High Performance Sinter Hardening Materials for Synchronizing Hubs
The development of synchronizing hubs goes towards more complicated shapes and higher performance, at the same time as there is a strong pressure on costs. Today many high performance synchronizing hubs are produced using different diffusion bonded materials like Distaloy AE and Distaloy HP. With the new demands it is a desire to move to materials and processes with better cost/performance ratio. This means to move away from high and unstable costs for pure nickel and molybdenum to pre-alloyed materials preferable based on chromium with none or smaller additions of plain nickel. Astaloy CrA and Astaloy LH are pre-alloyed powders suitable for sinter hardening. By selecting different additions of copper or nickel as well as the carbon content the properties can be tailored for different strength requirements. The usage of CCT-diagrams can assist in the selection of the optimal composition depending on which cooling rate that can be applied.