Bent Lamination Strength Testing

When the sound hits a barrier such as air it will bounce back towards the probe.

Bent lamination strength testing.

The standard test specimen is 5 5 long and 1 5 wide with a specified thickness in the range of 0 125 to 0 208. Lamination bond strength the lamination bond strength of flexible laminates is determined in accordance with astm f904. After initiating de lamination between the relevant film plies the average force required to peel the two legs of the test piece is recorded. The trend is initially linear changing to a quadratic mode at longer time periods.

The test involves a measurement to determine the strength of a laminate s bond to a substrate material. This test covers the determination of the peel resistance of adhesive bonds between a relatively flexible adherent and the relatively flexible facing of a sandwich structure and its core. A 1 4 diameter pin or fastener is used. Figure 1a peel strength profile sample showing specimen cutouts and test results for geocomposite across the roll width.

It is equal to the tensile load applied divided by the sample width multiplied by the sample s thickness. This simple test fixture is shown in fig. 6 3 at least three test specimens printed with a test image and subsequently laminated. I ve got a few bent lamination items that i made with titebond 2 a few years ago that have stood the test of that much time no problems.

Depending on the coating and substrate. Test specimens 7 1 the substrate method of printing ink or toner lay down. The astm probe gave higher puncture values than the hemispherical probe. It has been my experience that the amount of spring back is influenced by the number of laminates thickness of the laminates species of wood cut of the grain plain sawn quarter sawn etc type of glue.

Richard thiel feature. The two halves of the fixture are separated by a spacer not provided of the same thickness as the specimen being tested. Application a climbing drum test is a typical peel testing method used to determine the de lamination characteristics of adhesives used to bond different materials together. Strength of cured laminates did not show any corresponding change for different percent loading of additives.

I have done a great deal of bent wood laminations over the years for circular stair handrails and to my knowledge no such formula exists. Time for an update. Ultrasonic testing ut uses high frequency soundwaves to detect laminations in the body of steel material. I researched and while there were suggestions that pva can creep there weren t any in depth studies proving it not with newer pvas anyway that i could find.

No delamination no creeping sliding. The puncture strength showed a gradual increase over a time period of 4 to 4 5 hours. In ut a probe sends a sound wave into the material. Purpose when the adhesive used is.

August 1st 2018 by. Geocomposite lamination strength astm test method. All photographs and graphs courtesy of the author.