Structural Aspects Revealed by SEM Investigations for 2024 Aluminum Alloys

2018 ◽  
Vol 16 (15) ◽  
pp. 21-24
Author(s):  
Florina Violeta Anghelina ◽  
Dan Nicolae Ungureanu ◽  
Carmen Popa ◽  
Elena Valentina Stoian ◽  
Ileana Nicoleta Popescu ◽  
...  
Keyword(s):  
Aluminum Alloys ◽  
Theoretical Basis ◽  
Test System ◽  
Test Methods ◽  
Test Method ◽  
2024 Alloy ◽  
New Knowledge ◽  
Structural Aspects

Abstract In this presentation are evidenced instrumental characterization by Electronic Scanning Microscopy (SEM) equipped with EDS / WDS of aluminum alloys such 2024 alloy with multiple synergistic purposes as: acquisition of new knowledge, increase the amount of information obtainable about the material, increasing the efficiency and the quality of the tests, characterization of special destination alloys and assessing their conformity with the specified requirements. In this direction, it requires both the knowledge the test methods (theoretical basis, test method, procedure relating to the method, quality assurance testing) as well material characteristics investigated. These aspects are necessary for test system design, and preliminary interpretation of experimental results.

Characterization of Absorbent Flow Rate in Towel and Tissue

2010 ◽  
Vol 5 (2) ◽  
pp. 155892501000500 ◽  
Author(s):  
Paul D. Beuther ◽  
Michael W. Veith ◽  
Kenneth J. Zwick
Keyword(s):  
Flow Characteristics ◽  
Test Methods ◽  
High Variability ◽  
Test Method ◽  
Fluid Absorption ◽  
X Ray ◽  
X Ray Imaging ◽  
Model Predictions

The quality of a paper towel is often judged based on how quickly it can wipe up a spill. However, the test methods currently available cannot repeatably measure significant differences in absorbent rate between samples. Recent round-robin testing evaluations by TAPPI and CEN organizations have shown that past methods, such as ASTM D5802–95 and TAPPI T561-pm [1], are unreliable due to high variability. The reasons for the lack of repeatability are unclear. The relation between the wicking mechanism and the fundamental absorbent properties needs to be better understood. This paper uses x-ray imaging to show the overall flow characteristics of fluid absorption within a towel, and compares the results to model predictions to show which parameters are important to the process. From this understanding, a revised test method is proposed that provides adequate statistical discernment of absorbent rate properties of tissue on a simple lab-bench scale device.

Analysis of the Test Method of Quartz Glass Optical Homogeneity

2017 ◽  
Vol 726 ◽  
pp. 414-418
Author(s):  
Bo Fu ◽  
Hui Wang ◽  
Zhu Feng Shao
Keyword(s):  
Quartz Glass ◽  
Measurement Accuracy ◽  
Test Methods ◽  
Test Method ◽  
Wavefront Aberration ◽  
Optical Homogeneity ◽  
Advantages And Disadvantages ◽  
Interference Measurement ◽  
Optical Quartz Glass

The optical quartz glass is widely applied in optical system , photo communications，inertial navigation，etc.It must have high optical homogeneity. Optical homogeneity of the optical quartz glass directly affects the wavefront quality of the optical transmission system, and changes the wavefront aberration of the system. How to accurately determine the optical homogeneity of the quartz glass is especially important. Currently，the method of test for optical homogeneity mainly used by interference principle. This paper analyzes various existing interference measurement method and test equipment. Summarized the advantages and disadvantages of various test methods，using range and measurement accuracy.

Study on Test Methods for Intelligence-Based Monitoring of Fresh Cement Concrete Quality

2013 ◽  
Vol 857 ◽  
pp. 3-9
Author(s):  
Zi Yi Hou ◽  
Peng Peng ◽  
Jin De Xie ◽  
Shao Peng Zheng ◽  
Ye Zhen Yuan
Keyword(s):  
Theoretical Basis ◽  
Cement Mortar ◽  
Test Methods ◽  
Current Data ◽  
Test Method ◽  
Cement Concrete ◽  
Intelligent Monitoring ◽  
Concrete Quality

A test method for monitoring of cement mortar quality has been devised and an empirical relational equation between cement mortar fluidity and torque has been worked out. A test method for monitoring of indoor fresh cement concrete quality has been devised and a relational equation between fresh cement concrete and torque has been worked out. A test method for monitoring of fresh cement concrete in a mixing plant has been devised and a relational equation between fresh cement concrete and current property has been worked out. By means of online observed torque and current data, relevant fluidity and slump can be predicted to provide test methods and relevant theoretical basis for intelligent monitoring of fresh cement mortar and cement concrete quality in actual engineering.

scholarly journals The Biological Safety of Condom Material Can Be Determined Using anIn VitroCell Culture System

2001 ◽  
Vol 23 (2) ◽  
pp. 51-59 ◽  
Author(s):  
N. A. Motsoane ◽  
E. Pretorius ◽  
M. J. Bester ◽  
P. J. Becker
Keyword(s):  
Test System ◽  
Test Method ◽  
Potential Health ◽  
Sexually Transmitted ◽  
Biological Safety ◽  
Latex Gloves ◽  
Short Term Exposure ◽  
Medical Materials ◽  
Hiv Aids

Latex products have long been recognized as a cause of latex protein allergy. The increased usage of latex gloves, with the consequent increased occurrence of latex allergies appears to have escalated with increasing awareness of the transmission of HIV–AIDS and other infections. The use of condoms as a means to prevent the transmission of STD's (sexually transmitted diseases) and HIV–AIDS has been widely promoted. Although extensive testing is done to evaluate the physical quality of condoms, no information is available regarding the biological safety of condoms. This study was undertaken to determine the effects of short‐term exposure to physiological levels of condom surface material on cell viability (MTT assay) and cell growth (crystal violet assay). A direct contact cell culture testing method (FDA test method F813‐83 used to evaluate the cytotoxic potential of medical materials and devices) was used. The modified test method was found to be a sensitive test system for the evaluation of the biological safety of condoms. This study reveals the importance of evaluating the biological safety of all condoms that are commercially available, because of the potential health risk that may be associated with prolonged use of certain types of condoms.

Characterization of Silicate Ceramics Using Ultrasonics Test Method

2014 ◽  
Vol 92 ◽  
pp. 194-202 ◽  
Author(s):  
Semra Kurama ◽  
Elif Eren Gültekin
Keyword(s):  
Physical Properties ◽  
Water Absorption ◽  
Bulk Density ◽  
Test Methods ◽  
Ultrasonic Test ◽  
Test Method ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Non Destructive

Non-destructive testing techniques are widely used for testing ceramic materials. In our studies, two different types of ultrasonic test methods (A-scan and C-Scan) were investigated as non-destructive testing methods for characterization of porcelain tiles. Tiles were sintered in different temperatures to change their porosity and density properties. By changing of ultrasonic time and velocity related with samples’ some physical properties (such as bulk density, apparent density, apparent porosity (%), water absorption (%)) inspected via contact A-scan ultrasonic test method. The results show that without necessity of traditional test methods, some physical properties of ceramics can be determined by using obtained ultrasonic velocity-bulk density, apparent density, apparent porosity (%) and water absorption (%) calibration plots. Additionally, various defects were inspected in samples by using water immersion ultrasonic C-scan method. These results supported this study to obtain the information about defects’ size and place in the ceramic tiles. To support this non-destructive method results scanning electron microscope (SEM) characterization was done and images give the information about the place of the defect.

An Alternative Approach for FRCM Matrix Tensile Strength Evaluation

2019 ◽  
Vol 817 ◽  
pp. 365-370 ◽  
Author(s):  
Alessandro Bellini ◽  
Marco Bovo ◽  
Andrea Incerti ◽  
Claudio Mazzotti
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Mechanical Characterization ◽  
Experimental Tests ◽  
Tensile Tests ◽  
Test Methods ◽  
Test Method ◽  
The Matrix ◽  
Flexural Tests

Structural retrofitting with composite materials proved to be an effective technique for rehabilitation of degraded or damaged masonry and concrete buildings. Nowadays, Fiber Reinforced Cementitious Matrix (FRCM) composites are widely used as externally bonded strengthening systems thanks to their high performance, low weight and easiness of installation. Several experimental tests and numerical studies are currently available concerning the tensile and bond behavior of FRCM systems, but a debated and still open issue concerns the methods for the mechanical characterization of the mortar used as matrix within the strengthening system. The present paper analyses and compares different test methods for determining the matrix tensile strength. Pure tensile and flexural tests have been carried out on different mortar matrix samples. In order to evaluate which is the most suitable value to be considered for a correct interpretation and modeling of the composite system, the experimental results obtained through flexural tests on standard mortar specimens have been compared with the outcomes obtained from direct tensile tests on FRCM coupons. The present study represents only a first step for the definition of the most appropriate test method for the mechanical characterization of the matrix used within FRCM strengthening systems.

scholarly journals Study and Characterization of EN AW 6181/6082-T6 and EN AC 42100-T6 Aluminum Alloy Welding of Structural Applications: Metal Inert Gas (MIG), Cold Metal Transfer (CMT), and Fiber Laser-MIG Hybrid Comparison

Metals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 441
Author(s):  
Giovanna Cornacchia ◽  
Silvia Cecchel
Keyword(s):  
Aluminum Alloys ◽  
Fiber Laser ◽  
Large Scale ◽  
Metal Transfer ◽  
Inert Gas ◽  
Cold Metal Transfer ◽  
Structural Applications ◽  
Cold Metal

The present research investigates the effects of different welding techniques, namely traditional metal inert gas (MIG), cold metal transfer (CMT), and fiber laser-MIG hybrid, on the microstructural and mechanical properties of joints between extruded EN AW 6181/6082-T6 and cast EN AC 42100-T6 aluminum alloys. These types of weld are very interesting for junctions of Al-alloys parts in the transportation field to promote the lightweight of a large scale chassis. The weld joints were characterized through various metallurgical methods including optical microscopy and hardness measurements to assess their microstructure and to individuate the nature of the intermetallics, their morphology, and distribution. The results allowed for the evaluation of the discrepancies between the welding technologies (MIG, CMT, fiber laser) on different aluminum alloys that represent an exhaustive range of possible joints of a frame. For this reason, both simple bar samples and real junctions of a prototype frame of a sports car were studied and, compared where possible. The study demonstrated the higher quality of innovative CMT and fiber laser-MIG hybrid welding than traditional MIG and the comparison between casting and extrusion techniques provide some inputs for future developments in the automotive field.

scholarly journals PENINGKATAN PEMAHAMAN KONSEP GERAK MENGGUNAKAN MEDIA CD DENGAN PENDEKATAN KONSTRUKTIVISTIK KELAS VII B SEMESTER 2 SMP KESATRIAN 1 SEMARANG TAHUN AJARAN 2009/2010

2012 ◽  
Vol 1 (2) ◽  
Author(s):  
Latifah Syayidah
Keyword(s):  
Action Research ◽  
Test Methods ◽  
Test Method ◽  
Constructive Approach ◽  
Classical Study ◽  
Main Item ◽  
Media Learning ◽  
Teacher Ability ◽  
Academic Year

The action research classes entitle ?óÔé¼?ôImprovement move conceptcomprehension using CD as media with constrictive approach class VIIB semester 2 SMP Kesatrian 1 Semarang in academic year 2009/2010?óÔé¼?Ø.The problems in this action research was how to improvement moveconcept comprehension using CD as media learning with constructiveapproach students class VII B in SMP Kesatrian 1 Semarang.?Thisresearch has purpose to know is there improvement move conceptcomprehension using CD as media with constructive approach thestudents class VII B in SMP Kesatrian 1 Semarang. Subject of thisresearch was students class VII B. The factors that researched in thisresearch was factor of students, it was result study of the students insubject IPA. The factor from the teacher , include preparation andcarrying out of learning process. Method of collecting data that used inthis research was observation and test methods. Test method that used isessay test method.The result of the first sickles evaluation learningmethod application using constructive approach could improving abilityconcept comprehension especially students class VII B semester 2 SMPKesatrian 1 Semarang in academic year 2009/010. This matter seen inpercentage classical study completeness from the first sickles 70.21%with average 67.87% has improvement in the second sickles 87.23%with average 72.76. The improve quality of the teacher ability inlearning IPA with percentage in the first sickles has average 85% hasimprove in the second sickles 90%. Based on this the action research,suggestion that submitted was following: 1) the teacher must applied CDas media with constructive approach because it could improved abilityof the students in finished main item move discussion, 2) constructiveapproach with CD as media must be socialization to the teacher ofsubject IPA in order that applied in learning class, 3) the headmastergive motivation and facility in order that the teacher of subject IPAusing learning innovative model to overcome the problem for thestudents.Key words: konstruktivistik, pemahaman konsep, gerak

scholarly journals Bulgarian students’ impulsivity differentiated by gender, age, and some scientific areas

2018 ◽  
Vol 11 (2) ◽  
pp. 138-147 ◽  
Author(s):  
Stanislava Stoyanova ◽  
Vaitsa Giannouli
Keyword(s):  
Social Sciences ◽  
Cognitive Style ◽  
Interaction Effect ◽  
Test System ◽  
Test Method ◽  
Male Students ◽  
Social Sciences And Humanities ◽  
A Minor ◽  
Main Effects

Impulsivity is opposed to reflexivity as a cognitive style. This study investigated the frequency distribution of impulsivity in Bulgarian students, as well as some socio-demographic (gender, age, and some scientific areas – social sciences and humanities, as well as sport) differences in impulsivity. Impulsivity opposed to Reflexivity was assessed by means of a sub-scale of the computerized test method Attitude towards Work from Vienna Test System among 141 Bulgarian students. The results revealed slightly more frequent impulsivity than reflexivity in Bulgarian students, but not any gender, age or scientific areas main effects on impulsivity/reflexivity, only their interaction effect, such that younger male students in sport were more impulsive than older male students in sport. A minor trend was found reflexivity to increase with longer sports practice. These findings may indicate the quality of taken decisions in youth.

scholarly journals Influence of the Test Method on the Characterization of the Fatigue Delamination Behavior of a Composite Material under Mixed Mode I/II Fracture

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1788 ◽  
Author(s):  
Antonio Argüelles ◽  
Clara Rocandio ◽  
Silvia Rubiera ◽  
Isabel Viña ◽  
Jaime Viña
Keyword(s):  
Composite Material ◽  
Energy Release Rate ◽  
Energy Release ◽  
Release Rate ◽  
Mixed Mode ◽  
Fatigue Loading ◽  
Test Methods ◽  
Test Method ◽  
Mode I

Composite materials manufactured by overlapping plies with certain specific geometries are likely to lose part of their strength due to the presence of internally delaminated regions. The aim of this paper is to experimentally evaluate the generation and propagation of these interlaminar cracks in a carbon-epoxy composite material subjected to fatigue loading under mixed mode I/II fracture. Two different test methods were used for this purpose: The standardized mixed-mode bending (MMB) test and the asymmetric double cantilever beam (ADCB) test, with the goal of exploring the viability of the ADCB test as a simpler alternative to perform than the MMB test, especially in fatigue testing. With this aim in mind and after prior static characterization of the material in which the critical values of the energy release rate were determined under both test methods, the levels of the energy release rate to be applied in fatigue tests were defined for two mode mixity ratios, GII/Gc = 0.2 and 0.4 (0.34 ADCB), and a fatigue loading ratio, R = Gmin/Gmax = 0.1. The G-N fatigue onset curves were subsequently obtained from these experimental data. The most relevant result of the study is that the fatigue limits obtained using the MMB method are generally more conservative than those obtained via the ADCB method.

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