Instrumentation and Control of a Bulge Test on a Superplastic Pb-Sn Alloy

Superplasticity is characterized by high elongations under a high strain rate sensibility, and it’s variation with strain rate, temperature and grain size. This parameter is often obtained from uniaxial tensile test. However, superplastic deformation is a biaxial process; hence there is a need to develop a way to get this parameter in a biaxial test. This work aims to set up the instrumentation to record and control a biaxial superplastic forming in a Pb-Sn alloy. The control system project has been divided into tracking variables: strain and pressure. The instrumentation is able to predict the breaking point at the beginning of the superplastic forming process from biaxial testing.

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New Strategy for the Prediction of the Gas Pressure Profile of Superplastic Forming of Al-5083 Aluminium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.735.204 ◽

2012 ◽

Vol 735 ◽

pp. 204-209 ◽

Cited By ~ 1

Author(s):

Nagore Otegi ◽

Lander Galdos ◽

Iñaki Hurtado ◽

Sean B. Leen

Keyword(s):

Strain Rate ◽

Constant Strain Rate ◽

Superplastic Forming ◽

Pressure Profile ◽

Bulge Test ◽

Forming Process ◽

Optimum Pressure ◽

New Approach ◽

Superplastic Alloy ◽

New Strategy

This paper describes a new approach for identification of the optimum pressure history for SPF processes, based on mechanisms-based hyperbolic constitutive equations. This equation set has been modified to incorporate the effect of the damage behaviour the material suffers due to the cavitational evolution of Al-5083 superplastic alloy. A large deformation, multiaxial formulation of the constitutive equation set is implemented and applied to finite element modelling of a bulge test forming process to characterise the cavitation evolution behaviour in the bulge test, using conventional (constant strain rate) and the newly proposed (variable strain rate) strategy.

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Investigation of Anisotropy Effect on the Material Properties Obtained from Biaxial Tests

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.856.128 ◽

2020 ◽

Vol 856 ◽

pp. 128-134

Author(s):

Chalida Udomraksasakul ◽

Thanasan Intarakumthornchai ◽

Yingyot Aue-u-Lan

Keyword(s):

Flow Stress ◽

Tensile Test ◽

Mechanical Test ◽

Rolling Direction ◽

Uniaxial Tensile ◽

Bulge Test ◽

Uniaxial Tensile Test ◽

Biaxial Test ◽

Anisotropy Effect ◽

Biaxial Tests

Hydraulic bulge test or biaxial test is a well-known mechanical test used to determine a flow stress of material because of the large level of effective strains and not interfered by the necking unlike in uniaxial tensile test. However, the flow stress obtained is influenced by the anisotropy effect. That flow stress needs to be corrected by the anisotropic values (r-values) obtained from the uniaxial tensile test which limited by the necking. Therefore, to obtain the accurate flow stress the r-values should be determined directly from the biaxial test. The elliptical tests with ratio of 2 (the ratio between major and minor axis) at different sheet orientations (0๐ and 90๐ from the rolling direction) and the equibiaxial test were proposed. In this research, the effect of the sheet orientations upon the flow stress (K and n values) under biaxial tests was investigated by experiment and equation of material grade SPCD with the thickness of 0.8mm. The results showed that the flow stress without correcting r-values gave more variations than those with correcting one with the r-values obtained from the uniaxial test. Therefore, the r-values used to correct the flow stress under biaxial test should be directly determined from the biaxial test.

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Coupled Thermomechanical Response Measurement of Deformation of Nickel-Based Superalloys Using Full-Field Digital Image Correlation and Infrared Thermography

Materials ◽

10.3390/ma14092163 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2163

Author(s):

Krzysztof Żaba ◽

Tomasz Trzepieciński ◽

Sandra Puchlerska ◽

Piotr Noga ◽

Maciej Balcerzak

Keyword(s):

Surface Temperature ◽

Strain Rate ◽

Rolling Direction ◽

Image Correlation ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Response Measurement ◽

Sheet Rolling ◽

Inconel Alloys ◽

The Relationship

The paper is devoted to highlighting the potential application of the quantitative imaging technique through results associated with work hardening, strain rate and heat generated during elastic and plastic deformation. The aim of the research presented in this article is to determine the relationship between deformation in the uniaxial tensile test of samples made of 1-mm-thick nickel-based superalloys and their change in temperature during deformation. The relationship between yield stress and the Taylor–Quinney coefficient and their change with the strain rate were determined. The research material was 1-mm-thick sheets of three grades of Inconel alloys: 625 HX and 718. The Aramis (GOM GmbH, a company of the ZEISS Group) measurement system and high-sensitivity infrared thermal imaging camera were used for the tests. The uniaxial tensile tests were carried out at three different strain rates. A clear tendency to increase the sample temperature with an increase in the strain rate was observed. This conclusion applies to all materials and directions of sample cutting investigated with respect to the sheet-rolling direction. An almost linear correlation was found between the percent strain and the value of the maximum surface temperature of the specimens. The method used is helpful in assessing the extent of homogeneity of the strain and the material effort during its deformation based on the measurement of the surface temperature.

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Viscoplastic Constitutive Model for High Strain Rate Mechanical Properties of SAC-Q Leadfree Solder After High-Temperature Prolonged Storage

ASME 2018 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2018-8357 ◽

2018 ◽

Cited By ~ 3

Author(s):

Pradeep Lall ◽

Vikas Yadav ◽

Jeff Suhling ◽

David Locker

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

High Strain Rate ◽

Strain Rate ◽

Thermal Aging ◽

High Strain ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Aging Effects ◽

Model Predictions

Electronics in automotive underhood and downhole drilling applications may be subjected to sustained operation at high temperature in addition to high strain-rate loads. SAC solders used for second level interconnects have been shown to experience degradation in high strain-rate mechanical properties under sustained exposure to high temperatures. Industry search for solutions for resisting the high-temperature degradation of SAC solders has focused on the addition of dopants to the alloy. In this study, a doped SAC solder called SAC-Q solder have been studied. The high strain rate mechanical properties of SAC-Q solder have been studied under elevated temperatures up to 200°C. Samples with thermal aging at 50°C for up to 6-months have been used for measurements in uniaxial tensile tests. Measurements for SAC-Q have been compared to SAC105 and SAC305 for identical test conditions and sample geometry. Data from the SAC-Q measurements has been fit to the Anand Viscoplasticity model. In order to assess the predictive power of the model, the computed Anand parameters have been used to simulate the uniaxial tensile test and the model predictions compared with experimental data. Model predictions show good correlation with experimental measurements. The presented approach extends the Anand Model to include thermal aging effects.

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Performance evaluation of HDPE/MWCNT and HDPE/kenaf composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705719868278 ◽

2019 ◽

pp. 089270571986827 ◽

Cited By ~ 3

Author(s):

Nayan Pundhir ◽

Sunny Zafar ◽

Himanshu Pathak

Keyword(s):

Tensile Test ◽

Strain Rate ◽

Polymer Composite ◽

Tensile Modulus ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Compression Moulding ◽

Multi Walled Carbon Nanotube ◽

Kenaf Composites ◽

The Impact

The present work deals with the microwave-assisted compression moulding of high-density polyethylene (HDPE)-based composites. In the present work, 20 wt% of reinforcement in the form of kenaf and multi-walled carbon nanotube (MWCNT) was used to fabricate HDPE/kenaf and HDPE/MWCNT polymer composites. The mechanical characterizations of the microwave-processed composites were carried out in terms of uniaxial tensile test with different strain rate, multistep stress relaxation, flexural and impact test. The uniaxial tensile test revealed that the tensile modulus of microwave-processed four-layered HDPE/kenaf polymer composite was 35.2% higher than that of HDPE/MWCNT polymer composite. The HDPE/MWCNT polymer composite showed a minimum of 1.25 GPa and a maximum of 4.7 GPa of elastic modulus when tested at different strain rate. The impact energy absorbed by the HDPE/kenaf polymer composite (1.055 J) was 81.12% higher than the HDPE/MWCNT polymer composite (0.582 J).

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Determination of Flow Curve Using Bulge Test and Calibration of Damage for Ito-Goya Models

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.182 ◽

2013 ◽

Vol 554-557 ◽

pp. 182-189 ◽

Cited By ~ 4

Author(s):

Bruno Martins ◽

Abel D. Santos ◽

Pedro Teixeira ◽

K. Ito ◽

N. Mori

Keyword(s):

Tensile Test ◽

Damage Model ◽

Strain Curve ◽

Uniaxial Tensile ◽

Bulge Test ◽

Uniaxial Tensile Test ◽

Damage Prediction ◽

Damage Models ◽

Material Information

The standard uniaxial tensile test is the widely accepted method to obtain relevant properties of mechanical characterization of sheet metal materials. However the range of strain obtained from tensile test is limited. The bulge test is an alternative to obtain ranges of deformation, higher than tensile test, thus permitting a better characterization for material behaviour. This paper presents a sensitivity analysis for some influencing variables used in bulge measurements, thus giving some guidelines for the evaluation of the stress-strain curve from experimental results using a developed experimental mechanical system. Additionally, using bulge test up to fracture shall give material information regarding damage, which in turn may be used to evaluate and calibrate damage models. A methodology is presented to be used for evaluation and calibration of Ito-Goya damage model of damage prediction.

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An Experimental Study on Elevated Temperature Biaxial Bulge Test

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.430-432.539 ◽

2012 ◽

Vol 430-432 ◽

pp. 539-542 ◽

Cited By ~ 2

Author(s):

Ho Sung Lee ◽

Jong Hoon Yoon ◽

Joon Tae Yoo

Keyword(s):

Elevated Temperature ◽

Strain Rate ◽

Rate Sensitivity ◽

Metal Sheet ◽

Bulge Test ◽

Nickel Base Superalloy ◽

Test Results ◽

Forming Process ◽

Uniaxial Test ◽

Nickel Base

By using biaxial bulge test, it is possible to predict sheet metal forming behavior during hot forming process. The purpose of this study is to obtain materials parameters for elevated temperature forming condition during biaxial bulge test of a nickel base superalloy in hemispherical die. At constant gas pressure, the strain rate in which the metal sheet experiences varies and therefore the strain rate sensitivity can be obtained in a single loading. Biaxial bulge tests on superalloy metal sheet were performed and results are in satisfactory agreement with uniaxial test results at elevated temperature.

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Further Investigation of the Hydrostatic Bulge Test in a Plasticity Laboratory

International Journal of Mechanical Engineering Education ◽

10.7227/ijmee.37.2.7 ◽

2009 ◽

Vol 37 (2) ◽

pp. 159-174

Author(s):

O. Ifedi ◽

Q. M. Li ◽

Y. B. Lu

Keyword(s):

Tensile Test ◽

Effective Stress ◽

Strain Curve ◽

Plasticity Theory ◽

Loading Path ◽

Uniaxial Tensile ◽

Bulge Test ◽

Uniaxial Tensile Test ◽

Stress Strain Curve ◽

Stress Strain

In plasticity theory, the effective stress–strain curve of a metal is independent of the loading path. The simplest loading path to obtain the effective stress–strain curve is a uniaxial tensile test. In order to demonstrate in a plasticity laboratory that the stress–strain curve is independent of the loading path, the hydrostatic bulge test has been used to provide a balanced biaxial tensile stress state. In our plasticity laboratory we compared several different theories for the hydrostatic bulge test for the determination of the effective stress–strain curve for two representative metals, brass and aluminium alloy. Finite element analysis (FEA) was performed based on the uniaxial tension test data. It was shown that the effective stress–strain curve obtained from the biaxial tensile test (hydrostatic bulge test) had a good correlation with that obtained in the uniaxial tensile test and agreed well with the analytical and FEA results. This paper may be used to support an experimental and numerical laboratory in teaching the concepts of effective stress and strain in plasticity theory.

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