Fabrication
The assembly is composed of six PM parts including a bushing-tensioner retainer and an index coupler. The former, a six-level component, required two-upper and three-lower punches for compaction on a CNC servo-controlled press. The index coupler has nine holes formed during compaction, and 29 different identifying letters and numbers for functional operation in the assembly. Tapping the holes was the only machining operation. All six parts are made from FC-0208-50 with a yield strength of 380 MPa, ultimate tensile strength of 410 MPa, and tensile rupture strength of 860 MPa. This material offered a superior combination of properties in the as-sintered (non-heat treated) condition, since some of the components required machining for tolerance or shape requirements.