is balanced, so that the steel has the most suitable comprehensive performance in the temperature range of 850℃-1100℃, extremely high oxidation resistance, and the temperature of the scale is as high as 1150℃; extremely high creep resistance Ability and creep rupture strength; in most gaseous media, it has good resistance to high temperature corrosion and constant brush corrosion; high yield strength and tensile strength at high temperatures; good formability and weldability , And sufficient machinability.

In addition to the alloying elements chromium and nickel, 253MA stainless steel also contains a small amount of rare earth metals (Rare Earth Metals, REM), which significantly improves its oxidation resistance. Nitrogen is added to improve creep properties and make this steel completely austenitic. Although the content of chromium and nickel is relatively low, this stainless steel has the same high temperature characteristics as highly alloyed alloy steels and nickel-based alloys in many cases.

Application areas: 253MA is widely used in sintering equipment, blast furnace equipment, steel melting, melting furnace and continuous casting equipment, rolling mill (heating furnace), heat treatment furnace and accessories, mineral equipment and cement production equipment, etc.