FATIGUE
The Problem: Repeated Stress Leading to Failure of Materials
Fatigue failure of materials is a critical concern in industrial components subjected to cyclic mechanical or thermal stress. Even when stress levels remain below the ultimate strength of a material, repeated loading can lead to microcrack formation, propagation, and eventual catastrophic failure.
Key fatigue mechanisms include:
- Crack initiation and growth from cyclic tensile or compressive stresses
- Thermal fatigue due to repeated heating and cooling cycles
- Oxidation-assisted weakening of surfaces under fluctuating thermal and chemical loads
- Mechanical wear synergy, where abrasive particles accelerate fatigue damage under stress
Industries such as oil and gas, molten metal handling, and high-volume manufacturing are particularly vulnerable, as fatigue failures can lead to costly downtime and unplanned outages.
International Syalons offers a suite of sialon ceramics engineered to resist fatigue through superior mechanical resilience, thermal stability, and oxidation resistance. These materials are designed to operate in high-load, high-temperature environments without degradation over time.
- Fatigue limit ~700 MPa
- ΔT = 900°C
- Fatigue limit ~650 MPa
Engineered for Durability
The fatigue resistance of sialon ceramics is a direct result of their controlled microstructure and tailored chemistry:
- Grain Boundary Control: Low amorphous content minimizes creep and deformation under cyclic load
- Dual-Phase (α/β-SiAlON) Systems: Combine α-phase hardness with β-phase toughness to resist crack growth
- High Density (>99%): Prevents porosity-induced stress concentrations and premature failure
- Covalent Si-N Bonds: Provide exceptional stiffness and resistance to cyclic strain
Optional reinforcement with secondary phases (e.g., boron nitride) further enhances crack arresting capabilities and thermal fatigue strength in extreme applications.
Real-World Applications
International Syalons' fatigue-resistant ceramics have been deployed successfully in applications such as:
- Welding Rolls: Syalon 101 resists repeated thermal and mechanical loading, lasting up to 20× longer than steel equivalents
- Thermocouple Sheaths: Survive thousands of thermal cycles in molten aluminum environments with minimal degradation
- Oil & Gas Hydrocyclones: Maintain structural integrity despite constant pressure fluctuations and sand abrasion
Tested for Cyclic Reliability
Fatigue validation includes four-point bending tests at temperatures up to 1400°C and cyclic loads exceeding 10⁴ cycles. Sialon components consistently demonstrate

Contact our technical team to discuss fatigue-resistant materials tailored to your application.

Sialon and zirconia provide the high temperature strength and non-wetting properties necessary for metal casting, extruding, and welding.

Technical ceramics are characterised by excellent mechanical strength and hardness, and are widely used in extreme wear applications.

Silicon nitride offers excellent corrosion and thermal resistance and are ideal materials for use in the chemical and process industries.
