Test method for availability of holes in height - temperature barrier on cementation process

In design and production of many electrical sensors barriers, which separate contact system and sensitive element are used. These barriers are of different materials depending on operation environment and functionality. In automotive high temperature sensors the main material is cement which does not allow humidity and ensure protection of contact system. A test method for hardness of high temperature barrier made by cement is developed. The test principle is: certain air volume is supplied in a work chamber with initial pressure level where the analyzed part is located. Then the latest pressure level is measured. Constant-time is calculated out of various points of transitional process. Based on the results a coefficient ensuring barrier without defects is calculated. For repeatability of measurement results SPC (statistical process control) and MSA (measurement system analyze) methods are used. The test guaranties stable cementing process and zero defects at the customer.