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Material Testing

What grip face should I use with my sample?

Serrated/Pyramid faces for clamping plastics and soft materials. also called ‘pyramid’, Pyramid jaws are universally used for notch-insensitive samples like, e.g., metal, wood, plastics, gypsum, etc. Rubber coated are used for relatively fragile samples weakened by pinching at the edge of the grip face - monofilaments, wire, film, single fibers, and aluminum. threads, fabrics, and plastic tapes. Rubber jaws are universally applicable for soft notch-sensitive samples like, e.g., paper, foils, cellulose, etc. Smooth Jaws – for smooth surfaced materials. thin sheets, films, foils, paper and tapes Diamond Grit – aggressive surface for soft steels, rigid plastic and wood. ‘diamond cut’...

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Measuring Uncertainty - Force Testing Made Easy

Uncertainty is among the many variables that need to be considered when performing force testing. Uncertainty results from a combination of factors, including errors that may affect the outcome of tests. And, while many errors may be cumulative, as long as the variables are predictable, the test measurements should still be correct.Without going into complex uncertainty calculations, the following article looks at common force testing situations and offers practical examples of how to clarify force testing uncertainty. A body scale, for example, indicates weight with an accuracy of ±1 pound. If a person weighs 100 pounds, then the true weight...

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De-lamination Strength Testing

De-lamination is the separation of the layers in a laminate. Laminate is a sheet of material that has been created by stacking thin layers, or plies, and bonding them together. De-lamination can occur locally, in a small area of the laminate, or it can affect the entire laminate. In laminated materials, repeated cyclic stresses, impact, and so on can cause layers to separate, forming a mica-like structure of separate layers, with significant loss of mechanical toughness. A wide range of structural applications are possible; however, amongst other considerations the performance of these materials under crash and impact loading is a...

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