Fabrication
The sinter-hardened steel rack and five-level pinion and the copper steel bushing are pressed to net shape with one cross-drilled hole being the only secondary operation performed. The assembly was designed to be sinter bonded for strength. The parts have a typical density of 6.7 g/cm³, 75,000 psi ultimate tensile strength, 135,000 psi transverse rupture strength, and 20 HRC min. apparent hardness and 52 HRC min. particle hardness.
Results
Because of the large number of assemblies required in each louver system, the PM process gave the customer the only cost-effective option, delivering an estimated 75% savings over the machined alternative.