Mechanical characterization by traction and small punch tests of ultra-fine grained AISI 316L with bimodal grain size distributions

2019 ◽  
Author(s):  
C. Keller ◽  
B. Flipon ◽  
M. Diez ◽  
M. Serrano
Keyword(s):  
Grain Size ◽  
Mechanical Characterization ◽  
Size Distributions ◽  
Aisi 316L ◽  
Small Punch ◽  
Fine Grained ◽  
Grain Size Distributions ◽  
Bimodal Grain Size

scholarly journals Three-Dimensional in situ Reconstructions of Microstructures with Bimodal Grain Size Distributions

2019 ◽  
Vol 25 (S2) ◽  
pp. 370-371
Author(s):  
Ashley Bucsek ◽  
Lee Casalena ◽  
Darren C. Pagan ◽  
Partha P. Paul ◽  
Yuriy Chumlyakov ◽  
...  
Keyword(s):  
Grain Size ◽  
Three Dimensional ◽  
Size Distributions ◽  
Grain Size Distributions ◽  
Bimodal Grain Size

Changes in Grain Size Distribution of a Submicron Grained Al-Sc Alloy during High Temperature Annealing

2006 ◽  
Vol 519-521 ◽  
pp. 1617-1622 ◽  
Author(s):  
N. Burhan ◽  
Michael Ferry
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Elevated Temperatures ◽  
Large Fraction ◽  
Direct Consequence ◽  
Size Distributions ◽  
Grain Coarsening ◽  
Fine Grained ◽  
Grain Size Distributions

Severe plastic straining is an established method for producing submicron grain (SMG) structures in alloys. However, the development of such a fine grained structure in single-phase alloys is usually futile if they are to be exposed or processed at elevated temperatures. This is a direct consequence of the natural tendency for rapid and substantial grain coarsening which completely removes the benefits obtained by grain refinement. This problem may be avoided by the introduction of nanosized, highly stable particles in the metal matrix. In this work, a SMG structure was generated in an Al-0.3 wt.% Sc alloy by Equal Channel Angular Pressing (ECAP). The alloy was prepared initially to produce a fine grained microstructure exhibiting a large fraction of high angle grain boundaries and a dispersion of nanosized Al3Sc particles. The evolution of microstructure during annealing at temperatures up to 550 °C was examined in detail and grain size distributions generated from the data. It was shown that grain coarsening is rapid at temperatures above 450 °C and the initial log-normal grain size distribution exhibiting low variance and skewness was altered considerably. The statistical information generated from the grain size distributions confirms that discontinuous grain coarsening occurs in this alloy only at temperatures greater than 500 °C.

scholarly journals Grain Growth after Intercritical Rolling

2004 ◽  
Vol 467-470 ◽  
pp. 305-310 ◽  
Author(s):  
Roumen H. Petrov ◽  
Leo Kestens ◽  
Kim Verbeken ◽  
Yvan Houbaert
Keyword(s):  
Grain Size ◽  
Size Distributions ◽  
Orientation Microscopy ◽  
Final Rolling Temperature ◽  
Responsible Mechanism ◽  
Grain Size Distributions ◽  
Intercritical Region ◽  
Final Rolling ◽  
Parent Austenite ◽  
Bimodal Grain Size

The distribution of the characteristic texture components between the ferrite grains of different size classes has been studied in a steel with 0.082%C, 1.54% Mn, 0.35% Si, 0.055%Nb and 0.078%V after different rolling schedules with a final rolling temperature above or below Ar3. Microstructures and textures were characterized by means of optical microscopy and orientation microscopy. A strong grain refining effect together with a bimodal grain size distribution was observed in the steel both after final rolling in the intercritical region or in the austenite region, close to the Ar3 d temperature. The differences in grain size were interpreted on the basis of three potentially acting mechanisms: (i) transformation- induced recrystallization, (ii) increased mobility of specific grain boundaries and (iii) fast nucleation of ferrite grains on specific sites of the parent austenite microstructure. The experimental data clearly favoured the third of these assumptions as the responsible mechanism for the observed bimodal grain size distributions.

scholarly journals Failure Mechanisms of Alloys with a Bimodal Graine Size Distribution

2020 ◽  
pp. 521-534
Author(s):  
Vladimir A. Skripnyak ◽  
Evgeniya G. Skripnyak ◽  
Vladimir V. Skripnyak
Keyword(s):  
Grain Size ◽  
Titanium Alloys ◽  
Size Distribution ◽  
Dynamic Loading ◽  
Grain Size Distribution ◽  
High Strain ◽  
Fine Grained ◽  
Localization Of Plastic Deformation ◽  
Grain Size Distributions ◽  
Bimodal Grain Size

AbstractA multi-scale computational approach was used for the investigation of a high strain rate deformation and fracture of magnesium and titanium alloys with a bimodal distribution of grain sizes under dynamic loading. The processes of inelastic deformation and damage of titanium alloys were investigated at the mesoscale level by the numerical simulation method. It was shown that localization of plastic deformation under tension at high strain rates depends on grain size distribution. The critical fracture stress of alloys depends on relative volumes of coarse grains in representative volume. Microcracks nucleation at quasi-static and dynamic loading is associated with strain localization in ultra-fine grained partial volumes. Microcracks arise in the vicinity of coarse and ultrafine grains boundaries. It is revealed that the occurrence of a bimodal grain size distributions causes increased ductility, but decreased tensile strength of UFG alloys. The increase in fine precipitation concentration results not only strengthening but also an increase in ductility of UFG alloys with bimodal grain size distribution.

Sign in / Sign up

Export Citation Format

Share Document