Investigation of the effect of vacuum cementation on sinterability and mechanical properties of Fe-based composite materials produced by powder metallurgy method

Abstract

In this study; Fe-based composite materials with 100% Fe and 0.2-0.4% graphite content were produced by powder metallurgy (P/M) method. The samples produced were subjected to only sintering, sintering + vacuum cementation + tempering and only vacuum cementation + tempering processes. Three point bending test and microhardness measurements were performed to determine the mechanical properties of the samples. Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDS) were used to examine the microstructure and three-point bending fracture surfaces of the samples. As a result of the examinations, it was observed that the neck formation between the powder grains and the sintering process occurred in the samples that were only subjected to vacuum cementation. In this way, the hardening and sintering processes of Fe-based composite materials by vacuum cementation method can be done together. Thus, it will be possible to increase the usage areas of composite materials produced by the P/M method, to reduce production costs, to reduce the consumption of natural resources and to protect the ecosystem.