Variable valve timing (VVT) systems have done much to improve fuel efficiency and to reduce emission levels of combustion engines. These factors are of increasing importance with stricter legislation and higher demands upon sustainable transportation. Components for VVT require a complex shape and make high demands on dimensional precision and machinability. Their complex
geometry makes VVT components very suitable applications for PM. In addition, commercial manufacturing of VVT parts require high productivity and a minimized scrap rate.

This paper describes a new powder mix concept that has been developed to meet the requirements of efficient manufacturing, and a trial of stator components under full production conditions validates the concept. Factors influencing the production efficiency and product precision such as die filling, compaction, and machinability have been investigated. Results from the tests show that this new concept enables improvement of dimensional precision and productivity, thus improving overall manufacturing effectiveness.