ASTM D5672 Standard Test Method for Testing Flexible Cellular Materials: Measurement of Indentation Force Deflection Using a 25-mm [1-in.] Deflection Technique

Get Certified ASTM D5672

Standardized testing laboratories use methods to evaluate flexible polyurethane foam cushions to ensure that certified laboratories certify them correctly. Manufacturers use experienced laboratory testing to ensure foam cushions meet the firmness grade requirement range. ASTM D5672 certified testing supports quality control, production screening, and product development for foam-based applications. Professional laboratory services help ensure adherence to standards and build confidence in test results. In order to avoid quality problems, quality control engineers employ certified testing to improve foam firmness.

• Measures the deflection caused by indentation force in flexible cellular materials that are flexible.
• Tests foams for firmness to determine whether they fall within the specified firmness range.
• Applies to foams 75 mm [3 in.] or thicker. Uses a standard thickness of 100 mm [4 in.] as per industry convention. 
• Makes use of 25 % deflection (25 mm [1 in.] on regular cushions).
• Provides a rapid, simple screening method for production quality control.
• Helps determine the firmness grade of flexible polyurethane foams. 

What are the Uses of ASTM D5672Testing?

Manufacturers use ASTM D5672 testing to help determine firmness grades for flexible polyurethane foam cushions. Manufacturers use test results for quality control, production screening, and product development. Manufacturers apply the standard widely in foam manufacturing, furniture, automobile, and bedding industries. This standard-

• Tests the softness of flexible polyurethane foams for firmness grade.
• Maintains uniform foam quality in production.
• Assists with quality control for foam production.
• Assists in establishing whether or not foam cushioning conforms to specifications.
• Provides a rapid, easy test procedure.
• Minimizes the risk of out-of-specification products.
• Assists in the formulation and development of products. 

Which materials can be tested under D5672?

ASTM D5672 applies to flexible cellular materials, flexible polyurethane foam cushions. The test method is used for foams that measure 75 mm  [3 in.] or more in thickness. The method is recommended for production screening and quality control of full-size cushions. To obtain reliable test results, the correct sample and sample conditioning are critical. 

Why is ASTM D5672 Important? 

ASTM D5672 is a standard method for determining indentation force deflection of flexible cellular materials. The test method provides guidelines and testing conditions to assist manufacturers in determining whether the foam cushion falls within the specified firmness grade range. The standard guarantees uniformity of test procedures and interpretation of test data. Quality control engineers use these results to ensure consistent foam firmness and prevent quality issues. The fast and easy screening process facilitates effective production quality control. 

ASTM D5672 Testing Process and Data Collection

The testing process begins with conditioning the foam sample as per standard requirements. Technicians verify foam thickness meets the minimum requirement of 75 mm [3 in.]. They position the inner foot on the foam surface. They apply force to indent the foam by 25 mm [1 in.] and measure the force required. They record the indentation force deflection value. They compare the value with the specified firmness grade range. Laboratories collect data for quality control, production screening, and product development purposes.

Common Challenges and Troubleshooting

Typical problems that arise with ASTM D5672 testing include inadequate specimen preparation, inappropriate foam thickness, and inaccurate force readings. These issues impact the accuracy of the determination of IFD grades. If not properly conditioned, test results can vary. If the thickness of the foam is less than 75 mm (3 in.), the test is invalid. The force measurement may be wrong, leading to an incorrect grade classification. Proper specimen conditioning, foam thickness verification, and regular equipment calibration minimize problems. Reliable results are provided by experienced technicians who know how to use the equipment properly and follow standard operating procedures.

• The laboratory reports the indentation force deflection (IFD) value as the force required to produce the specified 25 mm [1 in.] deflection, with force reported in N or lbf.
• The analyst compares the measured IFD value with the specified grade or firmness range to determine whether the foam meets the applicable requirements.
• The laboratory records the specimen and test conditions, including the specimen dimensions, conditioning conditions, and specified deflection used for the measurement.
• The quality-control engineer evaluates the measured IFD value against the applicable requirements and reports the result as Pass or Fail when the specification provides such acceptance criteria.

What Factors Should You Consider for ASTM D5672 Testing?

To obtain reliable results, ensure the lab prepares specimens consistently, properly conditions them, and uses calibrated equipment. Consider the following when choosing a lab for this testing.

• Expertise: Skilled technicians should select the right procedure, prepare specimens, operate equipment, and analyze the results. 
• Speed: Testing time depends on the number of properties evaluated and the specimen preparation requirements for each procedure. 
• Cost: Testing costs depend on the number of properties tested, specimen preparation, equipment requirements, and the complexity of the testing program.
• Confidentiality: Matestlab maintains complete confidentiality in the testing process, and results are carefully disclosed to the respective stakeholders only.

Link to ASTM D5672