The deformation rate sensitivities of additively and conventionally fabricated 316L alloys için kapak resmi
The deformation rate sensitivities of additively and conventionally fabricated 316L alloys
Başlık:
The deformation rate sensitivities of additively and conventionally fabricated 316L alloys
Yazar:
Enser, Samed, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
x, 82 leaves: charts;+ 1 computer laser optical disc.
Özet:
The compression stress-strain behavior of a Scanning Laser Melt 316L (SLM-316L) and an annealed and extruded commercial 316L (C-316L) were determined between 1x10-3 s-1 and 2500-3150 s-1. SLM-316L deformed by twinning and slip, while C-316L by martensitic transformation and slip with no fracture until about 0.51 strain. The higher yield strength of SLM-316L than C-316L was attributed to the higher dislocation density of SLM-316L. The higher work hardening rate of C-316L alloy was proved due to the higher resistance of martensite plate than twin boundary to the dislocation motion. As the strain rate increased, both alloys showed increased flow stresses. However, the rate sensitivities declined as the strain increased due to the adiabatic heating at high strain rates. The Johnson and Cook flow stress material models of both alloys were further determined for the adiabatic and isothermal conditions. The martensite formation in C-316L specimens and twinning formation in SLM-316L alloys decreased at high strain rates compared to quasi-static strain rates. The XRD spectra of C-316L also confirmed the reduced martensite formation at high strain rates. The reduced twin and martensite formation at high strain rates were attributed to the increased stacking fault energy due to the adiabatic heating of the test specimens. The increase of stacking fault energy at high strain rates promoted a higher fraction of the deformation by slip. Lastly, the reloading tests revealed a strain-rate history effect in SLM-316L and no strain-rate history effect in C-316L.
Konu Başlığı:
Yazar Ek Girişi:
Tek Biçim Eser Adı:
Thesis (Master)--İzmir Institute of Technology: Mechanical Engineering.

İzmir Institute of Technology: Mechanical Engineering--Thesis (Master).
Elektronik Erişim:
Access to Electronic Versiyon.
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