CNH MTM0126 Material Test Methods - 96 Hour Humidity Test, Paint Materials on Plastics

The “CNH MTM0126 Material testing methods - 96-hour moisture test, paint materials on plastics” standard, developed by CNH, an American-Italian multinational company , describes a test method for evaluating the ability of a cured paint material film on plastic parts to resist degradation from prolonged exposure to 100% relative humidity. This method can also be used to evaluate integrated colored plastic materials. For these materials, the test is designed to determine the effect of moisture on the surface appearance.

This test method may involve hazardous materials, devices, and procedures. This test method is not intended to address all safety issues associated with its use or application. It is the user's responsibility to consult appropriate, established safety or health practices and determine the applicability of regulatory limitations prior to use.

The testing process is as follows:

• To evaluate a paint material, at least two test samples must be subjected to this procedure.
• Representative test specimens are selected that have a smooth continuous surface and a test area free of evidence of poor film formation, sagging, solvent bursting, pinholes, and the like.
• The hardness of the test sample paint film is measured to determine the initial hardness prior to any harmful environmental exposure.
• Hardness and adhesion testing procedures are not required for integrally colored plastic materials.
• The surface of the test sample is visually inspected to identify any scratch marks, blemishes, or other surface defects. These should be noted prior to exposure to the test conditions. All waxes, oils, or other residue should be removed before testing using a cloth dampened with a warm soapy solution or organic solvent cleaner that is not harmful to the paint material.
• Scored the test sample as described in the CNH MTM0120 standard to create a test grid for the adhesion test.
• The test specimen is placed in a pre-conditioned room at 40°C plus/minus 2°C and 100% relative humidity. The relative humidity exposure cycle should be 96 hours.
• Test specimens exhibit water droplet formation on their surfaces during the exposure cycle due to condensation. Visual inspections of test specimens are performed every 24 hours. If no droplet formation is observed, 100 percent relative humidity is not being maintained, and the test is discontinued. The chamber door may be opened once a day (24-hour period) for an interval of less than 3 minutes to remove or inspect test specimens.
• At the end of the 96-hour test cycle, test samples are removed from the relative humidity chamber and dried with a lint-free cloth. Paint film evaluation is performed within ten minutes of removing the samples from the chamber.
• The sample surface is visually inspected and any discoloration, bubbling, or other deterioration is noted. The condition of the sample is recorded.
• The hardness of the test sample paint film is measured.
• The adhesion of the test sample paint film is evaluated as described in the CNH MTM0120 standard.

In short, the purpose of CNH MTM0126 is to evaluate the resistance of cured paint films on plastic components when exposed to extreme humidity conditions. This standard is designed to simulate 100 percent relative humidity at elevated temperatures for a period of 96 hours. This standard aligns with the methodology of ASTM D2247 Standard Practice for Testing Water Resistance of Coatings at 100 percent relative humidity and correlates with other CNH test standards, such as CNH MTM0120 for adhesion and CNH MTM0105 for general performance criteria.

The chamber used for the tests is a humidity chamber equipped with a heated water tank that maintains 100 percent relative humidity and a controlled temperature (approximately 40 degrees Celsius plus/minus 2 degrees Celsius). It contains shelves set at approximately 75 degrees Celsius to ensure condensation flow. Type IV water (e.g., reverse osmosis/distilled) is used. At least two painted plastic specimens meeting CNH MAT0105 standards are used in the tests (they must be cleaned, lint-free, and free of defects). The hardness is recorded using the pencil or pendulum method (ASTM D3363 or ASTM D4366 standards) before the test begins.

This standard ensures that plastic parts used in CNH's machines, such as tractors, excavators and loaders, maintain their paint durability when exposed to high humidity environments, preventing aesthetic deterioration or performance problems.

At its core, the CNH MTM0126 standard is a rigorous qualification process to ensure that painted plastic parts used in heavy equipment can withstand prolonged exposure to high humidity without losing their structural or aesthetic qualities.

The CNH MTM0126 standard is widely used in various industries, particularly the automotive and heavy machinery sectors. This standard is considered important for the following reasons:

• Ensures durability in harsh environments: CNH equipment (tractors, loaders, excavators) often operates in damp, muddy, and extreme outdoor conditions. This standard simulates long-term exposure to high humidity to verify that paint coatings on plastic components do not:
  • Peeling
  • Blistering or blistering
  • Discoloration
  • Loss of adhesion

This helps ensure the long-term cosmetic and functional integrity of painted plastic parts.

• Protects against corrosion and deterioration: While plastics do not corrode like metals, their coated surfaces can deteriorate due to trapped moisture. If the paint system fails:
  • The plastic may become brittle or crack.
  • UV and chemical resistance may decrease.
  • Mechanical parts may become exposed or weakened.

This standard ensures that the coating remains a protective barrier.

• Supports quality assurance in production: By implementing this standard, the following can be achieved:
  • Can compare different paint formulas.
  • Can validate new materials or coatings.
  • It can detect problems in the painting or curing process.
  • It can ensure consistent quality in global production lines.

It becomes a critical quality control point before the product is released to market.

• Increases customer satisfaction and brand reputation: A machine with fading, peeling, or blistering paint appears worn or poorly built, even if it is structurally sound. Consistent performance in humid conditions:
  • Maintains its visual appeal.
  • It reflects high construction quality.
  • Reduces warranty claims and repainting costs.

It directly contributes to user trust and brand loyalty.

• Aligns with industry best practices: This standard is based on globally recognized testing procedures such as ASTM D2247, which aligns CNH's internal standards with broader industry expectations. This helps:
  • Facilitates supplier qualification.
  • Enables cross-comparison with other original equipment manufacturers.
  • It promotes global standardization and benchmarking.

Our organization, which has been supporting businesses across all sectors for years through a wide range of testing, measurement, analysis, and evaluation activities, has a strong team of employees who closely follow global developments in science and technology and are constantly improving themselves. In this context, we also provide testing services in accordance with the "CNH MTM0126 Material Testing Methods - 96-Hour Moisture Test, Paint Materials on Plastics" standard.