Heat-Strengthened Glass

Heat-strengthened glass is a specially heat-treated product whose performance lies between that of ordinary annealed glass and fully tempered glass. Through a quenching process that is more gentle than full tempering, it develops a moderate surface compressive stress (typically 24-52 MPa), achieving a unique balance between strength, flatness, and workability.

Key Characteristics

• Enhanced Strength: Bending strength is approximately 2-3 times that of ordinary annealed glass, but lower than fully tempered glass (3-5 times).

• Excellent Flatness: Surface optical distortion (quench marks) is significantly less than that of fully tempered glass, resulting in high visual quality.

• Specific Breakage Pattern: When broken, it forms large, radial cracks and is NOT classified as safety glass.

• Post-Treatment Workability: Can still be cut or drilled after heat treatment (requires caution).

Core Applications
Primarily used in applications requiring both high flatness and strength, where the use of safety glass is not mandated by codes, such as:

1. Curtain walls of high-rise buildings (to meet wind load requirements and minimize image distortion).

2. Large viewing windows and skylights.

3. Glass components requiring precise mechanical processing after heat treatment.

Important Warnings

• It is strictly prohibited for use in locations where safety glass is required by regulations (e.g., railings, overhead glazing, impact-prone areas).

• Must be clearly marked (e.g., "HS") to prevent confusion with fully tempered glass.

In summary, heat-strengthened glass is a precision-engineered material designed for specific project needs. Its value lies in balancing high strength with high flatness. The key to its correct application is a thorough understanding of its performance limits and safety regulations.