Authors:
Maheswaran Vattur Sundaram (1), Fredrik Vinnerborg (1)
1- Höganäs AB, Sweden
Abstract:
Astaloy® CrS is a Cr pre-alloyed water-atomised powder containing 0.85wt.%Cr and 0.15wt.%Mo, developed as a sustainable alternative to Fe-Cu-C PM steels. For applications demanding higher performance, secondary operations such as heat treatments(HT) are necessary. Carburising is one HT process to improve surface hardness, wear resistance, and fatigue strength, leading to superior performance. For Fe-Cu-C materials, gas carburising(GC) is conventionally used, but for Cr pre-alloyed materials, low-pressure carburising(LPC) is preferred since it prevents oxidation. This investigation assesses the processing capabilities and the material requirements for successful heat treatment of CrS. To achieve this, LPC and GC were performed on both CrS and Fe-Cu-C samples with densities ranging from 7.1 to 7.4 g/cm3, sintered at 1120°C. The results indicated a higher static and fatigue performance after GC for CrS than the Fe-Cu-C. LPC provides better control of case depth for varying densities but requires a material with better hardenability for gas quenching.
DOI:
https://doi.org/10.59499/EP246278537
