In aluminum processing, nitrogen enhances surface quality through these key methods:
Inert Protection & Oxidation Inhibition
Nitrogen creates an inert environment during extrusion, effectively reducing surface oxidation that causes defects. This mirrors nitrogen-based atmosphere protection in metal heat treatment, significantly improving surface finish.
Heat Control & Efficiency Boost
Gaseous nitrogen rapidly dissipates heat generated during extrusion, lowering mold temperature to extend lifespan while stabilizing processing temperatures for dimensional accuracy.
Porosity Reduction
In aluminum alloy casting, nitrogen removes dissolved gases (e.g., hydrogen, CO₂), minimizing porosity and enhancing surface compactness. This technique is widely adopted in non-ferrous metal processing.
Process Safety Enhancement
As a purging gas in slagging or vacuum heat treatment, nitrogen prevents furnace explosions, ensuring stable processing conditions.