Case Study: PM Rack

Process: Conventional powder metallurgy
Yield Strength: 43,000 psi minimum
Tensile Strength: 55,000 tsi
Hardness: 65 HRB

End Use and Function

This powder metallurgy (PM) component is a complex seven-level rack used in an industrial washing machine. The rack, along with the mating gear, is what agitates the drum in the washing machine.

PM Rack
2012 Award of Distinction : PM Rack

Fabrication

Made to a density of 6.8 g/cm³, the component has sectional density that is kept equal within 0.08 g/cm³. The part has a minimum yield strength of 43,000 psi and typical 55,000 psi tensile strength. The process control required a high level of tool geometry control along with minimum weight and sectional density variation at compact and a consistent sinter temperature profile.

Results

Originally a die cast part that needed extensive machining, the conversation of this part to powder metallurgy resulted in:

  • A 38% cost reduction
  • Enhanced precision