Interpretation of Profile and Intercept Counts in Microstructure Characterization

The results of intercept and profile counts are commonly interpreted as a suitable estimates of the mean grain size as represented e.g. by the grain density V. The term grain size is not explicitly defined even when some relation to grain volume and/or mean grain breadth (the mean Ferret diameter) is tacitly assumed. However, the intercept count L is directly related to the mean value of grain boundary area per unit volume SV and the profile count A is, under relatively general assumptions, directly related to the mean value of grain junctions per unit volume LV. Their relation to V can be generally written as V = c¢(A)3/2 = c²(L)3, but the coefficients c¢ and c² strongly depend on the structural characteristics like grain size dispersion, anisotropy etc. and their evaluation is far from being simple. Consequently, whereas the reliable estimates of SV and LV result from intercept and profile counts, the estimate of grain density based on them requires a careful consideration.

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Effect of Grain Size Distribution on Second Order Stresses in Plastically Deformed Polycrystals

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.505 ◽

2006 ◽

Vol 524-525 ◽

pp. 505-510

Author(s):

Stephane Berbenni ◽

Marcel Berveiller

Keyword(s):

Grain Size ◽

Size Distribution ◽

Yield Stress ◽

Internal Structure ◽

Grain Size Distribution ◽

Second Order ◽

Local Flow ◽

Mean Grain Size ◽

The Mean ◽

Size Dispersion

The overall behaviour of metals composed of grains with different sizes is simulated as well as the evolution of their internal structure making use a self-consistent modelling for elasticviscoplastic materials. The Representative Volume Element is composed of isotropic spherical grains randomly distributed with a grain size distribution following a log-normal statistical function. Thus the heterogeneity of the RVE comes only from the grain size dependence of the local flow stress. The viscoplastic strain rate of the grains is modelled through a classic isotropic power law involving a reference stress depending on the individual grain size and the local plastic strain. Numerical results applied to IF steels firstly display that the overall yield stress depends not only on the mean grain size but also on the dispersion of the grain diameter distribution. The role of the grain size dispersion becomes significant when the mean grain size is on the order of "m, and, a decrease of the overall yield stress with an increase of the dispersion is observed. Secondly, prediction of the evolution of the internal structure indicates an increase of second order internal stresses with grain size dispersion. When this one is large enough and the mean grain size is on the order of "m, residual stresses due to heterogeneities arising from the grain size distribution are on the same order than the ones related to heterogeneities associated with plastic anisotropy found for polycrystalline IF steels.

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Preparation of high-entropy carbides by different sintering techniques

Journal of Materials Science ◽

10.1007/s10853-021-06004-y ◽

2021 ◽

Vol 56 (19) ◽

pp. 11237-11247 ◽

Cited By ~ 1

Author(s):

Johannes Pötschke ◽

Manisha Dahal ◽

Mathias Herrmann ◽

Anne Vornberger ◽

Björn Matthey ◽

...

Keyword(s):

Grain Size ◽

Single Phase ◽

X Ray Diffraction ◽

Vacuum Sintering ◽

X Ray ◽

High Entropy ◽

Mean Grain Size ◽

The Mean ◽

Gas Pressure Sintering ◽

Hardness Values

AbstractDense (Hf, Ta, Nb, Ti, V)C- and (Ta, Nb, Ti, V, W)C-based high-entropy carbides (HEC) were produced by three different sintering techniques: gas pressure sintering/sinter–HIP at 1900 °C and 100 bar Ar, vacuum sintering at 2250 °C and 0.001 bar as well as SPS/FAST at 2000 °C and 60 MPa pressure. The relative density varied from 97.9 to 100%, with SPS producing 100% dense samples with both compositions. Grain size measurements showed that the substitution of Hf with W leads to an increase in the mean grain size of 5–10 times the size of the (Hf, Ta, Nb, Ti, V,)C samples. Vacuum-sintered samples showed uniform grain size distribution regardless of composition. EDS mapping revealed the formation of a solid solution with no intermetallic phases or element clustering. X-ray diffraction analysis showed the structure of mostly single-phase cubic high-entropy carbides. Hardness measurements revealed that (Hf, Ta, Nb, Ti, V)C samples possess higher hardness values than (Ta, Nb, Ti, V, W)C samples.

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The possibility of rapid testing of the mean grain size of rolled metal

Russian Journal of Nondestructive Testing ◽

10.1134/s1061830908010051 ◽

2008 ◽

Vol 44 (1) ◽

pp. 41-44 ◽

Cited By ~ 2

Author(s):

A. V. Kurkov

Keyword(s):

Grain Size ◽

Rapid Testing ◽

Rolled Metal ◽

Mean Grain Size ◽

The Mean

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EFFECT OF GRAIN SIZE ON THE ELECTRON WORK FUNCTION OF Cu AND Al

Surface Review and Letters ◽

10.1142/s0218625x04006025 ◽

2004 ◽

Vol 11 (02) ◽

pp. 173-178 ◽

Cited By ~ 17

Author(s):

WEN LI ◽

D. Y. LI

Keyword(s):

Grain Size ◽

Phase Transformation ◽

Grain Boundary ◽

Work Function ◽

Electron Work Function ◽

Deformation Texture ◽

Kelvin Probe ◽

Surface Conditions ◽

The Mean ◽

Sophisticated Instrument

The Kelvin probe is a sophisticated instrument which is very sensitive to changes in surface conditions, such as deformation, texture, phase transformation and contamination. Efforts have been made to use this technique to diagnose wear. In this study, the effect of the grain boundary (GB) on the electron work function (EWF) was examined with the aim of investigating the contribution of changes in grain size to total changes in the EWF during wear. Copper and aluminum were studied as examples. It was demonstrated that the EWF dropped in the vicinity of GB's and the mean EWF decreased as the grain size decreased. The mechanism responsible for the changes in the EWF with respect to the GB is discussed.

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Fabrication of (SiC-AlN)/ZrB2 Composite with Nano-Micron Hybrid Microstructure via PCS-Derived Ceramics Route

Materials ◽

10.3390/ma14020334 ◽

2021 ◽

Vol 14 (2) ◽

pp. 334

Author(s):

Aidong Xia ◽

Jie Yin ◽

Xiao Chen ◽

Zhengren Huang ◽

Xuejian Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Flexural Strength ◽

Hot Pressing ◽

Raw Materials ◽

Secondary Phase ◽

Pressing Temperature ◽

Xrd Pattern ◽

Mean Grain Size ◽

The Mean

In this work, a (SiC-AlN)/ZrB2 composite with outstanding mechanical properties was prepared by using polymer-derived ceramics (PDCs) and hot-pressing technique. Flexural strength reached up to 460 ± 41 MPa, while AlN and ZrB2 contents were 10 wt%, and 15 wt%, respectively, under a hot-pressing temperature of 2000 °C. XRD pattern-evidenced SiC generated by pyrolysis of polycarbosilane (PCS) was mainly composed by 2H-SiC and 4H-SiC, both belonging to α-SiC. Micron-level ZrB2 secondary phase was observed inside the (SiC-AlN)/ZrB2 composite, while the mean grain size (MGS) of SiC-AlN matrix was approximately 97 nm. This unique nano-micron hybrid microstructure enhanced the mechanical properties. The present investigation provided a feasible tactic for strengthening ceramics from PDCs raw materials.

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The Study on the Fabrication of Nano-Structured Steel by Cold Rolling and Annealing of Martensite

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1807 ◽

2013 ◽

Vol 634-638 ◽

pp. 1807-1810

Author(s):

Guang Xu ◽

Jing Yang ◽

Tao Xiong ◽

Peng Deng ◽

Long Fei Cao

Keyword(s):

Grain Size ◽

Cold Rolling ◽

High Strength ◽

Total Elongation ◽

Plain Carbon Steel ◽

Mean Grain Size ◽

Cold Rolling And Annealing ◽

The Mean ◽

Martensite Microstructure ◽

Very High

Sub-nano structured steel was obtained by cold rolling and annealing martensite microstructure for a plain carbon steel. The mean grain size is several hundreds nanometer. The steel has very high strength and also good total elongation.

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Paleolimnology of Lake Yamanaka as reflected on particle-size distribution

Bulletin of the Department of Geology ◽

10.3126/bdg.v14i0.5437 ◽

1970 ◽

Vol 14 ◽

pp. 35-42 ◽

Cited By ~ 1

Author(s):

Danda Pani Adhikari

Keyword(s):

Particle Size ◽

Grain Size ◽

Size Distribution ◽

Central Japan ◽

Size Frequency Distribution ◽

Factors Affecting ◽

Mean Grain Size ◽

The Mean ◽

Main Factors ◽

Lake Size

A 17.63 m long bore-hole core extracted from the deepest part of Lake Yamanaka, one of the Fuji-five Lakes at the northeasternfoot of Mount Fuji, central Japan, composed of sediment with intercalations of scoria fallout deposits. The sediment of the upper11.4 m was investigated for grain-size distribution by using a laser diffraction particle size analyser. The mean grain-size profileshowed various degrees of fluctuations, both short-and long-terms, and the size-frequency distribution revealed unimodal-trimodalmixing of sediments. Changes in lake size and water depth appear to be the main factors affecting the variability in the grain-sizedistribution and properties. The lake level appears low during 7000–5000 cal BP and 2800–1150 cal BP and relatively high during5000–2800 cal BP and 1150 cal BP– present.DOI: http://dx.doi.org/10.3126/bdg.v14i0.5437Bulletin of the Department of Geology Vol.14 2011, pp.35-42

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Modern quantitative microstructure analysis on the example of aicu5mg1 alloys

Acta periodica technologica ◽

10.2298/apt0233109b ◽

2002 ◽

pp. 109-114

Author(s):

Biljana Zlaticanin ◽

Branislav Radonjic ◽

Branka Jordovic

Keyword(s):

Grain Size ◽

Chemical Composition ◽

Linear Method ◽

Titanium Content ◽

Mean Value ◽

Grain Refining ◽

Relative Standard ◽

Method Of Measurement ◽

The Mean ◽

Picture Analysis

Using an automatic, QUANTIMET 500 MC, device for quantitative picture analysis and applying linear method of measurement on the example of AlCu5Mg1 alloys, the grain size (min, max and medium values), as well as relative standard measuring errors (RSE), dendrite arm spacing (DAS) and length eutectic (Le) and also distribution by size (histogram) and volume participation of ?-hard solution and eutectic have been determined. We have also studied the influence of grain-refining additives AlTi5B1 for the same chemical composition of the aluminium-capper-magnesium alloy. It has been concluded that with the increase of titanium content, the mean value of grain size decreases. We have also examined hardness and pressure strength.

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Microstructure and Mechanical Performance of AZ31-1.7 Wt.% Si Alloy Processed by Cyclic Channel Die Compression

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.457 ◽

2010 ◽

Vol 667-669 ◽

pp. 457-461

Author(s):

Wei Guo ◽

Qu Dong Wang ◽

Man Ping Liu ◽

Tao Peng ◽

Xin Tao Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Mechanical Performance ◽

Chinese Script ◽

Cast State ◽

Microstructure And Mechanical Properties ◽

Mean Grain Size ◽

The Matrix ◽

The Mean

Cyclic channel die compression (CCDC) of AZ31-1.7 wt.% Si alloy was performed up to 5 passes at 623 K in order to investigate the microstructure and mechanical properties of compressed alloys. The results show that multi-pass CCDC is very effective to refine the matrix grain and Mg2Si phases. After the alloy is processed for 5 passes, the mean grain size decreases from 300 μm of as-cast to 8 μm. Both dendritic and Chinese script type Mg2Si phases break into small polygonal pieces and distribute uniformly in the matrix. The tensile strength increases prominently from 118 MPa to 216 MPa, whereas the hardness of alloy deformed 5 passes only increase by 8.4% compared with as-cast state.

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