ASTM D1790 Standard Test Method for Brittleness Temperature of Plastic Sheeting by Impact

Get Certified ASTM D1790 Brittleness Temperature Testing

ASTM D1790 testing helps manufacturers, suppliers, and users assess the low-temperature impact behavior of plastic sheeting. Laboratories prepare specimens to the specified dimensions, condition them at controlled temperatures, apply the required impact, and record the failure response. The resulting brittleness temperature enables engineers to compare plastic materials, production batches, formulations, and processing conditions when low-temperature impact resistance is a critical performance requirement.

• Plastic Sheeting: Technicians condition plastic sheeting specimens at controlled low temperatures and apply the specified impact to determine whether the material develops brittle cracking or failure.
• Low-Temperature Performance: The temperature at which the plastic transitions between impact-resistant and brittle failure, which can be used by engineers to help decide the performance of the plastic in cold environments. 
• Impact Resistance: Imposes a controlled impact on conditioned specimens and reports if the material cracks or breaks under the test conditions and impact. 
• Material comparison: Engineers can use the brittleness temperatures to compare different plastic formulations, materials, and production batches for low-temperature performance. 

What are the uses of ASTM D1790 Testing?

This standard testing provides low-temperature impact data for plastic sheeting and helps manufacturers and engineers evaluate material performance under cold conditions. The ASTM D1790 test method-

• Determines the brittleness temperature of plastic sheeting. 
• Compares the low-temperature impact resistance of different plastic materials. 
• Supports quality control by identifying variation between production batches. 
• Helps engineers evaluate material formulations and processing conditions. 
• Supports material selection and product development for applications exposed to low temperatures. 

Which Materials Can Be Tested According to ASTM D1790?

ASTM D1790 focuses on applicable plastic sheeting materials for which low-temperature impact resistance is an important performance characteristic. Laboratories should confirm the material type, specimen requirements, and applicable test conditions before testing. The following materials can be tested with the ASTM D1790 test method-

• Plastic Sheeting: Evaluates applicable plastic sheeting for brittle impact failure at low temperatures. 
• Flexible Plastic Sheets: Evaluates applicable flexible plastic sheets where low-temperature impact resistance is relevant. 
• Different Plastic Formulations: Compares materials with different formulations or processing conditions to identify differences in brittleness temperature.

Why is ASTM D1790 Testing Important?

As the temperature drops, plastic materials can become hard and lose impact resistance. ASTM D1790 offers a method that is standard for measuring the brittle impact failure susceptibility of plastic sheeting. The results assist manufacturers and engineers in comparing materials, considering changes in formulation and processing, monitoring the quality of production, and determining if a plastic sheet is able to meet the specified cold temperature requirements.

ASTM D1790 Testing Process and Data Collection

Technicians first prepare representative plastic sheeting specimens and verify their dimensions and condition. They load the specimens into the controlled low-temperature system and wait until they have reached the target test temperature. The lab then applies the chosen impact to the conditioned samples and notes if they crack or break. Technicians record the test temperature, specimen type, specimen response to impact, and failure observations, then use these data to calculate the brittleness temperature.

Common Challenges and Troubleshooting

Variations in specimen thickness, preparation, temperature, conditioning, apparatus problems, and specimen defects may change the brittleness temperature measured. Before impact testing, technicians should prepare uniform specimens, check the temperature-control system, and ensure the same conditioning conditions for all specimens. Laboratories should also check the impact apparatus and confirm its proper functioning before testing. Technicians should note if the fracture is unusual or if the specimen has conditions that would impact the result.

• The laboratory report includes the following: brittleness temperature (ºC), specimen dimensions (mm), specimen thickness (mm), conditioning temperature (ºC), specimen impact response, specimen identification, and failure observations.
• The test establishes the temperature at which plastic sheeting is prone to brittle impact failure under the specified test conditions. 
• Engineers use brittleness temperature tests to compare the performance of plastic materials, formulations, manufacturing processes, and production batches for low-temperature performance. 
• Engineers use the test results for material qualification, quality assurance, product development, material comparison, and evaluation of plastic sheeting for cold-temperature applications.
• The results are interpreted in conjunction with specimen thickness, specimen condition, temperature, conditioning time, impact conditions, and failure characteristics, as these can affect the measured brittleness temperature. 

Link to ASTM D1790