Ultrasonic Testing (UT) uses high frequency sound energy to conduct examinations and make measurements. Ultrasonic inspection can be used for flaw detection/evaluation, dimensional measurements, material characterization, and more. To illustrate the general inspection principle, a typical pulse/echo inspection configuration as illustrated below will be used.

A typical UT inspection system consists of several functional units, such as the pulser/receiver, transducer, and display devices. A pulser/receiver is an electronic device that can produce high voltage electrical pulses. Driven by the pulser, the transducer generates high frequency ultrasonic energy. The sound energy is introduced and propagates through the materials in the form of waves. When there is a discontinuity (such as a crack) in the wave path, part of the energy will be reflected back from the flaw surface. The reflected wave signal is transformed into an electrical signal by the transducer and is displayed on a screen. In the applet below, the reflected signal strength is displayed versus the time from signal generation to when a echo was received. Signal travel time can be directly related to the distance that the signal traveled. From the signal, information about the reflector location, size, orientation and other features can sometimes be gained.

Ultrasonic Inspection is a very useful and versatile NDT method. Some of the advantages of ultrasonic inspection that are often cited include:


* It is sensitive to both surface and subsurface discontinuities.
* The depth of penetration for flaw detection or measurement is superior to other NDT methods.
* Only single-sided access is needed when the pulse-echo technique is used.
* It is highly accurate in determining reflector position and estimating size and shape.
* Minimal part preparation is required.
* Electronic equipment provides instantaneous results.
* Detailed images can be produced with automated systems.
* It has other uses, such as thickness measurement, in addition to flaw detection.

As with all NDT methods, ultrasonic inspection also has its limitations, which include:

* Surface must be accessible to transmit ultrasound.
* Skill and training is more extensive than with some other methods.
* It normally requires a coupling medium to promote the transfer of sound energy into the test specimen.
* Materials that are rough, irregular in shape, very small, exceptionally thin or not homogeneous are difficult to inspect.
* Cast iron and other coarse grained materials are difficult to inspect due to low sound transmission and high signal noise.
* Linear defects oriented parallel to the sound beam may go undetected.
* Reference standards are required for both equipment calibration and the characterization of flaws.

The above introduction provides a simplified introduction to the NDT method of ultrasonic testing. However, to effectively perform an inspection using ultrasonics, much more about the method needs to be known. The following pages present information on the science involved in ultrasonic inspection, the equipment that is commonly used, some of the measurement techniques used, as well as other information.

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TEMEA research project ensures quality of electronic components in the automotive industry

Under the leadership of Fraunhofer FOKUS and with financial support from the Investitions­bank Berlin, the TEMEA project – Test Specification Technology and Methodology for Embedded Real Time Systems in the Automobile – has now taken up its work.

The main aims of the TEMEA project are to meet current and future demands for Quality Assurance in the automotive industry through the development and provision of standardizable testing technologies, and also to substantially lower production costs. Alongside the Fraunhofer Institutes FOKUS and FIRST, the other project partners include IT Power Consultants, Testing Technologies IST GmbH, Fourth Project Consulting and the University of Göttingen.


The project will run for three years; first results are expected in fall 2008.

“In spite of intensive efforts on the part of automobile manufacturers and their suppliers, no solutions have yet been found for dealing with problems arising from the testing and Quality Control of increasingly complex, increasingly networked systems,” says Prof. Dr. Ina Schieferdecker, TEMEA project manager at the Fraunhofer Institute FOKUS, talking about the project background. “For instance, test specifications for test systems and test solutions – many of which are proprietary – cannot be reused – neither between the original equipment manufacturer and supplier nor on a cross-project basis within the company. This leads to an unnecessarily high workload in terms of test specification and implementation, inhibits communication between producer and supplier and prevents reuse of existing test artifacts. The bottom line is that the quality of the whole vehicle suffers.”

The approach adopted by the TEMEA project is specially tailored to meet requirements-driven systematic testing of electronic components and their integration in the automobile. Based on the standardized testing technology TTCN-3, the TEMEA project seeks to develop a uniform test specification technology consisting of textual and graphical means of description for test specification, a flexibly adaptable test implementation and runtime environment, and a configured testing methodology that will satisfy the needs of suppliers and major manufacturers alike. An approach of this kind – which promises to raise the efficiency of Quality Assurance processes for software-intensive systems through standardizable technology and thus to lower their production costs – is something completely new for the automotive industry. A further special feature of the project is that it also covers current automotive industry standards such as AUTOSAR. The main project areas are

• integrated testing of discreet and continuous behavior,
• cross-platform exchange of test definitions (MiL/SiL/HiL),
• support across the whole testing and integration cycle,
• analysis of real-time and reliability requirements,
• testing of AUTOSAR components, and analysis of test quality.

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Other than as a source of light, rays of light radiated from the car also became alert to other vehicles. However, if the condition is less good, when the rainy season can arise in the dew light car.

If you want to turn, reduce speed or stop, for example, a rider or winking light rays as a means to communicate with other vehicles. For that, the lamps shining car should be light. Do not dimmed a bit, especially out at all.

One cause of the light rays can interfere with the car is moisture. Although only a vapor, the moisture to sneak in the lamp can be with the car.

Besides dim ray emission from the bulb, dew or moisture can cause the bulbs drop out, especially if moisture or water vapor to the cables to trigger short circuit time dialiri electricity.

Therefore, try to check the lamp of your car. If there is dew or moisture in it, most likely mica and spools in conditions that are less good. While handling, with the gracious light cover, and to dry clean using a rag and spray with the air compressor or hair dryer (hair dryer).

For a more satisfactory results, we recommend to replace the mica and seals in car lamps with its a new. Seal less, in general meeting occurred because of the age.

The older age of the vehicle, the seal is generally less elastic (hard). Moreover, if the vehicle is often parked in the summer. The mica is so, the old age of the vehicle and the more often exposed to hot temperatures, the possibility of cracked or broken the greater.

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