In:
Metallurgical and Materials Transactions A, Springer Science and Business Media LLC, Vol. 52, No. 10 ( 2021-10), p. 4331-4341
Abstract:
In this study, the influence of cold rotary swaging on microstructure and mechanical properties of the precipitation-strengthened nickel-based superalloy 718 (Alloy 718) was investigated. The initial stages of work-hardening were characterized by means of microhardness, electron backscatter diffraction (EBSD), and X-ray diffraction (XRD) analyses. Furthermore, attention was devoted to the mechanical behavior at ambient and elevated temperature (550 °C) in uniaxial tension and compression. Rotary swaging to different true strains of maximum $$\varphi = 0.91$$ φ = 0.91 caused a moderate increase of microhardness and enhanced markedly the load-bearing capacity in tension, giving rise to yield strength beyond 2000 MPa. The mechanical strength $$R_{p0.2}$$ R p 0.2 in tension subsequent to rotary swaging perfectly correlates with increasing dislocation density $$\rho $$ ρ estimated from XRD in the form of a Taylor-like relationship $$R_{p0.2} \propto \sqrt{\rho }$$ R p 0.2 ∝ ρ . In compression, transient stress–strain evolution without the occurrence of a clear elastic range and distinct yield phenomenon was observed. Restoration of the elastic range, accompanied by a pronounced increase of microhardness, was obtained by a post-swaging tempering treatment at 600 °C.
Type of Medium:
Online Resource
ISSN:
1073-5623
,
1543-1940
DOI:
10.1007/s11661-021-06371-w
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2021
detail.hit.zdb_id:
1179415-X
detail.hit.zdb_id:
2037517-7
detail.hit.zdb_id:
192156-3
SSG:
19,1
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