The majority of fatigue data generated from PM laboratory test specimens have utilized the traditional stress-based approach. This approach is based on nominal (average) stresses within a component that is being analyzed. While most engineered components are designed such that nominal stresses remain elastic during service loads, local areas of stress concentration can cause plastic strains. The strain-based approach to fatigue involves detailed analysis of localized plastic deformation (yielding) that may occur in areas of stress concentration and is used as a basis for calculating fatigue life.
A long-term fatigue program is being conducted by CPMT in collaboration with the Metal Powder Industries Federation (MPIF) Standards Committee to determine the strain-based fatigue properties of sintered materials. To date, reports have included ferrous alloys FC-0205,
FC-0208, FN-0200, FN-0205, FL-4405, FL-5305, FLN2-4400, FLN2-4405, FLN2-4408,
FLNC-4408, FLC-4208, FLC-4608 and PM aluminum alloy AC-2014.