نتایج جستجو برای: ultrasonic materials testing

تعداد نتایج: 782286  

2009
Raymond H. Puffer Daniel Walczyk Peter Devlin Jesse Adams

Completed unplanned but promising • experimentation on the use of ultrasonics for pressing of low-temperature (Nafion) MEAs. Submitted two publications for review based on • early unplanned experimentation and testing of low-temperature MEAs produced with both thermal pressing and ultrasonic pressing. Completed modifications of commercial ultrasonic • press and construction of custom tooling fo...

2004
B. Boro Djordjevic D. Cerniglia C. Cosenza

Non-contact ultrasonic, enables rapid testing of structures using ultrasonic tests that are not possible via conventional contact transducers. This paper reports on laser ultrasonic and air/gas coupled ultrasonic measurements that are performed remotely, do not require direct access to test area, do not need traditional ultrasonic coupling and do not have traditional C-scan fixture requirements...

Journal: :Ultrasonics 2009
M Molero I Segura M A G Izquierdo J V Fuente J J Anaya

The quality and degradation state of building materials can be determined by nondestructive testing (NDT). These materials are composed of a cementitious matrix and particles or fragments of aggregates. Sand/cement ratio (s/c) provides the final material quality; however, the sand content can mask the matrix properties in a nondestructive measurement. Therefore, s/c ratio estimation is needed i...

2008
Junjie CHANG Jiujun XU

In this paper, ultrasonic wave propagation in three phases (3P) of composite materials was investigated. The simulation was conducted by PZFlex analysis code, a time domain finite element program. The reflection and transmission characteristics with different shapes of middle layer between glass fiber and epoxy resin are investigated in order to understand basic ultrasonic behavior of energy di...

2005
J. Brožovský O. Matějka P. Martinec

In this paper, the non-destructive testing methods are analyzed in view of their usability in evalulation of the interlocking paving blocks’ compressive strength. Ultrasonic pulse method and impact method (Schmidt impact hammers) were chosen for testing. Testing methodology and way of the results processing considering requests of the national and European standards are described there. In addi...

2004
A. Apfel J. Moysan G. Corneloup B. Chassignole

In some austenitic stainless steel welds grains orientations cause deviation and splitting of the ultrasonic beam. It is especially true in the case of multipass welds when the remelting process after each pass causes complex solidification process. With the new model MINA (Modelling anisotropy from Notebook of Arc welding) we show that we are able to predict thoroughly grains orientations. Thi...

2012
A. Petrauskas D. Petrauskas

In this article application of direct and indirect ultrasonic methods for evaluating and measuring porous materials are reviewed. Ultrasonic waves, due to their physical properties and wide frequency range can successfully be applied when evaluating the porosity of materials. Ultrasonic methods have many advantages when comparing them with other, non-acoustic measurement methods, which are also...

2005
Bao Mi Thomas E. Michaels Jennifer E. Michaels

Successful in-situ monitoring of crack initiation and growth is a necessary prerequisite for applying ultrasonic methods to structural health monitoring. For conventional ultrasonic testing methods, a focused beam may be used to directly image the crack tip; however, this method is difficult to apply during fatigue testing because of access limitations and couplant contamination issues. However...

Structural health monitoring (SHM) systems operate online and test different materials using ultrasonic guided waves and piezoelectric smart materials. These systems are permanently installed on the structures and display information on the monitor screen. The user informs the engineers of the existing damage after observing signal loss which appears after damage is caused. In this paper health...

2005
A. J. W HITTLE

Calibration and Reference Blocks ................................................................. 7 Longitudinal Wave Probes ............................................................................. 7 Transverse Wave Probes ............................................................................. 10 Measurement of Steel Thickness ...........................................................

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید