The influence of surface grinding and microstructure on chloride induced stress corrosion cracking (SCC) behavior of 2304 duplex stainless steel has been investigated. Grinding operations were performed both parallel and perpendicular to the rolling direction of the material. SCC tests were conducted in boiling magnesium chloride according to ASTM G36; specimens were exposed both without extern...

Abstract Previous research has indicated that the surface wave transmission (SWT) method can be used to measure the depth of a single surface-breaking crack in concrete. In this paper, the authors extend the SWT method to evaluation of distributed cracks in concrete. First, scattering field of surface waves caused by distributed cracks in concrete was investigated using numerical simulation. Se...

OBJECTIVE The objective of our study is to analyse (with the help of scanning electron microscopes) the quality of the dental root surface and the appearance of dental cracks after performing apical preparations using two different types of ultrasonic tips. STUDY DESIGN We used 32 single-rooted teeth that underwent a root canal and apical resection. Afterwards, the teeth were divided into 4 g...

ID No: 65 ABSTRACT This research studies the self-healing potential of early cracks in cement-based materials incorporating carbonic anhydrase (CA) bacteria. CA bacteria can accelerate the CO2 hydrated reaction then transfer CO2 to HCO3 which can react with soluble Ca(OH)2 on the surface of specimens. Calcium carbonate deposits because of the reaction of HCO3 with Ca.This research studies the s...

Abstract In this study, the fracture mechanisms of Cr-coated Zr4 alloy samples were studied by in-situ tensile testing with high-resolution observations. Both original sample and pre-oxidized to study effects pre-oxidation on cracking failure behavior. For sample, increase strain, multiple surface cracks dominant less interfacial formed, indicating good strength Cr coating. samples, there was a...

Non-destructive detection and evaluation of invisible cracks in metal structures is an important matter in several critical environments including ground transportation, air transportation and power plants. In this paper, a high-Q near-field Microwave probe is designed and fabricated using defected ground structures for surface and subsurface crack detection in metal structures. For this purpos...

Electro deposition of NiFeWS thin films was carried out from diammonium citrate bath at a constant current density (1 A/dm 2 ) and controlled pH of 8 by varying the citrate bath concentration(0.2, 0.3, 0.4, 0.5 mol / lit). Physical properties such as surface morphology, microstructure and magnetic properties such as coercivity, saturation magnetization and magnetic flux density were investigate...

In this paper, rotating bending fatigue tests of 2024-T4 Al alloy with different oxide coatings were carried out. Compared to the uncoated and previously reported oxide coatings of aluminum alloys, the fatigue strength is able to be enhanced by using a novel oxide coating with sealing pore technology. These results indicate that the better the coating surface quality is, the more excellent the ...

Mg(OH)2 conversion coatings were formed on an Mg-2Zn-0.5Mn-Ca-Ce alloy via hydrothermal method at three different synthesizing temperatures (160, 170 and 180 ̋C). The effect of synthesizing temperature on microstructure and electrochemical property of the coatings were systematically studied. With increasing synthesizing temperature, the coating became thicker due to the faster reaction and dep...

We have developed a low frequency theory for scattering from surface cracks. For the case of halfpenny shaped surface cracks, we are able to relate the reflection coefficient of a Rayleigh wave incident on the crack with the crack size as well as the fracture stress of a sample with the crack in it. Comparisons of the theoretical predictions for the fracture stress with the actual fracture stre...