Mercedes-Benz DBL 5474 Polyamide 6 (PA6) - Heat-Resistant, Glass Fiber Reinforced

The “Mercedes-Benz DBL 5474 Polyamide 6 (PA6) - Heat-resistant, glass fiber reinforced” standard, developed by the Mercedes-Benz Group, describes the requirements for glass fiber reinforced, heat-resistant polyamide 6 (PA6-GF) used in Daimler automotive parts. This standard includes mechanical, thermal, and environmental properties to guarantee material consistency and performance.

Heat-resistant, glass-fiber-reinforced refers to specific modifications made to a plastic material, often used in engineering plastics such as Polyamide 6 (PA6), to improve its performance in demanding applications such as automotive components. Here's what each term means:

Heat-stabilized (heat-resistant) means the plastic has been chemically modified to resist degradation at high temperatures over time. This is typically achieved through additives such as antioxidants or thermal stabilizers. Without stabilization, polymers like PA6 can degrade when exposed to heat, such as in engine compartments, leading to discoloration, loss of strength, brittleness, or failure. For heat-stabilized PA6, long-term use at temperatures between 120°C and 150°C is common, depending on the formulation.

Glass fiber reinforcement means that short glass fibers are mixed into the plastic during production to increase its mechanical strength and stiffness. This process increases tensile strength, hardness, and dimensional stability. It also improves resistance to friction (deformation that occurs over time under load). It also reduces thermal expansion, making the material more stable under temperature changes. Common glass content typically ranges from 15 to 50 percent by weight, with higher content offering greater reinforcement.

As for the combined effect of being heat-stabilized and glass fiber reinforced: when a plastic is both heat-stabilized and glass fiber reinforced, it becomes suitable for use in high-performance applications such as:

• Engine covers
• Air intake manifolds
• Radiator end tanks
• Structural automotive parts

This combination allows the material to maintain its shape, strength and performance even under high temperatures and mechanical stress.

Polyamide 6, commonly known as PA6 or nylon 6, is a semi-crystalline thermoplastic polymer. It is part of the polyamide family and is widely used in engineering applications due to its excellent mechanical, thermal, and chemical properties.

The main properties of Polyamide 6 (PA6) are as follows:

• High mechanical strength: Strong and durable, especially when reinforced with glass fibre. Provides excellent impact resistance and tensile strength.
• Good wear and abrasion resistance: Ideal for parts subject to friction or mechanical wear (e.g. gears, bushings).
• Heat resistance: can work continuously at about 100 degrees to 120 degrees. Heat-resistant grades can handle higher temperatures.
• Chemical resistance: Resistant to many oils, fuels and solvents. Not resistant to strong acids and some bases.
• Moisture absorption: Hygroscopic, absorbing water from the air, which can affect dimensions and mechanical properties. Water absorption can actually increase toughness but decrease hardness.

Common applications of polyamide 6 include:

• Automotive parts (e.g. radiator components, housings, engine covers)
• Electrical and electronic enclosures
• Consumer goods (electrical tool cases, furniture parts)
• Industrial parts (gears, bearings)

The Mercedes-Benz DBL 5474 standard defines technical requirements to guarantee quality, safety, and compatibility for materials and components used in its vehicles. This standard typically includes the following:

• Material composition:
  • Polyamide 6 (PA6)
  • Glass fiber content (e.g. 15 percent, 30 percent)
  • Heat stabilizers for long-term thermal resistance
• Mechanical properties:
  • Tensile strength
  • Impact resistance
  • Elasticity modulus
• Thermal properties:
  • Heat deflection temperature
  • Heat aging performance
• Environmental resistance:
  • Resistance to moisture, oil and fuels
  • Dimensional stability under humidity and heat
• Colour, appearance and surface quality:
  • Often includes aesthetic requirements for visible parts
• Test methods and criteria
  • Specifies the international standard tests that should be used to qualify materials

For years, our organization has been supporting businesses from all sectors with a wide range of testing, measurement, analysis, and evaluation services. We have a strong team of employees who closely follow global developments in science and technology and continuously improve themselves. Within this framework, we also provide testing services in accordance with the "Mercedes-Benz DBL 5474 Polyamide 6 (PA6) - Heat resistant, glass fiber reinforced" standard.