Betriebsfeste Bemessung von Bauteilen aus Sinterstahl und ihre Sicherheit. Tl.2

The design of fatigue loaded parts requires on the one hand the knowledge about material related data, like fatigue life curves for constant and variable amplitude loading in dependence on notch factor, mean stress, loading mode as well as the scatter due to material and manufacturing processes, on the other hand the knowledge about service loading and its scatter as well as about geometry and resulting local stresses in highly stressed areas. Only the comparison of acting and allowable stresses will allow the conclusion, whether the part will fulfill a required fatigue life or whether further design and material modifications will be necessary. After a presentation of material related and design relevant data and parameters for different sintered steels it is discussed how to selcet material, sintering technology (single or double sintering), surface heat treatment for the examples of two different P/M'parts on the basis of data obtained from specimens. Finally a reliability and safet y analysis is presented, which is based upon the possible scatters mentioned above