Aluminum die-casting surface treatment What are the ways?

- Jan 09, 2018 -

1. manual processing:

   Such as scraper, wire brush or grinding wheel. By hand to remove the surface of the workpiece rust and scale, but the manual handling of labor-intensive, low productivity, poor quality, cleaning is not complete.

2. Chemical treatment:

   The main use of acid-base or alkaline solution and the workpiece surface oxide and oil chemical reaction to dissolve in acidic or alkaline solution, in order to achieve the removal of the surface of the workpiece rust scale and oil, then the use of nylon Into a brush roller or 304 # stainless steel wire (acid-base solution made of wire brush roll clean can achieve the purpose of chemical treatment adapted to the sheet metal parts clean-up, but the disadvantage is that if the time is not properly controlled, even if the corrosion inhibition Agents, but also can cause steel over-eclipse phenomenon, for more complex structural parts and porous parts, the acidic solution pickling, immersion gap or hole in the residual acid is difficult to completely remove, if not properly handled, will become the workpiece after Corrosion and hidden dangers of chemicals, and volatile chemicals, high cost, chemical emissions after the treatment of work is difficult, if not properly handled, will cause serious pollution to the environment .As people's awareness of environmental protection, this treatment is being mechanical treatment Act to replace.

3. mechanical processing method:

   Including wire brush wire drawing method, mechanical polishing method, shot peening method.

   (1) wire brush roller polishing method is the brush roller driven by the motor, the brush roller and the rolling movement in the opposite direction at the upper and lower surface of the strip rotating high-speed brush to the oxide. Brush off the oxide scale closed circulating cooling water washing system washed away.

   (2) Mechanical polishing is based on cutting, plastic deformation of the material surface to remove the convex portion after polishing to obtain a smooth surface polishing method, the general use of whetstone, wool wheel, sandpaper, etc., mainly to manual operation, special parts such as slewing Surface, you can use aids such as turntables, high surface quality requirements can be super-precision polishing method. Ultra-precision polishing is the use of special abrasive, grinding fluid containing abrasive polishing press on the workpiece surface, for high-speed rotary motion. The surface roughness of Ra0.008μm can be achieved by this technique.

   (3) Shot peening is divided into shot blasting and sandblasting:

    Steel balls or sand for surface treatment, striking power, clear effect. However, the shot blasting on the sheet metal workpiece easily deforms the workpiece, and the shot hit the surface of the workpiece (either shot blasting or shot peening) to deform the metal base material. Since Fe304 and FE203 have no plasticity, With the deformation of wood, so with the oil of the workpiece, shot blasting, sand blasting can not completely remove oil. In the existing surface treatment methods, the best cleaning effect of the number of blast cleaning. Sandblasting is suitable for the surface cleaning of the workpiece. Blasting process can produce large amounts of silica dust can not be cleared, seriously affecting the health of workers and pollute the environment.