Falling Dart Impact Tests:

The falling dart impact test is a rapid method for evaluating impact toughness of plastics, especially films and sheets. The test uses a dart dropped from one of two different heights depending on the method chose. The weight of the dart can also be varied.

The falling dart impact test data can be used for:

• quality control,
• inspection of incoming parts, 
• failure analysis,
• comparison of suppliers,
• adjustment of production and additive settings, 
• research and development of film and sheet products, 
• or other end-user purposes. 

Falling Dart Test Procedure:
The expected impact strength is used to dictate which test method is chosen: Method A utilizes a 26″ (0.66 meters) drop height with 1.5″ dart and Method B utilizes a 60″ (1.52 meters) drop height with 2″ darts. Test samples are impacted to determine the appropriate starting weight of the dart. Test samples are clamped at the base of the drop tower, and a dart is inserted into the testing bracket. The dart is then released onto the center of the test specimen, and then test results (pass/fail) is recorded along with the weight of the dart. 

The ‘Bruceton Staircase’ process is used to evaluate the data, typically using a series of 20+ impacts. When the specimen passes, the drop weight is increased, and vice versa when it fails. The results are used to calculate the ‘Impact Failure Weight’, which is the calculated weight for which 50% or more of the test specimens will fail under the impact at a given height. 

Specimens:

The testing specimens are cut to a size of 250 x 250 mm or smaller (approximately 10″ x 10″) . At least 30 specimens are requested, so either 25′ x 10″ or pre-cut sheets are acceptable if packed appropriately. 

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