Using the Hollomon Model to Predict Strain-Hardening in Metals
Raymond Kwesi Nutor,
Nana Kwabena Adomako,
Y. Z. Fang
Issue:
Volume 2, Issue 1, January 2017
Pages:
1-4
Received:
12 March 2017
Accepted:
5 April 2017
Published:
19 April 2017
Abstract: Stress – strain values obtained from tensile tests of aluminium and steel is used to evaluate the true stress – true strain values. The Hollomon’s model is then used to predict the strain-hardening behavior in the two specimens. It is clearly seen that the strain-hardening behavior in metals can be described using the Hollomon’s model. However, we have assumed that the onset of strain-hardening is at the yield point up until the ultimate tensile strength. The correlation between the experimental true stress – true strain values of aluminium and the calculated values using the Hollomon equation is much better than that of steel.
Abstract: Stress – strain values obtained from tensile tests of aluminium and steel is used to evaluate the true stress – true strain values. The Hollomon’s model is then used to predict the strain-hardening behavior in the two specimens. It is clearly seen that the strain-hardening behavior in metals can be described using the Hollomon’s model. However, we ...
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Advanced Synthesis and 3D-AFM-Structural Features of Mono-Metalized Cyclotetraphosphates
Khaled M. Elsabawy,
A. El-Maghraby
Issue:
Volume 2, Issue 1, January 2017
Pages:
5-16
Received:
12 March 2017
Accepted:
29 March 2017
Published:
19 April 2017
Abstract: Solution route applying the precursor of metaldihydrogen phosphate dihydrate was used to synthesize M-cyclophosphatesat ambient temperature (cobalt (II) was selected as model for metal in these investigations). The precursor was fired and sintered at different temperatures (600, 800, 1000 and 1100°C) respectively to optimize best conditions to obtain Co2P4O12 crystal form with high purity. The products were monitored by both of XRD, IR spectra by additional to accurate imaging via scanning electron microscope (SEM) and AFM-microscopeto analyzesurface topology and microstructural features of the metal cyclotetraphosphate. Structural investigations via XRD proved that the product obtained at 1100°C is the best and fine structure with monoclinic structure phase and C12/C1 space group with lattice parameter a=11.809(2), b=8.293(1), c=9.923(2) A respectively. A visualized investigations were performed to confirm structure validity and stability at temperature of sintering (1100°C). Visualization studies indicated that variations of bond distances between Co1, Co2, P1 and P2 and different six oxygen atoms (O1, O2, O3, O4, O5 and O6) inside crystal lattice are responsible for increasing lattice flexibility factor (by controlling in shrinkage and expansion coefficient) and consequently increase its bonds stability to break.
Abstract: Solution route applying the precursor of metaldihydrogen phosphate dihydrate was used to synthesize M-cyclophosphatesat ambient temperature (cobalt (II) was selected as model for metal in these investigations). The precursor was fired and sintered at different temperatures (600, 800, 1000 and 1100°C) respectively to optimize best conditions to obta...
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