Wear of shot blasting blades is a complex process influenced by multiple factors, which can be summarized into the following five key factors:

1. Material and Manufacturing Process

The material of the blade is its inherent characteristic determining its wear resistance, while a sophisticated manufacturing process is the foundation for its performance.

Material Selection: High-chromium cast iron (chromium content >18%) is the mainstream material in the market, offering high cost-effectiveness; tungsten carbide composite materials have 3-5 times the wear resistance of high-chromium cast iron and are suitable for high-wear conditions; special alloys or ceramics are used in extreme environments, but are expensive.

Manufacturing Defects: Casting defects such as sand holes and porosity inside the blade can become stress concentration points, easily leading to fracture under high-speed impact.

Heat Treatment Process: Ideal heat treatment should achieve a surface hardness of HRC60-65 while maintaining internal toughness to prevent brittle fracture. Poorly manufactured blades will exhibit coarse grains or obvious defects on the fracture surface. 2. Characteristics of Abrasive (Shot Grenade)

Abrasive is the direct "enemy" impacting the blades, and its properties have a decisive influence on the wear rate.

Hardness and Shape: Using harder abrasives (such as cast steel shot vs. cast iron shot) or angular steel grit will produce a stronger cutting action than spherical steel shot, accelerating wear.

Particle Size Uniformity and Cleanliness: Uneven abrasive particle size will lead to poor dynamic balance of the shot blaster, exacerbating blade vibration and irregular wear. Excessive broken particles and dust in the abrasive will create a "grind paste" effect, drastically accelerating blade wear.

Therefore, regularly cleaning the dust removal and separation system to ensure abrasive purity is one of the most economical and effective means of extending blade life.

3. Equipment Operating Conditions and Maintenance Status

Even with high-quality blades, poor equipment conditions will lead to premature failure.

Replacement and Dynamic Balancing: Blades must be replaced in sets (usually 8 blades per set), and the weight difference between individual blades must not exceed 5 grams. Otherwise, the impeller's dynamic balance will be disrupted, causing severe vibration and leading to abnormal blade wear or breakage.

Thrust Speed: Excessively high thrust speeds exponentially increase the impact energy of the abrasive. While improving cleaning efficiency, this drastically accelerates blade wear. A reasonable speed should be selected while meeting process requirements.

Wear of Other Components: Wear of components such as the directional sleeve and shot distribution wheel makes it impossible to accurately control the shot trajectory, causing the shot to impact the inner wall of the equipment or non-working areas, indirectly increasing the burden on the blades.

4. Characteristics of the Workpiece Processed: The "hardness" of the workpiece directly determines the working intensity of the blades.

Workpiece Material Hardness: Cleaning high-hardness castings (such as high-manganese steel) causes much faster blade wear than cleaning ordinary steel structures. 5. Workpiece Shape and Oxide Scale: Oxide scale, rust, or burrs on the workpiece surface increase the abrasive breakage rate, forming more abrasive particles and intensifying the erosion of the blades.

6. Synergistic Effect of Wear and Fatigue: Blade failure is not caused by a single factor, but rather by the combined effects of wear and fatigue.

Wear: Repeated impacts from the projectiles cause plastic deformation and carbide spalling of the blade surface metal, forming grooves and holes.

Fatigue: Blades are subjected to cyclic stress during high-speed rotation. Stress concentration points (such as the edges of casting defects and geometric transition zones) will first develop microcracks, eventually leading to static load fracture.

Therefore, stress concentration is the root cause of blade failure, and any design or maintenance measures that reduce stress concentration can effectively extend blade life.