scholarly journals Inverse Identification for the Balanced Biaxial Yield Stress of AA5182-O Alloy Sheet

2021 ◽  
Author(s):  
Yong Zhang ◽  
Qing Zhang ◽  
Yuantao Sun ◽  
Dateng Zheng
Keyword(s):  
Yield Stress ◽  
Shell Element ◽  
Alloy Sheet ◽  
Bulge Test ◽  
Inverse Identification ◽  
Punch Force ◽  
Elastic Boundary ◽  
Hydraulic Bulge ◽  
Yield Functions ◽  
The Relationship

Abstract Advanced yield functions, such as Yld2004, could describe the elastic boundary of materials better than the traditional. However the balanced biaxial yield stress σb which is essential to determine the parameters of advanced yield functions is hard to measure using frequently used test equipment. This work presented an inverse method to calibrate σb of AA5182-O alloy sheet based on the Erichsen test. The maximum punch force (MPF) measured from this test was used for the inverse identification. A modification coefficient was used to drop down the simulation MPF from shell element, as the application of shell element result in higher simulation punch force. Then the relationship between σb and MPF was established based on the plane stress Yld2004. With this relationship and the real measured MPF, σb could be inversely identified. Additionally, a hydraulic bulge test was performed to verify the accuracy of this inversely obtained σb.

Biaxial Work Hardening Characteristics of 6000 Series Aluminum Alloy Sheet for Large Strain Range

2012 ◽  
Author(s):  
Daisaku Yanaga ◽  
Toshihiko Kuwabara ◽  
Naoyuki Uema ◽  
Mineo Asano
Keyword(s):  
Aluminum Alloy ◽  
Plastic Strain ◽  
Work Hardening ◽  
Deformation Behavior ◽  
Alloy Sheet ◽  
Bulge Test ◽  
Aluminum Alloy Sheet ◽  
Stress Space ◽  
Plastic Deformation Behavior ◽  
Yield Functions

Deformation behavior of 0.9-mm-thick 6016-T4 aluminum alloy sheet with a high intensity of the cube orientation under biaxial tension was investigated. First, many linear stress paths in the first quadrant of stress space were applied to cruciform specimens to precisely measure the deformation behavior of the test material up to an equivalent strain of 0.04. True stress-true plastic strain curves, contours of plastic work in stress space and the directions of plastic strain rates were measured and compared with those calculated using selected yield functions. Second, in an effort to observe the plastic deformation behavior of the sample up to much larger strains over 0.1, the sample was bent and YAG-laser welded to fabricate tubular specimens with an inner diameter of 44.6mm. Using a servo-controlled tension-internal pressure testing machine, plane strain tension tests were performed. Hydraulic bulge test was also performed. The material exhibits significant differential work hardening; the Yld2000-2d yield functions with exponents of 6, 12 and 32 had the best agreement with the experimental work contours for the equivalent plastic strains of 0.002, 0.04 and 0.14, respectively.

Estimation of Fracture Toughness JIC by Miniature Specimen Hydraulic Bulge Test

2017 ◽  
Vol 898 ◽  
pp. 753-757
Author(s):  
Le Le Gui ◽  
Tong Xu ◽  
Bin An Shou ◽  
Han Kui Wang ◽  
Jing Xiang
Keyword(s):  
Fracture Toughness ◽  
Fracture Energy ◽  
Fracture Strain ◽  
Bulge Test ◽  
Miniature Specimen ◽  
Hydraulic Bulge Test ◽  
Hydraulic Bulge ◽  
Resistance Curves ◽  
Miniature Specimens ◽  
Load Deflection Curve

The fracture toughness tests and a new miniature specimen technology named hydraulic bulge test (HBT) of 3Cr1Mo1/4V at four service time were carried out. Four J-R resistance curves by single-specimen method with one inch CT specimens were obtained to compute the JIC. Different definitions of equivalent fracture strain according to the section morphologies of HBT testing specimens were compared, and fracture energy of miniature specimens with three different thicknesses (0.4mm, 0.5mm and 0.6mm) were also calculated. Results showed that the typical HBT load-deflection curve can be divided into four sections like SPT curve. Equivalent fracture strain and fracture energy EHB can be chosen as two fracture parameters for the HBT specimen. Ductile fracture toughness JIC can be related approximately linearly to both the equivalent fracture strain and fracture energy EHB.

scholarly journals Comparison of the Effects of Conching Parameters on the Contents of Three Dominant Flavan3-ols, Rheological Properties and Sensory Quality in Chocolate Milk Mass Based on Liquor from Unroasted Cocoa Beans

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2502
Author(s):  
Bogumiła Urbańska ◽  
Hanna Kowalska ◽  
Karolina Szulc ◽  
Małgorzata Ziarno ◽  
Irina Pochitskaya ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Yield Stress ◽  
Sensory Quality ◽  
Raw Material ◽  
Antioxidant Compounds ◽  
Chocolate Milk ◽  
Cocoa Beans ◽  
Variable Parameters ◽  
The Relationship ◽  
Manufacturing Parameters

The content of polyphenols in chocolate depends on many factors related to the properties of raw material and manufacturing parameters. The trend toward developing chocolates made from unroasted cocoa beans encourages research in this area. In addition, modern customers attach great importance to how the food they consume benefits their bodies. One such benefit that consumers value is the preservation of natural antioxidant compounds in food products (e.g., polyphenols). Therefore, in our study we attempted to determine the relationship between variable parameters at the conching stage (i.e., temperature and time of) and the content of dominant polyphenols (i.e.,catechins, epicatechins, and procyanidin B2) in chocolate milk mass (CMM) obtained from unroasted cocoa beans. Increasing the conching temperature from 50 to 60 °C decreased the content of three basic flavan-3-ols. The highest number of these compounds was determined when the process was carried out at 50 °C. However, the time that caused the least degradation of these compounds differed. For catechin, it was 2 h; for epicatechin it was 1 h; and for procyanidin it was 3 h. The influence of both the temperature and conching time on the rheological properties of chocolate milk mass was demonstrated. At 50 °C, the viscosity and the yield stress of the conched mass showed its highest value.

Hydraulic Bulge Test of Electrodeposited Copper Foil

1999 ◽  
Vol 77 (2) ◽  
pp. 55-59 ◽  
Author(s):  
H. D. Merchant ◽  
M. G. Rozboril
Keyword(s):  
Copper Foil ◽  
Bulge Test ◽  
Hydraulic Bulge Test ◽  
Hydraulic Bulge

A Comparative Study on Hydraulic Bulge Testing and Analysis Methods

2008 ◽  
Author(s):  
Eren Billur ◽  
Muammer Koc¸
Keyword(s):  
Flow Stress ◽  
Optical Measurement ◽  
Measurement Techniques ◽  
Material Behavior ◽  
Biaxial Stress ◽  
Dome Height ◽  
Bulge Test ◽  
Analysis Methods ◽  
Bulge Testing ◽  
Hydraulic Bulge

Hydraulic bulge testing is a material characterization method used as an alternative to tensile testing with the premise of accurately representing the material behavior to higher strain levels (∼70% as appeared to ∼30% in tensile test) in a biaxial stress mode. However, there are some major assumptions (such as continuous hemispherical bulge shape, thinnest point at apex) in hydraulic bulge analyses that lead to uncertainties in the resulting flow stress curves. In this paper, the effect of these assumptions on the accuracy and reliability of flow stress curves is investigated. The goal of this study is to determine the most accurate method for analyzing the data obtained from the bulge testing when continuous and in-line thickness measurement techniques are not available. Specifically, in this study the stress-strain relationships of two different materials (SS201 and Al5754) are obtained based on hydraulic bulge test data using various analysis methods for bulge radius and thickness predictions (e.g., Hill’s, Chakrabarty’s, Panknin’s theories, etc.). The flow stress curves are calculated using pressure and dome height measurements and compared to the actual 3-D strain measurement from a stereo optical and non-contact measurement system ARAMIS. In addition, the flow stress curves obtained from stepwise experiments are compared with the ones from above methods. Our findings indicate that Enikeev’s approach for thickness prediction and Panknin’s approach for bulge radius calculation result in the best agreement with both stepwise experiment results and 3D optical measurement results.

scholarly journals Study of the Hydraulic Bulge Test in T-shape Hydroforming Die

2015 ◽  
Vol 19 ◽  
pp. 70-76 ◽  
Author(s):  
Amir Ashrafi ◽  
Khalil Khalili
Keyword(s):  
Bulge Test ◽  
Hydraulic Bulge Test ◽  
Hydraulic Bulge

Strain Evaluation and Fracture Properties of Hetero-Epitaxial Single Crystal 3C-SiC Squared Membrane

2014 ◽  
Vol 806 ◽  
pp. 11-14
Author(s):  
Ruggero Anzalone ◽  
Giuseppe D'Arrigo ◽  
Massimo Camarda ◽  
Nicolo’ Piluso ◽  
Francesco La Via
Keyword(s):  
Large Deflection ◽  
Strain Tensor ◽  
Applied Pressure ◽  
Bulge Test ◽  
Phonon Modes ◽  
Breaking Strain ◽  
Test Technique ◽  
Raman Analysis ◽  
Fracture Properties ◽  
The Relationship

The following paper explores the development the bulge test technique combined with the micro-Raman analysis and a refined load-deflection model for high quality 3C-SiC squared-membranes. By the minimization of the total elastic energy, starting from the isotropic relation between the stress tensor and the strain tensor, it is possible to calculate the relationship between the maximum deflection and the applied pressure, in both regime of small and large deflection. From the measured breaking pressure through the refined model it is possible to evaluate the breaking strain of the membrane. Furthermore, the relationship between the measured shift of Raman Transverse Optical (TO) phonon modes and the total residual strain (Δa/a) within the epitaxial 3C-SiC layer was found.

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