Increasing demands on quality and stability in production processes also impose greater demands on heat treatment in industry. The furnace or heat treatment equipment must be manufactured in such a way as to reproducibly meet demanding specific requirements, eg the prescribed charge temperature. These requirements are defined by CQI-9 (for the automotive industry) and AMS 2750 E (for the aerospace and defense industries). Requirements for thermal processing equipment are eg:
Furnaces or ovens meeting the heat treatment accreditation process in the National Aerospace and Defense Accreditation Program (NADCAP) shall be so manufactured as to reproducibly meet the requirements of AMS 2750 E:
The customer determines according to heat treatment requirements:
The special heat treatment process CQI-9 is an evaluation of the heat treatment system and must be carried out at least once a year. This standard is an annex to ISO TS 16949 according to the “customer-specific requirements” and is valid for all automotive suppliers worldwide who have concluded a quality contract in the automotive supply chain.