Constitutive Model Over Wide Temperature Range and Considering Negative-to-Positive Strain Rate Sensitivity for As-Quenched AA2219 Sheet

ABSTRACTThe compressive ductilities of Ni3Al-Zr-B base alloys with sole addition of magnesium (0.02∼0.06wt.%) and combined addition of magnesium(0.02wt.%) and silicon(0.54∼1.08wt.%) respectively responding to strain rate rising from 10-4sec-1 to 10-1 sec-1 have been studied in a high temperature range of 1073∼1273K. The results show that the compressive strains at rupture(CSR) of the alloys have been greatly improved by sole addition of magnesium and the alloys with combined addition of magnesium and silicon reveal even higher CSR values, furthermore, at temperatures of 1073K and 1273K, the strain rate dependence of CSR reveals to be anomalous, i.e, the CSR value increases as the strain rate rises, and then declines until it surpasses the peak value, which is corresponded to the strain rate of 10-3 sec-1 and 10-3 sec-1 respectively.The beneficial effect of magnesium and silicon exists in their competence of reducing strain rate sensitivity exponent values. The mechanisms of the anomalous ductilizing behavior in the Ni3Al as affected by ternary elements are discussed.

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Microstructure and Plasticity of Hot Deformed 5083 Aluminum Alloy Produced by Rapid Solidification and Hot Extrusion / Badania Mikrostruktury I Plastyczności Odkształcanego Na Gorąco Szybko-Krystalizowanego I Wyciskanego Stopu Aluminium 5083

Archives of Metallurgy and Materials ◽

10.2478/v10172-012-0140-2 ◽

2012 ◽

Vol 57 (4) ◽

pp. 1253-1259 ◽

Cited By ~ 8

Author(s):

T. Tokarski ◽

Ł. Wzorek ◽

H. Dybiec

Keyword(s):

Aluminum Alloy ◽

High Temperature ◽

Flow Stress ◽

Strain Rate ◽

Strain Rate Sensitivity ◽

Rate Sensitivity ◽

Temperature Range ◽

Rapidly Solidified ◽

5083 Aluminum Alloy ◽

Conventionally Cast

The objective of the present study is to analyze the mechanical properties and thermal stability for rapidly solidified and extruded 5083 aluminum alloy (RS). Compression tests were performed in order to estimate flow stress and strain rate sensitivity relation for 5083 alloy in the temperature range of 20°C to 450°C. For the comparison purposes, conventionally cast and extruded industrial material (IM) was studied as well. Deformation tests performed at room temperature conditions show that rapidly solidified material exhibits about 40% higher yield stress (YS=320 MPa) than conventionally cast material (YS=180 MPa), while the deformation at 450°C results in significant decrease of flow stress parameters for RS material (YS=20 MPa) in comparison to IM material (YS=40 MPa). Strain rate sensitivity parameter determined for high temperature conditions indicates superplasticity behavior of RS material. Structural observations show that under conditions of high-temperature deformation there are no operating recrystallization mechanisms. In general, grain size below 1µm and size of reinforcing phases below 50 nm is preserved within the used deformation temperature range.

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Negative to positive strain rate sensitivity in 5xxx series aluminum alloys: Experiment and constitutive modeling

International Journal of Plasticity ◽

10.1016/j.ijplas.2013.11.001 ◽

2014 ◽

Vol 55 ◽

pp. 232-246 ◽

Cited By ~ 70

Author(s):

Farhoud Kabirian ◽

Akhtar S. Khan ◽

Amit Pandey

Keyword(s):

Aluminum Alloys ◽

Strain Rate ◽

Strain Rate Sensitivity ◽

Constitutive Modeling ◽

Rate Sensitivity ◽

Positive Strain

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On the Effect of Strain Rate and Temperature on the Yield Strength Anomaly in L21-structured Fe2AlMn

MRS Proceedings ◽

10.1557/proc-1128-u05-09 ◽

2008 ◽

Vol 1128 ◽

Author(s):

Markus W. Wittmann ◽

Janelle M. Chang ◽

Yifeng Liao ◽

Ian Baker

Keyword(s):

Yield Strength ◽

Strain Rate ◽

Single Crystals ◽

Yield Stress ◽

Strain Rate Sensitivity ◽

Rate Sensitivity ◽

Temperature Range ◽

Effects Of Temperature ◽

Increasing Temperature

AbstractThe effects of strain rate and temperature on the yield strength of near-stoichiometric Fe2AlMn single crystals were investigated. In the temperature range 600-800K the yield stress increased with increasing temperature, a response commonly referred to as a yield strength anomaly. No strain rate sensitivity was observed below 750K, but at higher temperatures the yield stress increased with increasing strain rate. Possible mechanisms to explaining the effects of temperature and strain rate are discussed.

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