What is the production process of Q355GNH sheet?

Q355GNH steel sheet is atmospheric corrosion resistant steel. It is a kind of low alloy steel that has better corrosion resistance in the atmosphere than ordinary carbon steel by adding a small amount of alloying elements. Among them, the q35gnh weather-resistant board has been widely used in containers, railway vehicles, bridges, buildings and air preheaters that require atmospheric corrosion resistance.

Production process flow:

Blast furnace molten iron → molten iron pre-desulfurization treatment → 120t converter → LF refining → continuous casting → slab heating → controlled rolling → controlled cooling → stack slow cooling → flaw detection → shearing → sampling inspection → marking → storage.

Q355GNH sheet chemical composition%:
C: 0.22-0.29, Si: 0.17-0.37, Mn: 0.50-0.80, Mo: 0.90-1.10, Cr: 2.10-2.50, V: 0.30-0.50, P: 0.035, S: 0.035, Cu: 0.30, Ni: 0.30
Mechanical properties of Q355GNH sheet:
 Yield point (σs/MPa): ≧785, elongation after fracture (δ5/%): ≧14, reduction of area (ψ/%): ≧55, impact absorption (Aku2/J): ≧63 

Q355GNH steel technical requirements:

Compared with welded weathering steel q355nh, Q355GNH weathering steel sheet has better atmospheric corrosion resistance. It is necessary to ensure that the steel plate has high strength, while having good plasticity and toughness. In addition, it generally reflects its good corrosion resistance by adding corrosion resistance elements to ensure the atmospheric corrosion resistance index.