Certification sent with a lot after processing, listing the specification, furnace, recipe, temperatures, times, quenchant, hardness results and case depth where required, signed by quality. Aerospace and automotive customers will not accept parts without one, and a missing or wrong cert can hold up a whole shipment. Certs also means the mill test reports that arrive with raw steel.
Parts are on the truck but the cert is still sitting on the QA desk, nobody signed it.
A cert should report what was actually measured. Auditors flag certs where every hardness reading lands on the same number.
Also heard as
- certs
- heat treat cert
- C of C
- cert of conformance
Related terms
Traveler
The paperwork that rides with a lot through the shop, recording each operation, furnace, time and result.
TUS
Temperature uniformity survey: a test mapping how evenly a furnace holds temperature across its work zone.
Pyrometry
The practice of measuring and controlling furnace temperature: sensors, instruments, calibration and surveys.
Rockwell hardness
The standard shop hardness test that presses a diamond or ball into a part and reads depth as a number.