Fatigue behaviour of screwed sintered materials with different strength and heat treatment

For the design of screwed components, information about static pull-out and fatigue behaviour are required. The appropriate data and manufacturing methods for various PM-steels and PM-aluminium alloys were determined and compared with existing results for cast and wrought materials. The pull-out behaviour is defined by the critical screwing depth. The screwing depth necessary for adequate fatigue behaviour is defined by using metallography. In comparison to cast iron and wrought steels the fatigue strength of PM-materials is higher because of a better stress distribution in the thread due to the higher resilience related to the porosity.