ASME SA312 TP347H is approximately equivalent to China's 1Cr19Ni11Nb, which is a high-carbon austenitic stainless steel containing niobium Cr-Ni, because of the stabilizing element Nb, its intergranular corrosion resistance and resistance to polysulfate intergranular stress corrosion performance is good, in acid, alkali, salt and other corrosive media, its corrosion resistance line with Ti containing 18-8 austenitic stainless steel is similar, so it is widely used in boilers Power generation, petroleum, chemical, synthetic fiber, food, paper and other industries. Because Nb is less prone to burnout than Ti, this steel grade can be used as a weld core for welding chromium-nickel austenitic stainless steel. The steel has higher high-temperature strength and better resistance to high-temperature oxidation than the 316 series, so it is often used as a hot strength steel.
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