Heat Treatment Chemicals Used as Catalysts or Add...

Heat Treatment Chemicals Used as Catalysts or Additives
1. Ammonium Chloride (Naushadar)
Role: Flux in galvanizing and annealing

Function: Removes oxide scale from metal surfaces during heat treatment

Common Use: Pickling steel before hot-dip galvanizing

2. Sodium Nitrate (NaNO₃) & Potassium Nitrate (KNO₃)
Role: Oxidizing salts in salt baths for nitriding and carburizing

Function: Provide nitrogen/oxygen to harden steel surface layers

Common Use: Salt bath nitriding to increase surface hardness

3. Sodium Carbonate (Na₂CO₃) (Soda Ash)
Role: Flux and cleaning agent in heat treatment

Function: Helps remove impurities and scales; used in carburizing powders

4. Boric Acid (H₃BO₃)
Role: Protective coating in brazing and annealing

Function: Prevents oxidation during heating by forming a glassy protective layer

5. Sodium Silicate
Role: Binder in heat treatment powders/coatings

Function: Holds carburizing compounds on the metal surface during heat treatment

6. Potassium Fluoride (KF)
Role: Catalyst in surface treatment and brazing fluxes

Function: Helps remove oxides from surfaces, improves wetting

7. Zinc Chloride (ZnCl₂)
Role: Flux in annealing and galvanizing

Function: Removes oxide layers and promotes clean metal surfaces

8. Sodium Thiosulfate (Na₂S₂O₃)
Role: Used in quenching baths and pickling

Function: Acts as an oxygen scavenger, preventing scale formation

9. Ammonium Sulfate ((NH₄)₂SO₄)
Role: Used in some carburizing and nitriding powders

Function: Supplies sulfur and nitrogen to modify surface properties