Introduction to Blast Media
This document discusses the use of various blast media for cleaning, paint removal, and etching. It highlights the limitations and health risks associated with traditional sand blasting, particularly the risk of silicosis from silica sand. It also warns against using cheap imported glass bead media due to potential contamination with heavy metals.

Factors Influencing Blast Media Selection
The selection of blast media depends on several factors including mass, shape, size, density, hardness, chemical composition, speed and direction of impact, and the substrate being blasted. The document emphasizes the importance of choosing the right media based on these properties to ensure effective and economical blasting.

Types of Blast Media
1. Aluminium Oxide/Silicon Carbide: Used for cleaning, etching, and surface preparation.
2. Glass: Primarily in bead form for cleaning and peening metallic components.
3. Metals: Steel, iron, aluminium, and brass for cleaning and peening.
4. Plastics: Used for cleaning, deburring, and paint stripping.
5. Ceramics: For finishing and peening with long bead life.
6. Natural Products: Corncob and granulated shells for sensitive cleaning.

Properties of Blast Media
1. Density: Heavier particles deliver more energy but can be compensated by velocity.
2. Shape: Spherical particles create a peened finish, while angular grit generates an etched finish.
3. Size: Smaller particles reduce process time, while larger ones create more texture.
4. Hardness: Determines the aggressiveness and potential for surface modification.
5. Breakdown: Fracture resistance affects cost and quality of surface preparation.

Guidelines for Selecting Blast Media
1. Choose the least aggressive media to minimize wear and maintenance.
2. Use the smallest particle size for efficiency.
3. Opt for the lowest blast pressure to save energy and reduce costs.

Guyson's Services
Guyson offers evaluation services to determine the best combination of blast media and equipment for specific applications. They encourage prospective users to submit sample components for feasibility testing to ensure optimal results.