Entwicklung mit Hilfe des Warmpreßverfahrens hergestellter Sinterstähle mit optimaler Warmstreckgrenze,Dauerfestigkeit und Kerbschlagzähigkeit – Teil 1

Development of Hot-Forged Sintered Steels with Optimum Yield Point at Higher Temperature, Fatigue and Impact Strength . The material characteristic values of hot-forged sintered steels are reported. Besides the usual properties, (ultimate tensile strength, yield strength and elongation at room temperature). The behaviour of materials at higher temperature is of great importance. Further, fatigue strength and impact strength must be considered. The influence of heat treatment on these properties were investigated and brought to a correlation with the formation of microstructures. The hot forging P/M preform requires a special attention on alloying elements and alloying techniques. Optimum properties results when using completely alloyed powders or mixed powders by employing special master alloys. This and further problems involving alloying techniques and particularly the behaviour of carbon as an alloying element is reported in details. The correlation between mechanical properties and fracture behaviour is discussed.