Impact of Cooling Rate during High-Pressure Gas Quenching on Fatigue Performance of Low Pressure Carburized GearsShow others and affiliations
2022 (English)In: Metals, ISSN 2075-4701, Vol. 12, no 11, article id 1917Article in journal (Refereed) Published
Abstract [en]
The impact of cooling rate during high-pressure gas quenching on the fatigue performance of low-pressure carburized spur gears was studied for steel grades 20MnCr5 and 17NiCrMo6-4. The results show an increased fatigue limit by 10 to 11% when applying a slower cooling rate for both steel grades. Moreover, for 20MnCr5 the slower cooled gears show an increase in compressive residual stresses by 130 MPa compared to the faster cooling, although no significant difference was observed for 17NiCrMo6-4. It is also seen that the cooling rate affects the core hardness for both steel grades, while other properties like surface hardness, case-hardness depth and martensite variant pairing were unaffected. The results for the retained austenite content and average martensite unit size show no clear effect of the cooling rate. The possible influence of different carbon distributions after quenching for the two used cooling rates on the carbide precipitation and fatigue limit is discussed. © 2022 by the authors.
Place, publisher, year, edition, pages
MDPI , 2022. Vol. 12, no 11, article id 1917
Keywords [en]
case-hardened gears, fatigue, high-pressure gas quenching, low pressure carburizing, Martensite transformation
National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:ri:diva-61200DOI: 10.3390/met12111917Scopus ID: 2-s2.0-85141694705OAI: oai:DiVA.org:ri-61200DiVA, id: diva2:1716699
Note
Funding details: Fellowships Fund Incorporated, FFI; Funding text 1: This work was supported by the Vinnova project “Controlled quenching at case hardening for optimal performance—QuenchCool” within the programme “Strategic Vehicle Research and Innovation” (FFI) of which this research was part of.
2022-12-062022-12-062023-05-08Bibliographically approved