libmatt.com Silicone offers excellent flexibility and high-temperature resistance, making it ideal for applications requiring durability in extreme environments. FKM provides superior chemical resistance and mechanical strength, ensuring your seals and gaskets perform reliably in aggressive fluids and harsh conditions.
Table of Comparison
| Property | Silicone | FKM (Fluoroelastomer) |
|---|---|---|
| Temperature Resistance | -60degC to 230degC | -20degC to 200degC |
| Chemical Resistance | Good against ozone and weathering; poor against oils and fuels | Excellent resistance to oils, fuels, and chemicals |
| Flexibility | High flexibility at low temperatures | Moderate flexibility |
| Durability | Moderate abrasion resistance | High abrasion and wear resistance |
| Cost | Lower cost | Higher cost |
| Common Applications | Medical, food, seals with high temperature exposure | Automotive, aerospace, chemical processing seals |
Introduction to Silicone and FKM
Silicone and FKM (fluoroelastomer) are high-performance elastomers used in sealing and gasket applications, each offering distinct chemical and thermal resistance properties. Silicone excels in flexibility and temperature stability, functioning effectively between -60degC and 230degC, while FKM provides superior resistance to fuels, oils, and aggressive chemicals, withstanding temperatures up to 250degC. Understanding the differences between Silicone and FKM helps you select the ideal material to ensure optimal performance and durability in your specific industrial or automotive applications.
Chemical Composition and Structure
Silicone is a synthetic polymer composed primarily of silicon, oxygen, carbon, and hydrogen atoms forming a flexible, linear siloxane backbone that provides excellent thermal stability and chemical inertness. FKM, also known as fluoro rubber, contains vinylidene fluoride and hexafluoropropylene monomers, resulting in a highly fluorinated carbon chain structure that offers superior resistance to oils, fuels, and aggressive chemicals. Your choice between Silicone and FKM depends on the specific chemical environment and temperature range required for optimal performance.
Temperature Resistance Comparison
Silicone offers excellent temperature resistance, typically performing well in a range from -60degC to 230degC, making it suitable for high-heat applications like automotive engine seals or food-grade gaskets. FKM (fluoroelastomer) exceeds silicone's capabilities with a higher continuous service temperature range, usually between -26degC and 250degC, and exceptional resistance to extreme heat and chemical degradation. Your choice depends on whether you need flexibility at low temperatures (favoring silicone) or superior chemical and heat resistance for demanding industrial environments (favoring FKM).
Mechanical Properties and Durability
Silicone offers excellent flexibility and resistance to extreme temperatures, making it ideal for applications requiring consistent elasticity and durability in harsh environments. FKM, or fluoroelastomer, provides superior chemical resistance and mechanical strength, particularly against oils, fuels, and solvents, ensuring longevity in aggressive conditions. Your choice between silicone and FKM should consider the specific mechanical stresses and environmental exposure to maximize performance and service life.
Chemical Resistance: Silicone vs FKM
FKM (fluoroelastomer) exhibits superior chemical resistance compared to silicone, effectively withstanding strong acids, oils, fuels, and aggressive solvents. Silicone resists oxidation, ozone, and extreme temperatures but is vulnerable to certain chemicals such as ketones and hydrocarbons. Your choice depends on the specific chemicals involved; FKM is ideal for harsh chemical environments, while silicone suits milder conditions with excellent thermal stability.
Common Applications of Silicone and FKM
Silicone is commonly used in medical devices, food contact applications, and automotive seals due to its excellent temperature resistance and biocompatibility. FKM (fluoroelastomer) is preferred in chemical processing, aerospace, and fuel system components for its superior chemical resistance and durability in harsh environments. Your choice between Silicone and FKM depends on specific performance requirements such as temperature tolerance, chemical exposure, and mechanical stress.
Cost Differences and Availability
Silicone is generally more affordable and widely available compared to FKM, making it a cost-effective choice for many applications. FKM offers superior chemical resistance and high-temperature performance but comes at a higher price point and limited availability. Your decision should weigh the budget constraints against the specific performance needs of your project.
Advantages of Silicone Over FKM
Silicone offers superior temperature resistance, maintaining flexibility in extreme cold and withstanding continuous exposure to temperatures up to 230degC, which often surpasses the limits of FKM elastomers. It provides excellent biocompatibility and resistance to UV light, ozone, and weathering, making it ideal for medical and outdoor applications. Your choice of silicone can ensure long-lasting performance and durability in environments where chemical resistance and flexibility are critical.
Advantages of FKM Over Silicone
FKM (fluoroelastomer) offers superior chemical resistance compared to silicone, making it ideal for use in aggressive environments with fuels, oils, and acids. Its exceptional thermal stability allows FKM to maintain performance in continuous temperatures up to 200degC, outperforming silicone's lower thermal threshold. FKM also exhibits superior mechanical properties such as abrasion resistance and low gas permeability, enhancing its durability in demanding industrial applications.
Choosing the Right Material for Your Needs
Silicone offers excellent temperature resistance from -60degC to 230degC and outstanding flexibility, making it ideal for applications requiring durability and biocompatibility. FKM (Fluoroelastomer) provides superior chemical resistance, especially against fuels, oils, and aggressive solvents, and performs well in temperatures ranging from -20degC to 200degC. Selecting between Silicone and FKM depends on your specific environmental conditions, such as exposure to chemicals, temperature extremes, and mechanical stress.
Silicone vs FKM Infographic
