Influence of Tempering and Cryogenic Treatment on Retained Austenite and Residual Stresses in Carbonitrided 18CrNiMo7-6 Low Alloy Steel

Simple item page
dc.contributor.authorKatemi, J. Richard
dc.contributor.authorEpp, Jeremy
dc.date.accessioned2020-06-15T11:03:41Z
dc.date.available2020-06-15T11:03:41Z
dc.date.issued2019-06
dc.description.abstractThis work investigated the influence of tempering conditions coupled with cryogenic treatment on thermal stabilization of retained austenite and residual stress distributions in carbonitrided 18CrNiMo76 low alloy steel samples. The carbonitriding conditions were set to enable attaining surface carbon and nitrogen content of 0.87 and 0.34 mass.-percent respectively. After carbonitriding, some of the samples were subjected to varying tempering conditions followed by cryogenic treatment at -120 °C using nitrogen gas. Analysis of both retained austenite and residual stresses was conducted using X-ray diffraction. In the as-quenched state, carbonitrided samples contained 52 mass.-percent. Samples that were directly subjected to the cryogenic treatment after quenching retained only about 20 mass.-percent of austenite. Samples subjected to variant tempering conditions coupled with cryogenic treatment retained at least 30 masses.-percent of austenite. A thermal stabilization of retained austenite which increases with increasing temperature was identified. On tempering at 240°C for 14 hours retained austenite becomes unstable and decomposes to bainite leading to the low initial amount of retained austenite before cryogenic treatment. It can be concluded that the tempering process coupled with cryogenic treatment leads to an increasing hardness, to higher compressive residual stresses as well as to a shift of the location of maximum compressive residual stress toward the surface.en_US
dc.identifier.citationTanz. J. Engrg. Technolen_US
dc.identifier.issn1821-536X
dc.identifier.urihttp://hdl.handle.net/20.500.11810/5465
dc.language.isoenen_US
dc.publisherTanzania Journal of Engineering and Technologyen_US
dc.relation.ispartofseriesVol. 38;1
dc.subjectCarbonitriding, cryogenic, residual stress, tempering, XRDen_US
dc.titleInfluence of Tempering and Cryogenic Treatment on Retained Austenite and Residual Stresses in Carbonitrided 18CrNiMo7-6 Low Alloy Steelen_US
dc.typeJournal Articleen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Influence of Tempering and Cryogenic Treatment on retained Austenite and Residual Stresses in Carbonitrided 18CrNiMo7-6 Low Alloy Steel.pdf
Size:
3.92 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Department of Chemical and Mining Engineeering