Insight // Laser Oxide Treatment for Powder Coating

When mild steel is cut using a laser cutter the exposed edge of the steel will develop an oxide layer.

The coating will adhere over the laser oxide layer but if physical pressure is exerted on the edge (impact) or if the edge is exposed to moisture and heat the oxide layer can break away from the steel and the powder coating will break away with the oxide layer. In order to protect the steel surface and prevent coating adhesion failure the laser oxide edge must be removed completely prior to application of the coating.

Treatment Options

  1. Mechanical Abrasion – blasting, grinding or sanding.
  2. Chemical – acid pickling with a strong acid solution; immersion is more effective than spray

The part should be cleaned and phosphated or coated very soon after the laser edge has been removed because the exposed steel can rust once the oxide layer has been removed. The addition of a cleaning and phosphating step will enhance adhesion and corrosion resistance after the laser oxide has been removed.