Hole Accuracy in Micro Machining Test Sockets

Tensile Elongation at Yield (ASTM D638) is a property developed to measure the elastomeric limitations of polymers. The test essentially measures the length a plastic will stretch to the point of breaking and is commonly displayed in percentage.

The longer the stretch distance, the greater the value and thus the more elastomeric the material. This elastomeric characteristic of the material has a usefulness in the selection of products for test socket applications.

Test data suggests that the lower the Tensile Elongation at Yield value, the more precise the placement of the hole. The thought is that on a microscopic level, the drill bit “dances” a bit more on the softer more forgiving surface before penetrating the plastic. This slight shift can lead to slightly off target hole placement.

The data below suggests a material with 10% Tensile Elongation is far less accurate in placement than a hole at 3%. 

So many factors to consider when selecting the optimum material for your Test Socket or Micro Machined application. Feel free to contact Port Plastics for suggestions on materials, whether static controlled ESd products or non static controlled, we have the largest selection of Semiconductor materials on the globe.