The thesis deals with a draft production procedure for a specific welded component of a bearing console, including the consideration of the basic material welding quality, the selection of welding method and parameters, thermal processing, if applicable, and the selection of filler material. Draft welding procedure of WPS and weld check. Consideration of the use of a robot.

Le caoutchouc naturel (NR pour Natural Rubber) est une matière première indispensable à la fabrication de milliers de produits !Le choix du latex naturel tient principalement à ses propriétés physico-chimiques intrinsèques bien supérieures à celles des latex synthétiques. Industriellement, le NR est cependant rarement utilisé seul mais associé à des particules de renfort, appelées charges, pour former un matériau composite aux propriétés mécaniques grandement améliorées en particulier la résistance à l’usure.Des études récentes ont mis en évidence que la méthode conventionnelle consistant à introduire les charges sous forme de poudres fines au sein d’un bloc de NR solide ou fondu n’est pas la plus efficace. Une nouvelle approche consistant à mélanger les deux entités, NR et charges, en phase liquide avant séchage s’annonce prometteuse industriellement, mais la littérature à ce sujet est encore très limitée. Ce travail de thèse a visé à parfaire la compréhension des processus gouvernant les interactions NR-charges renforçantes en phase liquide. Pour ce faire nous avons (i) décrit les propriétés physico-chimiques de surface des particules NR en phase liquide, (ii) étudier les effets de la charge renforçante (en termes de taille, composition, fonctionnalisation de surface, concentration) et de la solution (ions valence) sur l'interaction NR-charge et (iii) quantifier les propriétés mécaniques des particules NR.Nous avons été en mesure d’identifier les paramètres clés qui permettent en phase aqueuse diluée, non seulement d’influencer l’interaction particule de NR-charge mais aussi de réguler la dynamique d'interaction et de contrôler la structure des hétéro-agrégats formés.Cette approche originale de l’hétérocoagulation NR-charge en phase liquide ouvre de nombreuses perspectives en vue d’améliorer les propriétés des matériaux composites NR-particules de renfort. / Natural rubber (NR) is an indispensable raw material used in the manufacturing of more than 40,000 products primarily due to its excellent intrinsic physical properties. However, NR is seldom used in its raw state. Often, it needs to be reinforced with particulate fillers (nanoparticles) to further improve its physical strength required for most applications. The precise origin of this mechanical reinforcement effect remains unclear, however, optimal reinforcements appears to depend on the dispersion of filler in the NR matrix and the interaction of NR and filler.It was found that the conventional method of pouring fine powders in a solid block of rubber/melt is not the most efficient way to disperse the fillers. The new alternative approach in which the two components are first dispersed in liquid has shown promising results but available literature is still very limited. Furthermore, the microscopic mechanism involved in the interaction of NR and filler in liquid is still unknown. In this context, we (i) described the physico-chemical surface properties of NR particles in liquid, (ii) identified key filler (size, composition, surface activity, concentration) and solution (ion valence) related parameters to comprehend the structural, morphological, and dynamical evolution of the NR-filler interaction, and (iii) quantified the mechanical properties of the NR particles. With this approach we were able to provide the first reports on the physical processes involved in the interaction of NR and filler. More importantly, a recipe for the basic yet crucial parameters that controls and modulates NR-filler heteroaggregation was established. This could open the way to further understand the reinforcement effect.

The erosion or dissolution of stainless steel grade 304 as base metal by molten brazing fillermetal was investigated using one nickel and two iron based filler metals. The difference betweentwo iron filler metal is 5 % Manganese content in one of the filler metal. The Wettability of fillermetal is effected by oxidation of base or filler metal for which high vacuum or non reacting gasis used as a furnace atmosphere to reduce the partial pressure of oxygen. The furnace parameterseffecting erosion of base metal was observed e.g. peak temperature and brazing time. The effectof filler mass was also observed. The erosion depth was measured by light optical microscope.All the three filler metal shows different erosion behavior in nitrogen atmosphere compare tohigh vacuum. In high vacuum some of the elements evaporates at brazing temperature whichchanges the properties of filler metal. This change of composition in filler metal was observed byEDX analysis. SEM analysis was used to identify different element rich phases.

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Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 170-176).

Nowadays, when environmental concerns are becoming increasingly important are there great interest in natural materials and recyclability. The possibility of reusing materials with maintained mechanical properties are essential for sustainability. Today produced approximately 90,000 tons of natural fiber reinforced composites in Europe of those are 40,000 tons compression molded of which the automotive industry uses 95%. Natural fiber reinforced composites is recyclable and therefore interesting in many applications. Also, natural fiber reinforced composites is inexpensive, light in weight and shows decent mechanical properties which makes them attractive to manufactures. However, the problem with natural fiber reinforced composites is the poor adhesion between fiber and matrix, the sensitivity of humidity and their low thermal stability. Those problems could be overcome by addition of compatibilizer and reactive filler. This study will examine the technical requirement in order to develop a sustainable and recyclable biocomposite. It investigates the composition of matrix (polypropylene), fiber (flax), compatibilizer (maleic anhydride grafted polypropylene) and reactive filler (CaO) in order to obtain various combinations of stiffness, strength and processability. The two main methods used for preparing samples were compounding and injection molding. Results shows that 20 wt% flax was the optimal fiber content and that maleic anhydride grafted polypropylene is a very good compatibilizer by enhancing the strength significant. Surprisingly was the strength impaired due to the addition of CaO. The composition of 20 wt% flax, 1 wt% maleic anhydride grafted polypropylene and 79 wt% polypropylene is the technically most favorable composition.

The current generation of Glass Ionomer Cements (GICs) have many advantageous properties over other dental restorative materials but lack the compressive strength of these other materials. The aim of this project is to increase the compressive strength of conventional Glass Poly-Vinyl-Phosphonate cement by inclusion of reactive sub-micron filler particles. The setting characteristics, chemical reactivity and cement strength have been found using oscillating rheology, infrared spectrometry, nuclear magnetic spectrometry, transmission electron microscopy, potentiometer analysis, laser diffractometry and mechanical analysis. The addition of sub-micron filler particles in direct weight by weight replacement of aluminosilicate glass of a control material has increased the ultimate compressive strength of the new cement from 206MPa (control) to 250MPa after 365 days of aging. The strength of the new filler enhanced cements were comparable with the control material after 3 hours. The setting chemistry of the filler enhanced cements follows the same order as the control cement but at a decelerated rate. Theoretical modelling found that a large volume of sub-micron filler could fit into interstitial spacing in formed cement however the alteration of the aluminosilicate glass to polyelectrolyte ratio has been found to drastically alter the cement setting time. The use of cubic and polyhedral shaped filler particles as supposed to spherical particles may increase the cement strength further as greater packing densities are achieved. The formulation of a Glass Ionomer Cement with increased compressive strength may find use as a posterior restorative or as a better material for restoration of lesions and cavity liners.

De par leur présence à l’interface entre plusieurs domaines linguistiques (phonologie, morpho-syntaxe, sémantique ou pragmatique), les déterminants ont depuis longtemps suscité l’intérêt des chercheurs en acquisition. On trouve ainsi de nombreux travaux portant notamment sur les contraintes phono-prosodiques, lexico-syntaxiques, sémantiques ou pragmatiques à l’œuvre dans le processus d’acquisition de ces formes, mais peu d’entre eux ont cherché à proposer une analyse combinée de ces facteurs, en tenant compte à la fois des morphèmes adultes et des formes de transition (omissions et fillers). Nous avons donc souhaité, dans le cadre de ce travail, décrire l’émergence des déterminants et de leurs proto-formes en essayant de saisir, dans une perspective multidimensionnelle intégrant à la fois des facteurs distributionnels et fonctionnels, quels facteurs influencent le plus ce processus, et à quelles périodes.Cette thèse repose sur l’analyse d’un corpus longitudinal de quatre enfants, âgés de 1;6 pour le plus jeune lors de la première séance sélectionnée à 3;5 pour le plus âgé lors de la dernière. Nous avons repéré au sein de ce corpus tous les noms produits par les enfants ainsi que les formes les précédant et chaque syntagme a fait l’objet d’une analyse phono-prosodique, lexico-syntaxique, sémantique, pragmatique et discursive.Les résultats montrent d’une part que tous les facteurs distributionnels peuvent - à des degrés différents - influencer la production des formes pré-nominales, et d’autre part, que les usages que les enfants font des formes témoignent d’une sensibilité précoce à certains contrastes pragmatico-discursifs. Toutefois, aucun des facteurs pris séparément n’a permis de rendre compte de l’intégralité des productions des enfants. L’analyse conjointe de ces facteurs distributionnels et fonctionnels a confirmé les tendances dégagées au préalable et a mis en évidence l’influence d’un ensemble de facteurs (et en particulier, phono-prosodique, syntaxique et pragmatique) plus que d’un facteur unique ou prédominant tout au long du processus d’acquisition des déterminants. / Given their presence at the crossroads of different linguistic fields (phonology, morphosyntax, semantics or pragmatics), determiners have for a long time aroused the interest of language acquisition researchers. We thus find several studies dealing with the phono-prosodic, lexical and syntactic, semantic or pragmatic constraints involved in the acquisition of determiners. But only few of them have provided a combined analysis of all these factors, considering both adult morphemes and transitional forms (omissions and filler syllables). Our study aims to describe the emergence of filler syllables and determiners and understand - in a multidimensional perspective examining simultaneously distributional and functional factors - which factors may affect the acquisition process, and over which periods of time.Our study is based on a corpus of four children, aged from 1;6 for the youngest in the first selected session to 3;5 for the eldest in the last session. We first identified all the noun phrases produced in the data and each occurrence was then analysed according to phono-prosodic, lexical, syntactic, semantic, pragmatic and discursive factors.Our results show that each distributional factor may influence, at different degrees, the production of pre-nominal forms and that children’s use of forms shows early sensitivity to pragmatic factors. However, none of the factors taken separately have accounted for all of the children’s productions. An additional combined analysis of both distributional and functional factors has supported the initial trends and highlighted the influence of a series of factors (and in particular, phono-prosodic, syntactic and pragmatic), more than a single and predominant one throughout the acquisition process of determiners.