Stainless steel is a high alloy steel that can resist corrosion in air or chemically corrosive media. Stainless steel does not need to undergo surface treatment such as color plating, but it can also have the inherent surface properties of stainless steel. From a metallographic perspective, stainless steel contains chromium, which forms a very thin chromium film on the surface. This film can isolate the stainless steel castings from intruding oxygen, thus providing corrosion resistance. In order to maintain the inherent corrosion resistance of stainless steel, generally speaking, stainless steel must contain more than 12% chromium.
347 stainless steel is a grade in the ASTM A240/240M standard. It is an austenitic stainless steel. In China, the corresponding grade of 347 stainless steel is 0Cr18Ni11Nb. Because it contains a certain amount of niobium (Nb) element, 347 stainless steel has good resistance to crystallographic corrosion, and has relatively high strength and plasticity. 347 stainless steel has good oxidation resistance and weldability in air below 800°C.
347 stainless steel has good corrosion resistance in chemical media such as acids, alkalis, and salt solutions. The high-temperature stress rupture performance and high-temperature creep resistance stress mechanical properties of 347 stainless steel are better than those of 304 stainless steel. Its application fields are also very wide, such as aviation, power generation, chemistry, petrochemical industry, food, paper making, exhaust manifold, etc.
The chemical composition of 347 stainless steel is as follows:
Carbon C: ≤0.08%
Silicon Si: ≤1.00%
Manganese Mn: ≤2.00%
Phosphorus P: ≤0.045%
Sulfur S: ≤0.030%
Chromium Cr: 17.00~19.00
Nickel Ni: 9.00~12.00
Niobium Nb: ≥10*C %
The mechanical properties of 347 stainless steel (solid solution state) are as follows:
Yield strength (N/mm2) ≥205
Tensile strength (N/mm2) ≥515
Elongation (%) ≥ 40
Hardness: HB: ≤187
Post time: Dec-09-2023