New Equation for the Plastic Correction Factor η forJ-Integral Determination from Test Results of Three-Point-Bend Specimens

2014 ◽  
Vol 3 (3) ◽  
pp. 20130053
Author(s):  
Marius Gintalas ◽  
Antanas Ziliukas ◽  
Robert A. Ainsworth
Keyword(s):  
Correction Factor ◽  
Test Results ◽  
Plastic Correction ◽  
Point Bend ◽  
New Equation

On the Reproducibility of Transducer Coupling for Acoustic Emission Testing

2006 ◽  
Vol 13-14 ◽  
pp. 117-124 ◽  
Author(s):  
James J. Hensman ◽  
C.V. Cristodaro ◽  
Gareth Pierce ◽  
Keith Worden
Keyword(s):  
Acoustic Emission ◽  
Test Results ◽  
Coupling Condition ◽  
Waveform Data ◽  
Three Point Bending ◽  
Emission Testing ◽  
Acoustic Emission Testing ◽  
Acoustic Emission Test ◽  
Point Bend ◽  
Ultrasonic Propagation

An acoustic emission test was simulated using a three point bend specimen and an artificial AE source. Waveform data was recorded as the sample was cyclically loaded in three point bending, and the cross correlation coefficient of the waveforms was used to measure the repeatability of the test. Results were twofold: the stress state of a specimen affects the ultrasonic propagation therein; and the coupling condition of a transducer may not remain constant during a test.

Determination Method of Elasto-Plastic Correction Factor of TA16 Titanium Alloy Based On RCC-M Code Methodology

2021 ◽  
Author(s):  
Xuejiao Shao ◽  
Juan Du ◽  
Liping Zhang ◽  
Hai Xie ◽  
Jun Tian ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Titanium Alloy ◽  
Numerical Calculation ◽  
Austenitic Stainless Steel ◽  
Constitutive Model ◽  
Correlation Coefficient ◽  
Correction Factor ◽  
Calculation Method ◽  
Plastic Correction ◽  
Numerical Calculation Method

Abstract In the code for nuclear equipment, the elasto-plastic correction factor KE is a correction factor when the stress range exceeds the yield limit for simplified elasto-plastic fatigue analysis. The parameters and expressions of KE for commonly used materials (such as austenitic stainless steel) are given in the RCC-M and ASME code, but the parameters of KE for titanium alloy materials is lacking. Based on the cyclic elasto-plastic constitutive model of Z2CND18.12 (nitrogen control) and KE parameters of austenitic stainless steel given in the code, considering various sensitive factors, a numerical calculation method for determining KE correlation coefficient is established. The elasto-plastic constitutive model of TA16 alloy with nonlinear kinematic hardening was established by the uniaxial tension, strain and stress cycling tests of TA16 titanium alloy. Based on the numerical calculation method of KE and the constitutive model of TA16 titanium alloy, the expression and correlation coefficient of KE for TA16 titanium alloy were determined.

scholarly journals Effect of Fly Ash as Cement Replacement on Chloride Diffusion, Chloride Binding Capacity, and Micro-Properties of Concrete in a Water Soaking Environment

2020 ◽  
Vol 10 (18) ◽  
pp. 6271 ◽  
Author(s):  
Jun Liu ◽  
Jiaying Liu ◽  
Zhenyu Huang ◽  
Jihua Zhu ◽  
Wei Liu ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Fly Ash ◽  
Binding Capacity ◽  
Chloride Ion ◽  
Chloride Content ◽  
Chloride Ions ◽  
Chloride Diffusion ◽  
Chloride Binding ◽  
Test Results ◽  
New Equation

This paper experimentally studies the effects of fly ash on the diffusion, bonding, and micro-properties of chloride penetration in concrete in a water soaking environment based on the natural diffusion law. Different fly ash replacement ratio of cement in normal concrete was investigated. The effect of fly ash on chloride transportation, diffusion, coefficient, free chloride content, and binding chloride content were quantified, and the concrete porosity and microstructure were also reported through mercury intrusion perimetry and scanning electron microscopy, respectively. It was concluded from the test results that fly ash particles and hydration products (filling and pozzolanic effects) led to the densification of microstructures in concrete. The addition of fly ash greatly reduced the deposition of chloride ions. The chloride ion diffusion coefficient considerably decreased with increasing fly ash replacement, and fly ash benefits the binding of chloride in concrete. Additionally, a new equation is proposed to predict chloride binding capacity based on the test results.

Creep Rupture Bending Test of 20 Percent Cold-Prestrained Ni-Fe-Cr Alloy Straight Tubes at 1100 F(593 C)

1981 ◽  
Vol 103 (4) ◽  
pp. 337-344 ◽  
Author(s):  
H. H. Woo ◽  
R. H. Ryder ◽  
K. H. Holko ◽  
R. F. Stetson
Keyword(s):  
Crack Initiation ◽  
Creep Rupture ◽  
Bending Test ◽  
Strain History ◽  
Test Results ◽  
Local Material ◽  
Initiation And Propagation ◽  
Nonuniform Stress Field ◽  
Point Bend ◽  
Four Point Bend Test

A four-point bend test was performed on 20 percent cold-prestrained Ni-Fe-Cr alloy tubes at 1100 F (593 C) to verify that creep rupture damage can be used to predict failure in a nonuniform stress field. Deflection control and acoustic emission techniques were used to detect crack initiation, strain gages were employed to record the strain history in the specimen, and a scanning electron microscrope was utilized to check crack initiation and propagation. Stress analyses were made using simplified and finite element methods. Comparison of test results and analyses concluded that creep rupture damage can be used to predict local material failure for structural components under multiaxial nonuniform loading conditions.

Adhesion Characteristics of Epoxy Molding Compound and Copper Leadframe Interface: Impact of Environmental Reliability Stresses

2017 ◽  
Vol 2017 (1) ◽  
pp. 000304-000311
Author(s):  
Nishant Lakhera ◽  
Sandeep Shantaram ◽  
AR Nazmus Sakib
Keyword(s):  
Finite Element ◽  
Thermal Cycling ◽  
Test Results ◽  
Adhesion Test ◽  
Bend Testing ◽  
Molding Compound ◽  
Point Bend ◽  
Cost Implications ◽  
Microelectronic Package ◽  
Bare Copper

Abstract Delamination at the mold compound and leadframe interface is the most common failure mode observed during processing and qualification of the microelectronic package. Mold compound to leadframe delamination is typically observed after environmental reliability stresses like: moisture preconditioning and reflow, air-to-air thermal cycling, biased highly accelerated stress etc. Leadframe based packages constitutes majority of microelectronic packages that are manufactured today, which makes mold compound/leadframe interface of great interest requiring thorough understanding of the adhesion characteristics and its evolution as a function of reliability stresses. This study used four-point bend testing to evaluate the adhesion strength of commercially available mold compound to bare copper and silver plated copper leadframes exposed to automotive grade environmental stresses. Results show that adhesion of mold compound to silver plated leadframes is significantly lower than adhesion to bare copper leadframes. Results obtained from this study can be used to carefully select the qualification reliability stresses to prevent overstressing the package and causing failures related to wire bond cracking, delamination etc., which have significant time and cost implications. Finite element simulations were also performed to validate the empirical adhesion test results and can be extended to full package level models to enable delamination prediction.

Novel Approach of Sucker Rod Pump Unit Balance Determination and Monitoring

2021 ◽  
Author(s):  
Yuzar Aryadi ◽  
Azis Hidayat ◽  
Hilman Lazuardi ◽  
Syahroni Isnanto ◽  
Bonni Ariwibowo ◽  
...  
Keyword(s):  
Correction Factor ◽  
Electrical Parameter ◽  
Standard Procedure ◽  
Parameter Distribution ◽  
Well Performance ◽  
Optimization Software ◽  
Sucker Rod ◽  
Sucker Rod Pump ◽  
Pumping Unit ◽  
New Equation

Abstract SCADA optimization platform is implemented to monitor and evaluate well performance. For Sucker Rod Pump, SCADA Optimization Software can be used to monitor the unit balance and gearbox torque. In some ways, not all required well configuration data for SCADA Optimization Software to do a calculation of counterbalance torque (CBT) for pumping unit balance and gearbox torque evaluation are available. Standard field Counterbalance Effect (CBE) measurement might be performed to calculate the CBT value. However, this standard procedure is limited to well that run on balance condition. For well with unbalance condition, the measured CBE needs to be adjusted by a correction factor which the equation will be presented in this paper. The corrected CBE value from the new equation is then inputted to the SCADA Optimization software to perform day-to-day real-time monitoring of pumping unit balance and gearbox torque. Derivation of the CBE correction factor equation is presented. Validation upon this new equation is performed by comparing the result with electrical measurement on the pumping unit motor. Using the calculated CBT from the new equation, SCADA Optimization Software performs gearbox torque and pumping unit balance analysis based on every collected dynamometer card. Calculated CBT from the new equation provided results in gearbox torque distribution pattern that match with measured electrical parameter distribution along the stroke. This CBT value assists SCADA optimization software to calculate pumping unit balance and gearbox torque. Alarm in the SCADA optimization software that coming from an anomaly on pumping unit balance and gearbox torque help operator to do preventive maintenance so that pumping unit component especially the gearbox could have longer run life.

Three- and Four-Point Bend Testing for Electronic Packages

2003 ◽  
Vol 125 (4) ◽  
pp. 556-561 ◽  
Author(s):  
Santosh Shetty ◽  
Tommi Reinikainen
Keyword(s):  
Bending Test ◽  
Electronic Packages ◽  
Reliability Model ◽  
Test Results ◽  
Printed Wiring Board ◽  
Reliability Models ◽  
Four Point Bending ◽  
Three Point Bend Test ◽  
Point Bend ◽  
Wiring Board

This study demonstrates the application of three-point and four-point bending tests for evaluating the reliability of chip scale packages under curvature loads. A three-point bend test is conducted on 0.5-mm-pitch chip-scale packages (CSPs) mounted on FR4 (Flame Retardant) substrates. This test is simulated by using the finite element method and the results are calibrated experimentally to formulate a reliability model. A three-point bend scheme is an ideal choice for generating reliability models because multiple packages can be tested under multiple loads in a single test. This reliability model can be used to predict the durability of the packages in the real product under any printed wiring board (PWB) curvature loading conditions. A four-point bending simulation is also demonstrated on the test substrate. Four-point bending test is an ideal method for testing a larger sample size of packages under a particular predefined stress level. This paper describes the bending simulation and testing on packages in a generic sense. Due to the confidentiality of the test results, the package constructional details, material properties, and the actual test data have not been presented here.

Influence of Strain Rate on Mechanical Properties of Shape Memory Alloy

2011 ◽  
Vol 467-469 ◽  
pp. 585-588 ◽  
Author(s):  
Zhen Qing Wang ◽  
Hong Shuai Lei ◽  
Bo Zhou ◽  
Yu Long Wang ◽  
Chen Zhang
Keyword(s):  
Mechanical Properties ◽  
Shape Memory Alloy ◽  
Strain Rate ◽  
Shape Memory ◽  
Critical Stress ◽  
Transformation Process ◽  
Test Results ◽  
Stress Strain ◽  
Loading Tests ◽  
New Equation

The influence of strain rate on mechanical properties of Ni-Ti SMA wires was investigated by a series of uniaxial loading tests. The influence of strain rate on critical stress was discussed. During the transformation process, the slop of the stress-strain curves was increasing with the increase of strain rate. A new equation was developed to describe the change of residual train based on the test results.

Stress Analysis of 4-Point Bend Test for Thin Film Adhesion

2003 ◽  
Vol 778 ◽  
Author(s):  
Sassan Roham ◽  
Kedar Hardikar ◽  
Peter Woytowitz
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Classical Equation ◽  
Strength Properties ◽  
Test Results ◽  
Element Analysis ◽  
Film Adhesion ◽  
Thin Film Adhesion ◽  
Point Bend ◽  
Low K

AbstractFour point bend (4PB) tests are currently used to characterize the adhesive strength of thin films. Of particular interest are low k films whose strength properties are normally less than traditional dielectrics. A finite element analysis (FEA) of a 4PB specimen is conducted in order to better understand the results and limitations of such testing. We discuss the classical equation used to convert 4PB test data into fracture energy and have validated this classical formula using finite element analysis. We also present a theory that explains one possible reason for the occurrence of anomalous test results where the film fails in a cohesive rather than an adhesive mode.

Experimental Research on Fracture Toughness of High Grade Line Pipe

2012 ◽  
Vol 525-526 ◽  
pp. 425-428
Author(s):  
Qing Ren Xiong ◽  
Jian Xun Zhang ◽  
Yao Rong Feng ◽  
Hai Tao Wang ◽  
Qiu Rong Ma ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Test Results ◽  
Crack Tip Opening Displacement ◽  
Opening Displacement ◽  
Line Pipe ◽  
Propagation Resistance ◽  
Crack Propagation Resistance ◽  
Initiation And Propagation ◽  
Point Bend ◽  
Crack Tip Opening

Crack tip opening displacement (CTOD) tests were carried out on different positions of X70, X80 and X100 pipe by three-point bend testing method. The results show that the crack propagation resistance and the tear modulus of base metal, heat affected zone (HAZ), and weld of X70 and X80 pipe are larger than that of X100 pipe. At the same time,The initial CTOD values and the CTOD values withmaximum load of X70 and X80 pipe are larger than that of X100 pipe.The test results suggest that the fracture toughness, crack initiation and propagation resistance of theX70 and X80 pipe are greater than that of X100 pipe, and the mechanismis analyzed finally.

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