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Extending the durability of functioning of the sensitive elements of radiation indicators and increasing their reliability and safety are the main requirements for producers of modern radiation reconnaissance and monitoring devices. The proposed solutions for construction improving of products provide for the usage of optical fibers and the corresponding formation of loop-shaped channels in the finished sensitive polymer element. Potential possibilities of using magnetic abrasive polishing for finishing channel surfaces are considered. For the chosen construction of the polishing head, the material and form of the powder particles composition and the process parameters are proposed. The effect of the frequency and amplitude of vibration of abrasive particles on the depth of their penetration into the surface layer of the polymer is investigated. It has been determined that the widest possibilities of using powders of the composition Fe - C - Si - Ti with a diameter of d = 50 – 400 μm have a mode when the pressure of the air flow by feeding particles is maintained at a level of 1 atm, the magnetic induction of the field in the working gap is 0.8 T, the vibration amplitude of the particles is a = 0.4 mm, and the vibration frequency varies in the range f = 25 – 30 Hz, Подовжити довговічність функціонування – головна вимога до виробників сучасних приладів радіаційної розвідки та контролю. Запропоновані рішення щодо вдосконалення конструкції виробів передбачають використання оптичних світловодів та відповідне формування канавок петлеподібного профілю у готовому чутливому полімерному елементі. Розглянуто потенційні можливості використання магнітно-абразивного полірування для фінішної обробки поверхонь канавки чутливих елементів дозиметрів з метою підвищення їх надійності та безпечності. Для вибраної конструкції полірувальної головки запропоновано матеріал та форму порошкової композиції і параметри процесу. Досліджено вплив частоти та амплітуди коливання часточок на глибину їх проникнення у поверхневий шар полімеру.

V diplomski nalogi so opisane metode eksperimentov in ugotovitve pri utrjevanju materiala Al 7075. Pri tem se uporabi dva principa, toplotno obdelavo s staranjem zlitine in udarno utrjevanje s kovinskimi kroglicami. Našo metodo dela bi lahko v grobem razdelili na tri dele. V prvem delu smo pripravili vzorce, jih toplotno obdelali pri različnih temperaturah in določili optimalno temperaturo staranja. V drugem delu smo vzorce udarno utrjevali in jim z mikroskopom določili hrapavost. V zadnjem delu pa smo vzorce razrezali, jih vložili v bakelit in jim izmerili trdoto po globini. Na koncu smo z mikroskopom analizirali nastalo mikrostrukturo. Po vsaki obdelavi smo tudi opravili XRD analizo, s katero smo lahko primerjali nastale zaostale napetosti pri različnih postopkih. Cilj in namen diplomske naloge je ugotoviti, kakšni so optimalni parametri toplotne obdelave in staranja aluminijeve zlitine Al7075. Hoteli smo tudi ugotoviti, kakšen vpliv na trdoto, hrapavost in zaostale napetosti ima udarno utrjevanje aluminijeve zlitine pri različnih toplotnih obdelavah. In the dissertation we described the experimental methodology and findings about peening of aluminium alloy Al 7075. Two principles apply in this method - thermal treatment for aging the alloy and shot-peening with shot particles. Our method of work is divided into three parts. In the first one we prepared the samples, treated them thermally at different temperatures and determined their optimal temperature for aging. In the second part we shot-peened the samples and determined their roughness under a microscope. In the last part we cut them, put them in bakelite and measure their stiffness. At the end we analyzed the microstructure under a microscope. After every treatment we did XRD analysis to compare the residual stresses between different treatments. The purpose of the assignment is to determine the optimal parameters of thermal treatment for aging aluminium alloy Al 7075. We wanted to determine the effects of shot-peening of aluminium alloy on stiffness, roughness and residual stress at different methods of thermal treatment.

Title: Nanoclusters coatings for biomedical applications Author: Radek Divín Department: Department of Macromolecular Physics (110. 32-KMF) Supervisor: RNDr. Ondřej Kylián, Ph.D. Abstract: The copper nanocluster films were prepared with the aid of the gas cluster aggregation source based on the principle of material sputtering from the magnetron target to the relatively high pressure of the working gas (Ar). The nanocluster films prepared in this way were subsequently overlapped with the layer of plasma polymer deposited by RF magnetron sputtering from the nylon polymer target in the atmosphere of the working gas (Ar, 2 Pa). A repetition of this procedure enabled to prepare nanocomposite layers having a multilayer character. These layers were subsequently investigated with regard to their morphology, chemical composition, surface wettability and optical properties. The chemical composition of the surface layer formed by nanocomposite films was determined by the X-ray photoelectron spectroscopy (XPS). It turned out that the chemical surface composition of prepared nanocomposites was not markedly influenced by the presence of the Cu nanoclusters. The morphology of prepared films was studied by the scanning electron microscopy (SEM) and the atomic force microscopy (AFM), which showed that the resulting...