Material testing is an important component of our quality control system. Our customers expect that the parts we ship them meet not only the dimensional requirements but the physical requirements as well. Design Engineers rely on us to meet minimum mechanical properties so the parts they have developed perform as intended. If the parts don’t meet expectations, serious failures can & will occur.
For Profile Precision Extrusions, material testing starts prior to the delivery of our raw material. Our raw material specifications call out specific alloying elements. Each aluminum alloy we produce has its own specific chemical recipe. Our suppliers certify and report to us the actual chemistry of each order they deliver to us. When we ship an order to our customer, we report, on our Material Certification, the actual chemistry of the aluminum we used to produce the order. This is typically required by our medical & aviation customers. Below is an example of how we report the actual chemistry:
When we are planning to produce an order, we need to consider the temperature of the raw material going into the extrusion press; the temperature of the aluminum exiting the extrusion press; (the aluminum heats up during extrusion due to pressure and friction); and how quickly we need to cool the extrusion down after it has exited the extrusion press. After the extrusion has been cooled and stretched, one last thermal process, called artificial aging, gives the extrusions their final temper.
After artificial aging we are ready to perform our own in-house mechanical testing. Our testing procedure involves preparing a sample, placing the sample into our Instron electromechanical testing system, and pulling the sample until it breaks into two pieces. The system measures yield strength, tensile strength and elongation. The specifications we manufacture each order to specify the minimum acceptable result. Below is an example of how we report our results:
Occasionally an order does not meet the minimum requirements. When we have a failure, we perform a 2nd test to make sure the sample we tested was properly prepared. Despite our pre-production planning, mistakes are occasionally made. If the 2nd test fails, we scrap all of the extrusions and re-run the order. Our customers expect no less from us, and we hold ourselves to that same standard.
