IMR Materials Testing Technical Blog

4 Material Transformations Revealed by High-Temperature Fatigue Testing

Changes to both microstructure and performance can significantly alter material properties, and understanding how this occurs while exposed to elevated temperatures is crucial for many industries. Manufacturing, aerospace, and automotive industries, in particular, benefit from material knowledge in high-temperatures environments.

A specialized high-temperature fatigue test frame’s ability to expose the test specimen to temperatures up to 1800°F can replicate the operating conditions experienced by turbine blades in gas engines, power generating plants and jet engines.

Key transformations caused by exposure to high temperatures include:

1. Diffusion Processes

Diffusion at high temperatures occurs when atoms in a liquid, gas, or solid mix with the host solid on the atomic level, ultimately changing material composition and phase structures. These changes affect overall strength and durability.
Applications: Surface hardening, alloy production, heat treatment.

2. Aging

Aging is heating a solution-treated metal alloy to a temperature high enough to accelerate precipitation but below the recrystallization point. The controlled aging process can enhance mechanical strength and hardness, a vital process for manufacturing components with a high performance life.
Applications: Automotive parts, aerospace materials, strengthening aluminum alloys.

3. Dislocation Restructuring (Softening)

Also known as glide or slip, dislocation structuring happens when atomic dislocations allow atoms to slide over each other at lower stress levels. This phenomenon is common in plastics but can occur with certain metals. Crucial for applications requiring flexibility, the material’s ability to deform under stress without fracturing is critical.
Applications: Ductile materials, polymers, plastics.

4. Recrystallization

Recrystallization is the replacement of deformed grains in a material with new, defect-free grains. New grains nucleate and grow until they fully consume the original grain structure. Recrystallization can restore the ductility of metals after they have been hardened.
Applications: Ductile materials, polymers, plastics.

Thermal Stess and Surface Degradation

Thermal stresses caused by elevated temperatures can significantly reduce the longevity and reliability of components. High-temperature fatigue testing is essential to determine how materials will behave in extreme conditions to ensure they are suited for operating environments. Common effects of thermal stress and change in internal structure of the material include:
Pitting: Localized corrosion which causes small pits.
Micro-Pitting: Small scale pitting that leads to overall material weakening.
Scuffing: Surface damage due to wear and high friction.
Wear: Progressive loss of material.

Why High-Temperature Fatigue Testing is Critical

High-temperature fatigue testing allows engineers to determine favorable material characteristics for high-temperature environments, allow them to select materials that improve the safety and durability of final products. You can predict the fatigue life of materials in harsh conditions and ensure components maintain integrity under thermal stress and wear.

Understanding how materials react to elevated temperatures is critical for ensuring long-term performance and durability. IMR Test Labs offers comprehensive high-temperature fatigue testing services to help you identify the best materials for your specific application. Our team is equipped to deliver precise results tailored to your needs.

Contact IMR Test Labs today to learn how we can support your material testing and analysis requirements, ensuring your components perform reliability in even the harshest environments.

Learn more about  IMR Test Labs high-temperature fatigue testing capabilities.Footnotes1) Springer Link2) MetalSupermarkets.com3) Wikipedia4) Wikipedia