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PL
W artykule przedstawiono wyniki badań własnych dyfuzyjności cieplnej aluminium Al. 0. 9999 oraz stopu aluminium AW-6063, oznaczanego również jako PA38. Badania przeprowadzono przy zastosowaniu zmodyfikowanej metody impulsowej, w zakresie temperatury od 20 do około 450°C.
EN
The article presents the results of thermal diffusivity investigations of aluminum Al 0. 9999 and an AW-6063 aluminum alloy also called PA38. The tests were performed using a modified pulse method in a temperature range from 20 to about 450 °C.
EN
Transient heat transfer is studied and compared in two plane-parallel composite walls and one EPIDIAN 53 epoxy resin wall acting as a matrix for both composites. The first of the two walls is made of carbon-epoxy composite; the other wall is made of glass-epoxy composite, both with comparable thickness of about 1 mm and the same number of carbon and glass fabric layers (four layers). The study was conducted for temperatures in the range of 20-120 °C. The results of the study of thermal diffusivity which characterizes the material as a heat conductor under transient conditions have a preliminary character. Three series of tests were conducted for each wall. Each series took about 24 h. The results from the three series were approximated using linear functions and were found between (0.7-1.35) x 10-7m2/s. In the whole range of temperature variation, the thermal diffusivity values for carbon-epoxy composite are from 1.2 to 1.5 times higher than those for the other two materials with nearly the same thermal diffusivity characteristics.
PL
Przedstawiono wyniki badań laboratoryjnych wpływu otoczenia kabla na warunki propagacji impulsów w ekranie linii współosiowej.
EN
The paper presents results of laboratory research on influence of cable environment on conditions of pulse propagation in shield of coaxial line.
PL
W artykule przedstawiono wyniki badań dotyczących procesu osadzania siarczku kadmu metodą elektrochemiczną na podkładkach miedzianych. Celem pomiarów było dobranie odpowiednich parametrów procesu osadzania półprzewodnika. Doświadczenie przeprowadzono używając roztworu chlorku kadmu oraz tiosiarczanu sodu o pH = 3. Proces elektrolizy przeprowadzano w warunkach potencjostatycznych oraz stosując metodę impulsową. Pierwszy sposób nie przyniósł oczekiwanich rezultatów, natomiast zastosowanie drugiej metody zakończyło się powodzeniem. Uzyskany osad poddano analizie pierwiastkowej i fazowej, które potwierdziły obecność siarczku kadmu na podkładce miedzianej. Dodatkowo przeprowadzono obserwacje morfologii uzyskanych osadów za pomocą elektronowego mikroskopu skaningowego.
EN
This article presents results of research concerning deposition of cadmium sulfide on copper by an electrochemical method. This study was primarily designed to determine proper parameters of deposition the semiconductor. Experiment was carried out using acid aqueous solutions containing cadmium chloride and sodium thiosulfate with pH = 3. Process of electrolysis was carried out by a potentiostatic and pulse methods. The first one hasn't provided expected results whereas second one has terminated with success. The deposited coatings were investigated by phase and elementary analysis which confirmed presence of cadmium sulfide on copper. The morphology of the CdS thin films were analyzed using scanning electron microscopy.
PL
W artykule przedstawiono wpływ grubości próbki na mierzoną wartość dyfuzyjności cieplnej modyfikowanej żywicy epoksydowej. Badania dyfuzyjności cieplnej przeprowadzono metodą impulsu cieplnego. Wyniki badań eksperymentalnych wykazały, że grubość próbki badanej ma istotny wpływ na uzyskany wynik dyfuzyjności cieplnej.
EN
The article presents the effect of specimen thickness on measured value of thermal diffusivity of modified epoxy resin. The thermal diffusivity measurements were carried out using the heat pulse method. Experimental results showed that the specimen thickness considerably affects the obtained value of thermal diffusivity.
EN
Results of analysis of influence of transmission line non-uniformity on the precision of location of the fault using pulse methods is presented. The measurements and computer simulations were carried out in order to determine the magnitude of the transmission line non-uniformity which is possible to recognize, especially the dielectric constant of isolation. The results of measurements of influence of external action such as compression, bending and temperature are also discussed.
7
EN
A pulse method for simultaneous determination of the specific heat and the thermal diffusivity of plastics by using double-layer sample "metal-plastics" has been presented. Investigations have been carried out using a sample made of polytetrafluoroethylene (PTFE) of diameter 12 mm with glued molybdenum foil of thickness 0.1 mm. The temperature range of investigations is 290 - 400 K.
PL
Opisano sposoby lokalizacji miejsca uszkodzenia z zastosowaniem metody jednoimpulsowej w liniach zbudowanych z kabli łączonych równolegle.
EN
The paper describes fault location methods that use one pulse met lines with cables connected in parallel.
EN
A method of the thermal diffusivity measurement of the semitransparent materials for the laser pulse radiation is described. The paper also presents a laser flash laboratory apparatus used for the thermal diffusivity investigations. A pulse neodymium laser is utilised as a heat source. The method is based on the measurements of the temperature difference between two surfaces of a disc-like sample during the process of achieving the temperature equilibrium. The materials under testing were methyl polymethacrylate (PMM) and polytetrafluoroethylene (PTFE). Investigations were carried out within a temperature range of 300-360 K.
10
Content available remote A modified flash method for determination of thermal diffusivity in solids
EN
A modified version of the flash method of the thermal diffusivity measurement of solids is described. The method is based on the analysis of the temperature difference between two opposite surfaces of a disc-like sample, where one surface had surface heat generation. The paper also presents a laser flash laboratory apparatus, a procedure for the samples preparation under investigation, as well as the required conditions for the experiment. The method and the apparatus were tested by measurement the thermal diffusivity of nickel 0.999 for several temperatures within the range from 300 to 1000 K. For illustration, the investigation of thermal diffusivity characteristic, within the range from 300 to 1000 K, of the N18K9M5TPr alloy steel, is also presented. The error of the thermal diffusivity determination was estimated to be less than 6%.
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