Abstract
The effects of carbon potential in vacuum-carburization on the surface-hardened layer properties of the 0.2%C-1.5%Si-1.5%Mn-1.0%Cr-0.05%Nb transformation-induced plasticity-aided martensitic steel were investigated for the fabrication of precision gears. The volume fraction of retained austenite and hardness in the surface hardened layer of the steel increased with increasing carbon potential. Subsequent fine-particle peening enhanced the hardness and the compressive residual stress via severe plastic deformation and strain-induced martensite transformation, especially under a high carbon potential. The severe plastic deformation mainly contributed to increased hardness and compressive residual stress and the contribution of the strain-induced martensitic transformation was relatively small.
Highlights
Sugimoto et al [10,11] reported that fine-particle peening (FPP) further increases the rotational bending and torsional fatigue strengths of heat-treated TRIP-aided martensitic (TM) steel by imparting a significant hardness and compressive residual stress to the precision-gear surface layer
There have only been a few reports on the microstructure and the fatigue strength of carburized TM steel subjected to FPP [19,20]
The main results can be summarized as follows: (1) Vacuum‐carburization resulted in a large amount of retained austenite and high Vickers hardness in the surface hardened layer of the steel with a low residual stress from 0 MPa to 60
Summary
Sugimoto et al [10,11] reported that fine-particle peening (FPP) further increases the rotational bending and torsional fatigue strengths of heat-treated TM steel by imparting a significant hardness and compressive residual stress to the precision-gear surface layer. Numerous researchers have reported that high-energy shot peening increases the fatigue strength of these steels [12,13]. Higher fatigue strengths of TM steel may be achieved by gas- or vacuum-carburizing with shot peening and/or. There have only been a few reports on the microstructure and the fatigue strength of carburized TM steel subjected to FPP [19,20]. No investigation has been conducted into the effects of vacuum-carburization conditions on the surface-hardened layer properties of TM steel
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
