On the measurement of true fracture strain of thermoplastics materials

2008 ◽  
Vol 27 (3) ◽  
pp. 284-295 ◽  
Author(s):  
Xinran Xiao
Keyword(s):  
Fracture Strain ◽  
True Fracture

scholarly journals Microstructure and Mechanical Properties of Nb and V Microalloyed TRIP-Assisted Steels

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 887
Author(s):  
Olli Oja ◽  
Ari Saastamoinen ◽  
Madan Patnamsetty ◽  
Mari Honkanen ◽  
Pasi Peura ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Retained Austenite ◽  
Fracture Strain ◽  
Intercritical Annealing ◽  
Isothermal Holding ◽  
Microstructural Properties ◽  
Transformation Induced Plasticity ◽  
True Fracture ◽  
Mechanical And Microstructural Properties ◽  
Holding Temperature

The intercritical annealing and isothermal bainitic processing response was studied for three Nb and V microalloyed Transformation-Induced Plasticity (TRIP)-assisted 980 MPa grade steels. Their mechanical and microstructural properties were compared to industrially produced TRIP 800 steel. Depending on the isothermal holding temperature and microalloying, the experimental steels reached properties comparable to the reference steel. The retained austenite content did not show direct correlation to elongation properties. Niobium was found to be more effective microalloying element than vanadium in increasing the elongation properties, which were investigated by measuring true fracture strain from tensile test specimens.

Ductile Fracture of a Marine Structural Steel based on HC-DSSE Combined Fracture Strain Formulation

2019 ◽  
Vol 56 (1) ◽  
pp. 82-93
Author(s):  
Sung-Ju Park ◽  
Kangsu Lee ◽  
Burak Can Cerik ◽  
Younghyn Kim ◽  
Joonmo Choung
Keyword(s):  
Ductile Fracture ◽  
Structural Steel ◽  
Fracture Strain ◽  
Strain Formulation

scholarly journals Comparison of Modified Mohr–Coulomb Model and Bai–Wierzbicki Model for Constructing 3D Ductile Fracture Envelope of AA6063

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Jianye Gao ◽  
Tao He ◽  
Yuanming Huo ◽  
Miao Song ◽  
Tingting Yao ◽  
...  
Keyword(s):  
Ductile Fracture ◽  
Fracture Criterion ◽  
Fracture Strain ◽  
Stress Triaxiality ◽  
Ductile Fracture Criterion ◽  
Forming Process ◽  
Tension Tests ◽  
Wide Range ◽  
Round Bar ◽  
Fracture Envelope

AbstractDuctile fracture of metal often occurs in the plastic forming process of parts. The establishment of ductile fracture criterion can effectively guide the selection of process parameters and avoid ductile fracture of parts during machining. The 3D ductile fracture envelope of AA6063-T6 was developed to predict and prevent its fracture. Smooth round bar tension tests were performed to characterize the flow stress, and a series of experiments were conducted to characterize the ductile fracture firstly, such as notched round bar tension tests, compression tests and torsion tests. These tests cover a wide range of stress triaxiality (ST) and Lode parameter (LP) to calibrate the ductile fracture criterion. Plasticity modeling was performed, and the predicted results were compared with corresponding experimental data to verify the plasticity model after these experiments. Then the relationship between ductile fracture strain and ST with LP was constructed using the modified Mohr–Coulomb (MMC) model and Bai-Wierzbicki (BW) model to develop the 3D ductile fracture envelope. Finally, two ductile damage models were proposed based on the 3D fracture envelope of AA6063. Through the comparison of the two models, it was found that BW model had better fitting effect, and the sum of squares of residual error of BW model was 0.9901. The two models had relatively large errors in predicting the fracture strain of SRB tensile test and torsion test, but both of the predicting error of both two models were within the acceptable range of 15%. In the process of finite element simulation, the evolution process of ductile fracture can be well simulated by the two models. However, BW model can predict the location of fracture more accurately than MMC model.

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 Study of Influence of Width to Thickness Ratio in Sheet Metals on Bendability under Ambient and Superimposed Hydrostatic Pressure

2021 ◽  
Vol 2 (3) ◽  
pp. 542-558
Author(s):  
Mohammadmehdi Shahzamanian ◽  
David Lloyd ◽  
Amir Partovi ◽  
Peidong Wu
Keyword(s):  
Hydrostatic Pressure ◽  
Stress Ratio ◽  
Fracture Strain ◽  
Stress Triaxiality ◽  
Volumetric Strain ◽  
Thickness Ratio ◽  
Sheet Metals ◽  
The Finite Element Method ◽  
Bending Strain ◽  
Good Agreement

The effect of the width to thickness ratio on the bendability of sheet metal is investigated using the finite element method (FEM) employing the Gurson–Tvergaard–Needleman (GTN) model. Strain path changes in the sheet with change in the width/thickness ratio. It is shown that bendability and fracture strain increase significantly by decrease in the width/thickness ratio. The stress state is almost uniaxial when the stress ratio (α) is close to zero for narrow sheets. Stress ratio is nothing but the major stress to minor stress ratio. This delays the growth and coalescence of micro-voids as the volumetric strain and stress triaxiality (pressure/effective stress) decrease. On the other hand, ductility decreases with increase in α for wider sheets. Fracture bending strain is calculated and, as expected, it increases with decrease in the width/thickness ratio. Furthermore, a brief study is performed to understand the effect of superimposed hydrostatic pressure on fracture strain for various sheet metals with different width/thickness ratios. It is found that the superimposed hydrostatic pressure increases the ductility, and that the effect of the width/thickness ratio in metals on ductility is as significant as the effect of superimposed hydrostatic pressure. Numerical results are found to be in good agreement with experimental observations.

scholarly journals Increase in the antioxidant content in biscuits by infusions or Prosopis chilensis pod flour

2021 ◽  
Vol 6 (1) ◽  
pp. 243-253
Author(s):  
Paula Andrea Conforti ◽  
Mariela Patrignani
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Fracture Stress ◽  
Fracture Strain ◽  
Gluten Free ◽  
Maize Starch ◽  
Prosopis Chilensis ◽  
Antioxidant Content ◽  
Fat Level ◽  
Increasing Demand

Abstract Nowadays there is an increasing demand for healthy biscuits. The reduction in sugar and fat level, as well as the addition of bioactive compounds, is positively associated with a healthy diet. In the present work, low-fat and low-sugar biscuits were prepared with infusions (mate, coffee, and tea) or with Prosopis chilensis pod flour (PPF). Biscuits were made with maize starch and wheat flour (gluten formulations) or with gluten-free ingredients (gluten-free). The colour, texture, and the antioxidant capacity were evaluated in dough and biscuits. Among the formulations prepared with infusions, the mate dough showed the lowest firmness (1.1 N (gluten)-24.3 N (gluten-free)). However, no significant differences were found in the fracture stress of the final products (P > 0.05). Mate gluten biscuits and PPF gluten-free biscuits showed the highest fracture strain (16.2 and 9.4%, respectively) and the lowest Young’s modulus (7.3 and 13.3 MPa, respectively) in their groups. The highest antioxidant activity was found in biscuits with mate (8.7 µmol FeSO4/g (gluten)-4.3 µmol FeSO4/g (gluten-free)). These values were three times higher than the ones found in the control biscuits (2.9 µmol FeSO4/g (gluten)-3.9 µmol FeSO4/g (gluten-free)). The present results showed that the antioxidant content in biscuits could be successfully increased with infusion addition.

scholarly journals Criteria of Ductile Fracture Strain

1972 ◽  
Vol 15 (90) ◽  
pp. 1507-1513 ◽  
Author(s):  
Moriya OYANE
Keyword(s):  
Ductile Fracture ◽  
Fracture Strain

Metrology of the photo-grid determination of fracture strain for a plate in bending

1968 ◽  
Vol 3 (2) ◽  
pp. 96-97
Author(s):  
R T Hartlen ◽  
L E Jones
Keyword(s):  
Circumferential Strain ◽  
Fracture Strain ◽  
Thickness Ratio ◽  
Grid Data ◽  
Fracture Location ◽  
Maximum Value

Aluminium plates (7/1 width/thickness ratio) were bent to fracture. Circumferential strain at fracture location (maximum value 0.26) was obtained by special plotting and extrapolation of (millimetre) photo-grid data.

Sign in / Sign up

Export Citation Format

Share Document