Sandblasting and shot peening
Sandblasting and shot peening
Sandblasting working principle
Sandblasting uses high-speed jets of abrasive particles to impact the surface of a workpiece, removing dirt, scale, burrs, or creating surface roughness through mechanical impact.
Sandblasting Media
- Al₂O₃
- White fused alumina
- Glass beads
- Steel shot
- Walnut shells，Plastic beads
Main Functions
1.Cleans surface oil, rust, and oxide scale.
2.Deburrs.
3.Roughens the surface, providing adhesion for coatings and plating.
4.Achieves surface polishing or decorative effects.
Features
1.Controllable impact force, adjustable from light to heavy.
2.Does not alter the mechanical properties of the workpiece.
3.Applicable to metals, plastics, glass, etc.
4.Surface roughness can be adjusted by particle size and pressure.
Shot peening working principle
Small particles (steel shot, steel grit) impact the surface of a workpiece at high speed, causing uniform residual compressive stress to be generated on the surface. Compressive stress can improve the fatigue strength and crack resistance of metals.
Shot peening media
- Steel shot
- Steel grit
Main functions
1.Enhances fatigue strength
2.Increases corrosion resistance and crack resistance
3.Improves stress concentration areas (gears, springs, bearings)
4.Can remove oxide scale or perform minor deburring, but the primary purpose is strengthening rather than cleaning.
Features
1.High impact force, can form a compressive stress layer, significantly improving fatigue life and strength, and surface properties can be controlled.
2.Minimal impact on workpiece dimensions, but impact strength and coverage must be controlled.
3.Commonly used for metal parts, especially bearings, springs, gears, and aerospace components.
Summary
Sandblasting uses irregular abrasive particles to impact the workpiece surface at high speed, achieving the effects of rust removal, dirt removal, oxide scale removal, and surface roughening. It can significantly improve the adhesion of coatings such as paint and electroplating. Although sandblasting can improve surface mechanical properties, its essence is cleaning and roughening. Prolonged sandblasting can lead to surface roughness, thereby reducing corrosion resistance.
Shot peening relies on the powerful impact force of the shot to generate residual compressive stress on the metal surface, thereby strengthening the surface, improving fatigue life, enhancing crack resistance, and improving wear resistance and corrosion resistance. Shot peening is a non-destructive strengthening technology and does not remove material. Compared to sandblasting, shot peening focuses more on strengthening than cleaning.