Stjepan Jecic Rudolf J. Beer, Janos Kodvanj, Martin Fleischmann
SHRINKING OF POLYMERS IN TECHNICAL PROBLEMS CONSISTING OF TWO DIFFERENT PARTS DETERMINED BY 3D PHOTOELASTICITY USING GAMMA IRRADIATION

To solve spatial technical problems by three dimensional photoelasticity it is necessary to fix the optical effect in the model. In order to avoid the well known disadvantages of the classical freezing method ionising irradiation is used for that purpose. With this method it is not necessary to enlarge the scaling-factor for the displacement which is in some cases very important especially when shrinking is used to develop the fringe pattern. In addition fixation with ionising irradiation can be carried out without elevated temperatures. The most important advantage compared with the freezing method is given by the fact that Poisson’s ratio of the polymers is in this way practically the same as in the simple two dimensional photoelasticity. This is very important because using the classical freezing method temperature treatment above the glass temperature is needed and in this temperature range Poisson’s ration of the polymer is practically the same as in plasticized zones so that by using the classical freezing method it is not possible to distinguish between the elastic and the plasticized zones of the model. The mentioned features were already shown in case of two dimensional contact problem. New materials introduced by Beer at all opened additional possibilities in modelling more complex problems. However dealing with models consisting of two (or even more) different parts we have to keep in mind that shrinking in such models causes residual stresses and for that reason an accompanying rheological process is going on.

Vygantas Augutis, Darius Gailius, Arturas Milinskas
MEASUREMENT OF THE SHRINKING FORCE OF CATHODE RAY TUBE’S SHRINK FIT RIM BAND

The paper describes some Cathode Ray Tubes (CRT) Implosion Protection Systems (IPS) and their possible control methods.
The implosion of CRT (tube) is prevented by using the Shrink Fit Rim Band (SFRB) reinforcing the edge of the tube so that it cannot bulge outwards. The main parameter of SFRB is the shrinking force. Measurement of such a shrinking force is a very important SFRB quality control method herewith of safe CRT. In this paper we consider several methods of shrinking force measurement:
- Magnetization method;
- Barkhausen’s noise method;
- CRT imitator-measurer.
Magnetization method can be successfully used for the measurement of shrinking force. However, there have been found some regularities of this method, which partly limit its application in a number of cases. This method cannot be used when the shrinking force changes its direction. It is applicable only when controlled material is magnetized.
Barkhausen’s noise method is rather effective in the control of shrinking force. However as the Barkhausen’s noise depends not only upon stresses in material but also upon chemical and structural composition of material, there is a problem of calibration.
CRT imitator-measurer provides sufficient accuracy of measurement; therefore it can effectively measure the shrinking force. The device is successfully used in carrying out experiments in Ekranas Co.

Boris Katz, Liron Anavy, Irina Telent
EVALUATION OF FUNCTIONAL PARAMETERS MEASUREMENT’S ACCURACY FOR A "LEMON"/"BARREL" SHAPED BODY

These article sums our calculations and experiments of "lemon"/"barrel" shaped bodies; we’ve analyzed 4 methods for the measurements of the important parameters and calculated the uncertainty of each method.

Sonko Osawa, Toshiyuki Takatsuji, Tomizo Kurosawa
STEP-GAUGE CALIBRATION USING AN INTERFEROMETRIC COORDINATE MEASURING MACHINE AND THE UNCERTAINTY

There are many kinds of geometrical gauges used for calibration of machine tools and coordinate measuring machines (CMMs). A step-gauge is a kind of calibration gauge. It consists of many short gauge blocks and a base bar. Gauge blocks were directly calibrated by an interferometer using method of exact fraction. The method, however, does not apply to the calibration of step-gauges because of their complicated structure. The calibration works are very important missions in national metrology institutes (NMIs). We developed the step-gauge calibration system that consisted of a CMM and an interferometer. We describe the system scheme of a step-gauge calibration system using a conventional CMM combined with an interferometer and the evaluation of the measurement uncertainty. The uncertainty in measurement using this system is about 0.5 µm (k = 2) for 1-meter measurement.

Jae-Hwa Hong, Jeong-Mok Kim, Eun-Do Kim, Gi-Deok Park, Kyu-Sam Hwang, Soon-Ju Kwon
ON-LINE PHASE AND ALLOYING DEGREE MEASUREMENT SYSTEM FOR GALVANNEALED COATINGS

An on-line measurement system for phase fraction and alloying degree of galvannealed steel has been developed using an X-ray diffraction method. Intensities of diffraction peaks of Γ, δ, ζ and η iron-zinc phases were utilized for the determination of each phase fraction and alloying degree. Calibration curves were constructed using laboratory prepared standard reference samples and multiple regression technique. The system has been employed in POSCO’s galvannealing line at Kwang Yang Works for process monitoring.