Nissan NES M8020 Chemical Resistance Test Methods for Plastic Parts

The standard "Nissan NES M8020 Chemical Resistance Test Methods for Plastic Parts," developed by Nissan Automobiles, describes test methods for the chemical resistance of plastic parts used in automotive components. These methods are intended to determine whether chemicals used in dealerships and during vehicle and component assembly processes cause abnormalities in automotive plastic parts. These abnormalities include dissolution, clouding, staining, discoloration, deformation, cracks, fractures, thinning, softening, hardening, and similar abnormalities caused by direct contact of the part with chemicals or by chemicals in adjacent parts. For plastic materials used in automotive components, this standard also specifies a method for assessing aging deterioration due to chemical changes resulting from continuous contact with chemicals.

Test methods are divided into six types, depending on the location and type of exposure of the part, as shown in the table titled "Test method classification." Depending on the location of the part, more than one test method should be applied, if applicable. The selection of chemicals to be tested should fully consider the environments in which each part will be used. However, not all chemicals specified in this standard need to be tested.

• Method 1 Type 1: Applied to parts used as containers or equivalent. This is an immersion method. It is expected to be resistant to all chemicals used in containers.
• Method 1 Type 2: Applied to parts normally exposed to chemicals. This is an immersion method. It is expected to resist all chemicals that come into contact with the part.
• Method 2: Applied to internal parts. This is a wiping method. It is expected to resist artificial perspiration, detergents, insect repellents, suntan oil, sunscreen, liquid paraffin, and similar chemicals.
• Method 3: Applied to exterior parts. This is a drip method. It is expected to resist gasoline, diesel fuel, kerosene, motor oil, acids, polishes, windshield washer fluid, detergents, primers, and similar chemicals.
• Method 4: Applied to parts inside the engine compartment. This is a drip method. It is expected to resist gasoline, diesel fuel, engine oil, kerosene, acids, brake fluid, antifreeze, windshield washer fluid, corrosion inhibitors, calcium chloride, and similar chemicals.
• Method 5: Applied to interior parts, exterior parts, and parts made of ABS, PMMA, PC, PPE, and PAT materials. This method is applied to a real vehicle. It is expected to resist grease, lubricating oil, metal cutting oil, press machine oil, anticorrosives, silicone oil (including emulsion types), paint protectants, paint strippers, mold release agents, detergents, artificial perspiration, and similar chemicals used during the part assembly process, vehicle assembly process, or dealership handling. When applied to parts adjacent to components containing plasticizers, it is expected to resist plasticizers (vinyl chloride, rubber materials) and similar chemicals.
• Method 6 (environmental load input test method): This is applied separately to parts that come into contact with or may come into contact with chemicals. This is an application or immersion method. Applicable parts are expected to demonstrate resistance to the chemicals they come into contact with or may come into contact with.

The test environment conditions were determined as follows.

• Room temperature conditions: The room temperature and humidity of the test location should be maintained in accordance with JIS Z 8703 standard Class 5 (temperature 20 degrees plus/minus 5 degrees) and Class 20 (relative humidity 65 percent plus/minus 20 percent) standards, respectively.
• Standard conditions: The standard temperature and humidity conditions of the test location should be provided in accordance with the JIS Z 8703 standard Class 2 (temperature 20 degrees plus/minus 2 degrees) and Class 10 (relative humidity 65 percent plus/minus 10 percent) standards, respectively.

In short, the Nissan NES M8020 standard ensures that thermoplastics, critical components in vehicle manufacturing, meet stringent quality, durability, and performance requirements. This standard focuses on evaluating the physical properties of thermoplastics, such as tensile strength, impact resistance, hardness, and thermal stability. Some of the key tests defined in the Nissan NES M8020 standard include:

• Tensile test: The purpose of this test is to determine the tensile strength, elongation, and modulus of elasticity of thermoplastic materials. Test specimens are prepared to specified dimensions and subjected to a controlled tensile force until they fail.

Key metrics include:

• Tensile strength: The maximum stress a material can withstand before breaking.
• Elongation at break: The degree to which the material elongates before breaking.
• Modulus of elasticity: The stiffness of the material under tensile stress.

This test ensures that thermoplastics used in structural components can withstand mechanical stresses without deforming or breaking.

• Impact testing: The purpose of this test is to evaluate a material's resistance to sudden impacts by simulating real-world conditions such as a collision or drop. Tests such as the Izod or Charpy impact tests, which measure energy absorption by striking a notched specimen with a pendulum, are used.

Key metrics include:

• Impact strength: The energy a material absorbs before breaking.
• Fracture behavior: Whether the material exhibits brittle or ductile failure.

This testing is critical for components that must absorb impact without causing catastrophic damage, such as bumpers or interior panels.

• Hardness testing: The purpose of this test is to determine a material's resistance to indentation or surface deformation. Tests such as Shore hardness or Rockwell hardness are performed using standard equipment to measure a material's surface resistance to penetration.

Key metrics include:

• Hardness value: Indicates the suitability of the material for applications requiring scratch or abrasion resistance.

This test is applicable to interior thermoplastics such as instrument panel surfaces that require resistance to wear and tear.

• Thermal stability testing: The purpose of this test is to evaluate the performance of the material under varying temperature conditions by simulating automotive environments from extreme hot to cold.

Key metrics include:

• Heat deflection temperature: The temperature at which a material deforms under a given load.
• Thermal expansion: The degree to which a material expands or contracts with temperature changes.

This testing ensures that thermoplastics maintain their structural integrity in engine compartments or extreme weather conditions.

• Chemical resistance testing: The purpose of this test is to evaluate how well thermoplastics withstand exposure to automotive chemicals such as oils, fuels, or cleaning agents. Samples are exposed to specific chemicals under controlled conditions, as specified in standards such as Nissan NES M0133 or Renault Nissan D49 3253.

Key metrics include:

• Chemical stability: The material's resistance to deterioration or discoloration.
• Surface integrity: No cracks or swelling after exposure.

This testing is critical for components exposed to fuels, lubricants, or cleaning agents, such as fuel system parts or exterior trim.

The Nissan NES M8020 standard specifies standardized conditions to ensure repeatable and comparable results. Key considerations include:

• Specimen preparation: Test pieces must be of exact dimensions and free from defects. For example, tensile test specimens may conform to ASTM D638 Type I dimensions (165 mm long, 3,2 mm thick).
• Environmental controls: Tests are performed under controlled temperature, humidity, and pressure to simulate real-world conditions or accelerate aging.
• Equipment: To meet the specifications of the standard, calibrated testing machines are required, such as universal testing machines for tensile tests or environmental chambers for thermal tests.

This standard ensures that thermoplastics meet performance requirements by providing clear criteria for pass/fail results. For example:

• To ensure structural integrity, tensile strength must exceed the minimum threshold.
• To ensure safety, impact resistance must meet certain energy absorption levels.
• Chemical resistance tests should not show significant degradation or deformation after exposure.

Thermoplastics tested under the Nissan NES M8020 standard are used in a variety of automotive components, including:

• Interior parts: Instrument panels, door panels and consoles where hardness and chemical resistance are critical.
• Exterior parts: Bumpers, grilles, and fender liners requiring impact resistance and weather resistance.
• Under-hood components: Parts exposed to high temperatures and chemicals, such as air intake manifolds or battery compartments.

As a result, the Nissan NES M8020 standard provides a comprehensive framework for testing the physical properties of thermoplastics used in automotive applications. Through rigorous tensile, impact, hardness, thermal, and chemical resistance tests, the standard ensures that materials meet the high performance demands of modern vehicles. By adhering to this standard, Nissan and its suppliers can deliver durable, safe, and reliable components that enhance vehicle performance and longevity.

Our organization, which has been serving for many years and meticulously following global developments in science and technology, employs a skilled team and extensive infrastructure to conduct testing, measurement, and analysis in a wide range of areas for businesses across all sectors. In this context, we also provide testing services in accordance with the Nissan NES M8020 Chemical Resistance Test Methods for Plastic Parts standard.