scholarly journals Formability of the 5754-Aluminum Alloy Deformed by a Modified Repetitive Corrugation and Straightening Process

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 633 ◽  
Author(s):  
Marco Ezequiel ◽  
Sergio Elizalde ◽  
José-María Cabrera ◽  
Josep Picas ◽  
Ignacio A. Figueroa ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Microstructural Analysis ◽  
Rate Sensitivity ◽  
Tensile Tests ◽  
Orientation Distribution ◽  
Sensitivity Coefficient ◽  
Mechanical Tests ◽  
Forming Limit

Sheets of 5754-aluminum alloy processed by a modified repetitive corrugation and straightening (RCS) process were tested in order to measure their formability. For this purpose, forming limit curves were derived. They showed that the material forming capacity decreased after being processed by RCS. However, they kept good formability in the initial stages of the RCS process. The formability study was complemented with microstructural analysis (derivation of texture) and mechanical tests to obtain the strain-rate sensitivity. The texture analysis was done by employing X-ray diffraction, obtaining pole figures, and the orientation distribution function. It was noticed that the initial texture was conserved after successive RCS passes, but the intensity dropped. RCS process did not induce β-fiber, contrary to common deformation process. The strain-rate sensitivity coefficient was measured through tensile tests at different temperatures and strain rates; the coefficient of the samples processed after one and two passes were still relatively high, indicating the capacity to delay necking, in agreement with the good formability observed in the initial passes of the RCS process.

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

2012 ◽  
Vol 57 (4) ◽  
pp. 1253-1259 ◽  
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.

A Study on Rate Sensitivity of Impedance in TRIP Steel during Deformation at Various Strain Rate under Two Kinds of Deformation Mode

2014 ◽  
Vol 566 ◽  
pp. 140-145
Author(s):  
Daiki Inoshita ◽  
Takeshi Iwamoto
Keyword(s):  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Trip Steel ◽  
Testing Machine ◽  
Rate Sensitivity ◽  
Deformation Mode ◽  
Tensile Tests ◽  
Material Testing ◽  
Trip Steels ◽  
Material Testing Machine

TRIP steel possesses excellent mechanical properties dominated by strain-induced martensitic transformation (SIMT). For automotive industries, if TRIP steel can be applied to shock absorption members, it can be considered that the weight of automobile can be reduced. However, the strain rate sensitivity of TRIP steels has not been fully understood because the strain rate sensitivity and the deformation mode dependency of SIMT are still unclear. Therefore, it is important to reveal these sensitivity and dependency for confirming a reliability of TRIP steel. Therefore, in this study, it is attempted to estimate the amount of produced martensite in TRIP steel by measuring the inductance of TRIP steel. The specimen made of TRIP steel is used as a core of a prototype coil manufactured in this study. Then, the compressive and tensile tests are conducted by using a material testing machine and a drop weight testing machine using the specimen inside the coil. The inductance of the coil with the deformed specimen are measured continuously during the tests.

The effect of minor element concentrations on the strain rate sensitivity and ductility of commercial purity aluminium sheet

1980 ◽  
Vol 295 (1413) ◽  
pp. 130-130
Keyword(s):  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Rate Sensitivity ◽  
Minor Element ◽  
Tensile Tests ◽  
Plastic Instability ◽  
Alloy Sheet ◽  
Second Phase ◽  
Commercial Purity ◽  
Aluminium Sheet

Minor element levels vary considerably in commercial purity ( ca .99.5 % Al) aluminium alloy sheet obtained from various sources. Minor elements may be present in solution or as second phase particles formed during solidification or subsequent processing. The present work is largely concerned with the effects of elements in solution on strain-rate sensitivity and ductility. Recent treatments of plastic instability in tensile tests incorporate the strain rate sensitivity and note its importance in determining the strain at which instability occurs (Ghosh 1977; Marciniak 1974). Tensile properties have been determined on a range of aluminium sheet samples. The results show that small increases in solute concentration can result in a change from positive (flow stress increasing with strain rate) to negative strain rate sensitivity. The rate sensitivity was found to be strain dependent and this had led to a reconsideration of the effect of strain rate sensitivity on ductility. The work suggests that it is not the absolute value of the rate sensitivity that determines its effect on the strain to plastic instability, but rather the sign of its variation with strain. If this is positive then the strain to instability exceeds that expected in the absence of rate sensitivity; if the slope is negative the opposite trend is observed.

High Strain Rate Compressive Behaviour of Selective Laser Melted Ti-6Al-4V

2017 ◽  
Vol 890 ◽  
pp. 323-326 ◽  
Author(s):  
Maziar Ramezani ◽  
Emmanuel Flores-Johnson ◽  
Lu Ming Shen ◽  
Thomas Neitzert
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Shear Failure ◽  
High Strain ◽  
Split Hopkinson Pressure Bar ◽  
Rate Sensitivity ◽  
Melting Process ◽  
Mechanical Tests ◽  
Hopkinson Pressure Bar

Ti-6Al-4V alloy is one of the most important engineering alloys, combining attractive properties with inherent workability. The aim of this study is to investigate the effect of strain rate on the compressive mechanical properties of Ti6Al4V alloy manufactured by a selective laser melting process. The mechanical tests were performed by means of a compression split Hopkinson pressure bar apparatus under high strain rate ranging from 1400 s-1 to 4500 s-1. The true stress-strain curves obtained from static and dynamic compressive tests show strain rate sensitivity from quasi-static (peak strength 1300MPa) to high strain rate (peak 1500 MPa). Within the high strain rate range tested, the strain rate sensitivity is not remarkable. The fractographic analysis shows a relatively smooth and smeared fractured surface along with a dimple like structure. The observation of elongated dimples confirms the operation of a dynamic shear failure mechanism for the additively manufactured Ti-6Al-4V parts.

Superplasticity of an AA2519 Aluminum Alloy

2016 ◽  
Vol 838-839 ◽  
pp. 278-284
Author(s):  
Ivan Zuiko ◽  
Marat Gazizov ◽  
Rustam Kaibyshev
Keyword(s):  
Strain Rate ◽  
Thermomechanical Processing ◽  
Rate Sensitivity ◽  
Initial Strain Rate ◽  
Tensile Tests ◽  
Sensitivity Coefficient ◽  
Initial Strain ◽  
Strain Rates ◽  
Average Grain Size ◽  
Elongation To Failure

A commercial AA2519 alloy with a chemical composition of Al-5.64Cu-0.33Mn-0.23Mg-0.15Zr (in wt. %) was subjected to two-step thermomechanical processing (TMP) providing the formation of fully recrystallized structure with an average grain size of ~7 mm in 3 mm thin sheets. Superplastic tensile tests were performed in the temperature interval 450-535°C and initial strain rates ranging from ~2.8 x 10-4 to ~6.0 x 10-1 s-1. The highest elongation-to-failure of ~750% appears at a temperature of ~525°C and an initial strain rate of ~1.4 × 10-4 s-1 with the corresponding strain rate sensitivity coefficient of ~0.46.

Hot Deformation Behaviour of Low Alloyed Steel

2012 ◽  
Vol 706-709 ◽  
pp. 2794-2799 ◽  
Author(s):  
Cecilia Poletti ◽  
S. Großeiber ◽  
Sergiu Ilie ◽  
Hans Peter Degischer
Keyword(s):  
Strain Rate ◽  
Strain Rate Sensitivity ◽  
Hot Deformation ◽  
Power Efficiency ◽  
Deformation Behaviour ◽  
Rate Sensitivity ◽  
Tensile Tests ◽  
Alloyed Steel ◽  
Strain Rates ◽  
Low Alloyed Steel

Hot deformation of a continuously cast low alloyed steel is studied by means of hot compression and tensile tests carried out after austenitization between 700–790 °C at 3x10-4– 0.3 s-1of strain rate. The ferrite transformation at the applied cooling rate was determined at 710°C by means of dilatometry. The compressive flow data obtained by using a Gleeble®1500 machine are evaluated to obtain the strain rate sensitivity and the processing maps using different models. The tensile data are used to determine the ductility of the material with different deformation parameters. A new calculation method is used for the instability parameter derived from the dynamic materials model. The strain rate sensitivity does not predict any instability but all the others instability parameters do, including the new one. Pores are formed at the prior austenitic grain boundaries at low strain rates, causing a decay of ductility in the tensile samples. A minimum in the ductility was observed for low strain rates at 750°C. Low strain rates and low temperatures increase the formation of more ferrite than without deformation at the corresponding heat treatments without deformation. In these conditions, the deformation is concentrated in the softer ferrite phase. Low power efficiency was calculated at high strain rates, where no dynamic recrystallization takes place. The domains with similar efficiency of power dissipation are correlated to deformation induced ferrite formation and ferrite recovery. These domains vary with the increasing strain.

Sign in / Sign up

Export Citation Format

Share Document