Sinter-hardening studies distaloy DH powders with varying carbon contents

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2013
Kılıç, Gülten
In this study, the effect of sinter-hardening on the mechanical properties of Distaloy DH (Fe-2Cu-1.5Mo) powder with 0.4%, 0.6%, and 0,8% graphite additions, was investigated. Powder samples were pressed under 600 MPa, and sintered at 1120°C under endogas from methane for 20 minutes in an industrial sintering furnace. After sintering the samples were cooled with three different cooling rates (0.5°C/sec,1.5°C/sec, and 3°C/sec). Microstructural characterization of samples were done with optical and electron microscopy. Selective etching was utilized in determining the amount of pearlite in samples. The study showed that after sintering, a cooling rate of 0.5°C/s led to decreasing amounts of pearlite in all the Distaloy DH samples with increasing amount of carbon. With increase in the cooling rates to 3°C/s, Distaloy DH-0.4%C sample containis small amount of pearlite, whereas the alloys Distaloy DH–0.6%C and Distaloy DH-0.8%C led to bainitc and martensitic microstructures.

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Citation Formats
G. Kılıç, “Sinter-hardening studies distaloy DH powders with varying carbon contents,” M.S. - Master of Science, Middle East Technical University, 2013.