Under the industry's rigid standards for lightweighting, high durability, and low noise in automotive seats, stainless steel and aluminum alloy hardware — as core components of seat slide rails, recliners, and seat frame connectors — depend heavily on how well material selection matches the processing technology; this directly determines the dimensional tolerance stability, fatigue life, and mass-production cost of the parts. Based on the IATF16949 Quality Management System Standard for Automotive Parts, this article systematically outlines a refined process selection scheme for seat hardware, providing a reference for automotive parts buyers, seat system integrators, and auto parts supply chain sourcing decisions.