JIS G4304 / G4312 SUH 309 Stainless Steel Composition & Heat‑Resistant Properties for High‑Temperature Components
SUH 309 is a heat‑resistant stainless steel defined in JIS G4304 / G4312 for high‑temperature structural applications. As a specialized heat‑resistant stainless steel, it contains 22–24% chromium and 12–15% nickel, with optimized carbon and trace elements to improve creep strength compared with standard SUS 309.
SUH 309 performs reliably at 950–1050°C and is used in combustion chambers, furnace components, heat‑treatment fixtures, exhaust systems, and high‑temperature transfer structures. It offers strong oxidation resistance and excellent thermal‑fatigue stability. SUH 309 is supplied as plates, tubes, bars, and forgings. It is widely used in high‑temperature equipment manufacturing and thermal‑processing industries.
SUH 309 performs reliably at 950–1050°C and is used in combustion chambers, furnace components, heat‑treatment fixtures, exhaust systems, and high‑temperature transfer structures. It offers strong oxidation resistance and excellent thermal‑fatigue stability. SUH 309 is supplied as plates, tubes, bars, and forgings. It is widely used in high‑temperature equipment manufacturing and thermal‑processing industries.