Impermeability in material testing is a concept that holds significant importance in a variety of industries, some being engineering, construction, and environmental science. From protecting our homes against water damage to safeguarding electrical components, low permeability is a vital characteristic we rely on daily.
In this guide, we provide real-world examples of impermeability in material testing and how practical applications ensure your final product is safe and reliable.
Join us as we explore what impermeability means in material testing and its impact on several industries.
What Does Impermeability in Material Testing Mean?
Impermeability refers to the quality or characteristic of a material that prevents the passage of substances. The physical property determines whether the material is impervious to gasses, liquids, or other substances attempting to permeate through it.
Testing impermeability is essential in many fields and applications. For example, you can use impermeable materials and coatings to prevent water intrusion and moisture damage to buildings. In packaging goods, impermeability ensures the products are preserved and contained from contaminants or hazardous substances.
There is specialized equipment designed for impermeability. One includes a concrete test device that uses the depth of water penetration to determine the pressure and strength of concrete.
Why is Impermeability in Material Testing Important?
Impermeability is crucial because it ensures the integrity, safety, and functionality of systems and materials. By using impermeable materials, you can prevent water damage, contaminant transfer, and perished goods. Blocking the permeation of substances, whether that’s liquid or gas, will make materials more reliable for your projects.
Safety and risk mitigation are also factors you must be aware of when testing the impermeability of materials. You should make systems or materials durable while also testing their strength against hazardous substances that could harm human health. An example includes nuclear power plants with impermeable barriers to control potentially dangerous materials.
Keep Reading: Core Drilling with Certified Material Testing Products.
8 Factors that Affect Impermeability in Material Testing
Understanding the factors that affect impermeable materials can help you choose the right resources and design considerations for your project. It’s important to note that the factors below may interact, and each factor can vary depending on the application method and material.
1. Material Properties
The inherent characteristics of materials usually determine the impermeability level. Factors such as pore distribution, density, surface texture, and chemical composition can impact how easily substances pass through.
For instance, impermeable rocks like marble and shale have smaller pores, meaning fluids cannot penetrate. The same goes for acrylic, polyurethane, and polyurea-based concrete since water and other fluids won’t pervade the surface.
You can use concrete testing equipment to determine whether the concrete foundation has low permeability.
2. Thickness
In general, thicker materials are more effective at blocking the passage of fluid and gas compared to thinner properties. You should consider diffusion path length and barrier effects when monitoring this factor.
Diffusion path length determines the distance a substance must travel to pass through the material. With thicker surfaces such as concrete and impermeable rocks, the diffusion path length increases, providing a greater barrier that inhibits the movement of molecules and particles.
More Read: Certified Thermometers for Material Testing.
3. Pressure
The impact of pressure on impermeability varies depending on its application, whether it is exerted internally, externally, or as a differential pressure. These pressure conditions influence the behavior of your material when it interacts with substances.
● External pressure: When applying external pressure on a system or material, it can enhance impermeability by increasing compressive strength and tightening the intermolecular gaps. The added pressure also acts as a force to seal porous substances and makes it challenging for a liquid to penetrate.
● Internal pressure: Subjecting a material or system to high internal pressure can have the opposite effect. Any pressure that overcomes the barriers and limitations of the material will lead to permeation or leakage. In turn, the material could rupture due to its increased permeable nature.
● Differential pressure: This condition refers to the difference between two sides of a material. High pressure can encourage a substance to penetrate through with lower resistance or through any defects. For example, significant pressure within a membrane or barrier can comprise its impermeability.
4. Temperature
Temperature changes can affect the material’s behavior, molecular structure, and physical properties, which may impact its impermeability. Molecules within the material could move rapidly at higher temperatures and leave gaps for a substance to infiltrate. The same goes for thermal expansion, in which materials expand in heat and reveal more hidden defects.
Other results, such as phase changes and chemical composition, rely on temperature. Any shift in the temperature could encourage phases like melting or solidification. Materials in a liquid state have more permeable properties. Elevated temperatures can also degrade the material or alter its composition when blocking a substance.
Therefore, using thermometers to check the material’s temperature is essential for maintaining its impermeability.
5. Humidity
Humid environments play a huge role in the impermeability of materials. High humid levels can introduce moisture that weakens the barriers, leading to a more permeable surface. Materials exposed to these settings could absorb water vapor, fostering swelling, softening, or changes in dimensional stability.
Moreover, humidity accelerates chemical reactions that degrade a material. Oxidation and corrosion are two culprits for increasing permeable properties. So, controlling and regulating humidity levels is essential for protecting your materials and ensuring their high-quality performance in long-term projects.
6. Chemical Compatibility
When your material comes into contact with chemicals, it can affect its structure, integrity, and impermeability. Chemicals such as acids, solvents, and oils, may react negatively with the material and cause degradation. Over time, this interaction will cause cracks and changes to the surface’s roughness, comprising the impermeable properties. Hence, it’s important to choose materials that are compatible with the chemicals they might encounter.
7. Mechanical Stress
Materials that are subjected to stress, whether that’s from stretching or bending, may become more permeable. This is because physical tension creates microcracks that encourage air, fluid, or gas to pass through. Any stress-induced changes could also weaken the material’s mechanical strength, which allows fractures to form as the material ages.
8. Age and Degradation
As materials age, they may experience physical, structural, or chemical changes that compromise their impermeability. Exposure to UV radiation, moisture, and temperature fluctuations will deteriorate any coatings and make the material more permeable. Regular maintenance with timely replacements ensures your projects are durable, especially if they’re exposed to harsh weather conditions and porous substances like chemicals.
How Can I Find the Best Equipment for Impermeability in Material Testing?
To ensure your materials are impermeable, use high-quality equipment from Certified MTP to gain accurate and reliable results. Our standardized tools can help you locate any defects or cracks through non-destructive evaluation, a technique that evaluates impermeable rocks and cement without causing damage.
Impermeability is a fundamental quality that keeps materials protected against water damage, contamination, and environmental erosion. By choosing resources with low permeability, you can form products that refuse the passage of air, fluid, or gas.
Contact us today to learn more about impermeable materials and how you could test them with our equipment
