CRACKING
The Problem: Thermal and Mechanical Stress-Induced Failure
Cracking in industrial components is a frequent and costly mode of failure, particularly in systems exposed to rapid temperature fluctuations, repeated mechanical impacts, or long-term thermal loading. Conventional ceramics often lack the fracture toughness or thermal shock resistance to withstand these conditions, making them vulnerable to catastrophic brittle failure.
Primary cracking challenges include:
- Thermal shock: Sudden temperature differentials induce internal stresses that exceed material strength
- Mechanical impact: Forceful collisions in grinding, media milling, or handling can trigger brittle fracture
- Oxidation-related damage: Surface degradation in high-temperature oxidative environments initiates cracking
- Porosity-related flaws: Microscopic voids act as stress concentrators and crack initiation points
- Stress corrosion cracking (SCC): A failure mechanism where metals crack due to the combined effects of tensile stress and a corrosive environment, often occurring without significant deformation
International Syalons offers advanced ceramic materials specifically engineered for high fracture toughness, low thermal expansion, and exceptional thermal shock resistance, minimizing the risk of fissures and cracks even in the most demanding conditions.
- Thermal shock ΔT = 900°C
- Stable at 1200°C
- Thermal shock ΔT = 600°C
- Operates up to 1450°C
Microstructural Engineering for Crack Prevention
Sialon materials are designed to mitigate crack formation and propagation through several engineered features:
- Grain Boundary Engineering: Elongated β-SiAlON grains deflect cracks, increasing energy required for propagation
- High Density (>99%): Minimizes internal flaws and pores that act as stress concentrators
- Hybrid Composites: Boron nitride additions improve oxidation resistance and enhance thermal shock performance
- Low Thermal Expansion: Reduces the stress differential during rapid heating and cooling cycles
These features allow sialon ceramics to perform reliably under high stress, both mechanical and thermal, where other ceramics fail.
Application-Focused Solutions
International Syalons provides materials tailored to real-world component requirements:
- Thermocouple Sheaths: Syalon 101 resists cracking during molten metal immersion and rapid temperature cycling
- Grinding Media: Syalon 050 balances hardness and toughness to resist fracturing and particle shedding
- Vortex Finders & Hydrocyclones: Optimized geometries combined with crack-resistant materials ensure integrity under high flow and particle impact

Contact us today to explore which ceramic solution best fits your crack-prone 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.
