This thesis deals with the anodic oxidation of aluminum and its alloys. The work consists of two parts. The first one is focused on more detail description of anodic oxidation process itself and theoretical description of the technological process anodic oxidation. The second part is more practically oriented. It compares two different lines for anodizing, and examines factors that affect the final appearance of the surface layer during anodizing welded joints.

The thesis aims for the surface treatment of materials using electron beam. It includes a literary research describing physical principle and properties of the electron beam. This research also presents possible influencing of the beam and describes the construction of the device that generates the beam. Various applications of the electron beam for the material treatment are presented in the second part of the paper. Within this thesis an experiment with the heat treatment of the steel surface by the electron beam has been realized. The experiment was aimed at creating a layer as deep as possible without melting the surface. The results and their evaluation are presented in the experimental part of the thesis. The attention is also paid to selected process parameters.

The diploma thesis on the selection of appropriate technology to produce the welded construction of electric boiler JE6 / 12 aims to evaluate available production technologies and choose the most suitable of them. Choosing the technologies focuses primarily on those that are available at Slokov. Due to the connection of the welding robot to the production, it is necessary to consider the overall connection of the production and the high accuracy of the production. The individual methods of production, material separation, welding, bending and surface treatment are first theoretically analyzed and their advantages, disadvantages and parameters are summarized. Subsequently, it is practically tested individual technologies for a representative part and it evaluates the achieved parameters and economics of production. With the results obtained, the most suitable technologies are selected. With the selection of technologies, there is a need for a change in design and production parameters. Changes and modifications to the design describe another point. To achieve maximum efficiency and quality of production, a welding robot is used to make welds. The description of the production, modifications and overall design of the robot describes the next point of this work. The last part summarizes the economics of selected production technologies and details the technological process. The aim of the thesis is to design such technologies that will be advantageous from the point of view of the economy and from the perspective of the available possibilities of the company.

Polysaccharides constitute an important source of raw materials for the packaging industry today. Polysaccharides have good natural barrier properties which are necessary for packaging films. Cellulose is the forerunner among renewable polymers for such applications. Hemicelluloses represent a new interesting breed of barrier materials. We have chosen to work with the hemicellulose O-acetyl-galactoglucomannan (AcGGM). The high water solubility of this particular hemicellulose extracted from process waters is both an advantage and a limiting factor. However, through the right modification, the water sensitivity of AcGGM can be regulated. This thesis presents four ways to modify AcGGM: (i) benzylation, (ii) plasma surface treatment followed by styrene addition, (iii) vapor-phase (VP) surface grafting with styrene, and (iv) lamination of an unmodified film with a benzylated material. The most important methods of analysis of the films produced include contact angle measurement, dynamic mechanical analysis under moisture scan, and oxygen gas permeability measurement. It was found that unmodified AcGGM films have low oxygen permeability at intermediate relative humidity (50 % RH) and good dynamic mechanical properties over a wider humidity range. Films of benzylated material (BnGGM) exhibited a decrease in oxygen permeability at lower humidity but showed better tolerance to higher humidities and indicated better dynamic mechanical behavior than AcGGM films. Lamination proved to be the most promising technique of modification, combining the good gas barrier properties of AcGGM films with the moisture-insensitivity of the BnGGM films. / QC 20101117

The current Swedish building code (Boverkets Byggregler, BBR) is very strict regarding fire-safety in high-rise timber structures because of the heightened risk of fast flame spread or structural failure in case of fire. Fire safety solutions, that are used in timber structures must therefore be optimal to contain flames from spreading in the event of fire. The current building code requires that load-bearing elements must withhold their load-bearing capacity for 60 minutes under fire. The purpose of this study was to research the effect that different fire-retardant surface treatments, have on fire protection of a load bearing, laminated timber element. Thereafter, a short analysis was made on the environmental impact of the fire-retardant surface-treatments in question and finally, a cost analysis and comparison were conducted with regard to different fire-safety solutions such as fire-resistant gypsum board and a combination of fire-resistant gypsum board and stone-wool. The methods used in this study are a combination of theoretical reviews and theoretical calculations. A theoretical review was conducted in order to collect the information needed to understand the behavior of timber under fire, the impact of fire-resistant surface treatments on fire protection, and the environmental impact of the actual surface treatments. Therefore, a series of theoretical calculations were made in accordance with European standards (Eurocodes) in order to present the impact in numbers. The calculations made were concerning a laminated timber beam with the dimensions of 145 x 450 x 6000 [mm] and took into account the remaining cross-section of the timber element under various timestamps during fire with regard to fire-stage, charring-rate, and fire coating. The results of this study indicate that the moment-capacity and shear-capacity of an untreated beam decrease constantly under fire and does not fulfill the requirements of the Swedish building code. Thereafter, in case that the same timber beam is fire-treated with a fire-retardant surface treatment. The moment-capacity is observed to increase in the first stage of fire, were the fire-protection of the surface-retardant treatment is still in action. Therefore, after fire-protection ceases, the moment-capacity of the timber beam is calculated to decrease in different rates with regard to fire-stage. The shear capacity of the treated beam is calculated to decrease under fire with a time-displacement of 30 & 60 minutes in comparison to the untreated element. The conclusions are that the studied surface treated timber beam and the actual fire treatments fulfill the requirements of the Swedish building code. Have insignificant environmental impact and are in comparison to other solutions cheaper.

The treatment of polymer surfaces by low pressure plasmas is of technological interest in a variety of applications for modification and functionalisation. Until now the interactions of the individual plasma species (especially electrons) with polymeric material have not been subject of a microscopic study.In an anticipated chapter the inner plasma parameters were characterised by Langmuir probe measurements, leading to a precise knowledge about the density and energy distributions of plasma electrons and ions. The values for electrons were later used for an exclusive treatment with this species. The main part of this thesis describes and interprets the chemical composition after UV, plasma and electron treatment by x-ray photoelectron spectroscopy (XPS), structural changes by atomic force microscopy (AFM) and their combination to distinguish the fundamental interactions with polyethylene and polypropylene surfaces. It was found that all treatments show specific modification behaviour according to the chemical composition, topography and modification depth. For an argon microwave discharge, the plasma effects can also be obtained by a combination of UV and electron treatment. Fundamental radical reactions have been traced indirectly by chemical derivatisation as well as their passivation reactions through cross-linkage and the creation of double bonds.

L'objectif de notre travail est de développer un composite acier/polymère épais qui vise à apporter l'allègement de structure. Ce produit doit valider tous les tests classiques de l'automobile, notamment l'emboutissage, la mise en peinture, la tenue entre -40 ºC et 80 ºC, l'antigravillonage et la corrosion. Il est donc primordial d'avoir une adhésion suffisante pour permettre au composite de supporter les contraintes générées lors de la mise en oeuvre et les phénomènes de vieillissement en milieux hostiles. Dans notre cas, le polymère utilisé est un bicouche de 300 μm d'épaisseur. Il est constitué d'une couche adhésive de polypropylène greffé anhydride maléique et d'une couche de renfort de polypropylène. L'acier utilisé est un acier galvanisé DP 500 d'épaisseur 0.5 mm traitée chimiquement par une solution à base d'acide hexafluorotitanique. Afin d'optimiser les systèmes, on a étudié l'influence du traitement de surface (composition, nature, etc) sur l'adhésion avant et après vieillissement humide. L'objectif est de maitriser les paramètres prépondérants sur les niveaux d'adhérence, le mode de rupture et les mécanismes de délamination / The aim of this work is to develop a thick steel / polymer composite for weight savings in automotive industry. Formability, dent and corrosion resistance, damping behaviour, impact resistance (-30°C; + 80°C) could be offered by such materials. A key challenge when developing steel/polymer composite is to ensure a high steel/polymer adhesion level to face material processing (e.g. cutting, forming, ED-paint process) and ageing. The material described in this paper is a two-layer composite consisting of a rigid polymer layer of typically 0.3 mm and one thin Zn coated steel skin of 0.5mm. The metal is treated with a hexafluorotitanic acid based conversion coating (standard solution) and the polymer is a two-layer film displaying: - an adhesive layer (40 μm) of maleic anhydride grafted polypropylene - an reinforced polypropylene copolymer layer (260 μm) The influence of the conversion coating (nature, composition) and the ageing behavior in humid environment in order to optimize the steel/polymer multi-material have been studied in this work

Indiana University-Purdue University Indianapolis (IUPUI) / Statement of problem: Yttria-partially stabilized tetragonal zirconia polycrystal (Y-TZP) all-ceramic restorations have been reported to suffer from chipping or cracking of the veneering porcelain (VP) as the most common complication. There is little information in the literature regarding the influence of surface treatment on VP shear bond strength to Y-TZP after cyclic loading. Purpose of this study: The goals of this study were (1) to investigate the influence of zirconia surface treatments on veneering porcelain shear bond strength and (2) to investigate the influence of cyclic loading on the shear bond strength between VP and Y-TZP. Materials and Methods: 48 cylinder–shaped specimens (6mm in diameter and 4mm in height) were divided into 4 groups containing 12 specimens each according to the surface treatment. As a control group (C), no further treatment was applied to the specimens after grinding. Group H was heat-treated as a pretreatment according to the manufacturer’s recommendations. Group S was airborne-particle abraded with 50 µm alumina (Al2O3) particles under a pressure of 0.4 MPa for 10 seconds. In the group SH, the heat-treatment was performed after the airborne-particle abrasion. A VP cylinder (2.4 mm in diameter and 2 mm in height) was applied and fired on the prepared Y-TZP specimens. The shear bond strength was tested using a universal testing machine. Six specimens from each group were subjected to fatigue (10,000cycles, 1.5Hz, 10N load) before testing. Results: The 3-way ANOVA showed no statistically significant effect of surface treatment and cyclic loading on shear bond strength. The highest mean shear bond strength was recorded for the air-particle abrasion group without cyclic loading (34.1 + 10 MPa). The lowest mean shear bond strength was the air-particle abrasion group with cyclic loading (10.7 ± 15.4 MPa). Sidak multiple comparisons procedure demonstrated cyclic loading specimens had significantly lower shear bond strength than non-cyclic loading specimens after air-particle abrasion without heat treatment (p=0.0126) Conclusion: Within the limitations of this study, (1) Shear bond strength between Y-TZP and VP is not affected statistically by surface treatment using heat treatment, airborne-particle abrasion, and heat treatment after airborne-particle abrasion. (2) There is significant difference in shear bond strength with air-particle abrasion between with and without cyclic loading groups. This difference suggested that air-particle abrasion should be avoided in clinical situations as a surface treatment without heat treatment.

The aim of diploma thesis was preparation of hardened layer on three chosen types of materials with different alloying components content without surface melt by using electron beam technology. The influence of chosen process parameters was observed on the prepared hardened layers properties and shapes. In the first part of bibliographic search there are described electron beam properties, possibilities of his influencing and control. There is given example of complete set of electron beam are mentioned in the second part of theoretical research.

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