Sinter-hardening studies distaloy DH powders with varying carbon contents

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.


Sinter hardening studies of ASTALOY 85 Mo powder with varying copper contents /
Dinçer, Mehmet; Ögel, Bilgehan; Durlu, Nuri; Department of Metallurgical and Materials Engineering (2014)
In this thesis study, the effect of sinter hardening on mechanical properties of Astaloy 85 Mo (Fe - 0.85% Mo) powder with addition of 0.8% C and varying copper contents (1% Cu, 2% Cu) was examined. Powder mixes were compacted under 600 MPa. After compaction, the samples were sintered at 1120oC under endogas from methane in an industrial sintering furnace and were sinter-hardened with three different cooling rates (0.5oC/sec., 1.5oC/sec., 3oC/sec.). The study revealed that the cooling rate does not make cri...
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Çevik, Gül; Doruk, Mustafa; Department of Metallurgical and Materials Engineering (2004)
In the present work, the effect of variation in specimen orientation and heat treatment on the Stress Corrosion Cracking (SCC) susceptibility of 7050 aluminum alloy was investigated in 3,5% NaCl solution and under freely corroding conditions. For this purpose, Constant Extension Rate Tests (CERT) was performed on precracked Compact Tension (CT) specimens and the Direct Current Potential Drop technique was applied to measure the crack lengths. In addition to crack length versus time curves, the relationship ...
Microstructural and elecrochemical characterization of Ti-6A1-4V ELI alloy
Topçuoğlu, Melih; Aydınol, Mehmet Kadri; Department of Metallurgical and Materials Engineering (2006)
In this study, the evolution of structure and the relationship between microstructure and corrosion behavior of the Ti-6Al-4V ELI (Extra Low Interstitial) alloy was investigated in Ringer’s solution at 37 ± 0.1 oC. Initially, different heat treatments were performed in order to obtain several microstructures which were; Widmanstätten α for furnace cooling (FC), basket-weave α for air cooling (AC), martensite (α') for water quenching (WQ) from 1060 oC, and aged martensite for ten hours at 500, 600, 700, 800,...
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Esen, Ziya; Bor, Şakir; Department of Metallurgical and Materials Engineering (2007)
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Processing and characterization of high density tungsten-nickel-iron alloys
Çalışkan, Necmettin Kaan; Bor, Şakir; Durlu, Nuri; Department of Metallurgical and Materials Engineering (2013)
In the present study, processing of W-Ni-Fe alloys by liquid phase sintering technique has been investigated. Effect of sintering atmospheres (hydrogen and vacuum), tungsten content altering from 90 to 97 wt.%, Ni/Fe ratio varied from 2 to 4 and post sintering treatments (heat treatment and swaging) on the microstructure and mechanical properties of W-Ni-Fe alloys have been analyzed. Liquid phase sintered alloys were characterized by mechanical tests, electron microscopy and XRD studies, thermal analyses an...
Citation Formats
G. Kılıç, “Sinter-hardening studies distaloy DH powders with varying carbon contents,” M.S. - Master of Science, Middle East Technical University, 2013.