Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 29 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 28-29).

The edge rounding of brittle materials by vibratory finishing, VF, was investigated. Borosilicate glass and silicon nitride specimens were processed in two typical VF setups. In all cases, the processed specimens exhibited wear and chipping at their edges, whereas their flat surfaces remained intact. Edge chipping was strongly affected by the edge geometry and process parameters such as the media size and vibration amplitude of the finisher. Therefore, to achieve smooth chip-less edge, samples were processed in several steps, starting with the least energetic conditions, followed by more energetic ones as the edge became progressively blunter. The analysis of edge wear by VF revealed a new mechanism of wear, not previously reported in the literature. A stochastic numerical model was subsequently developed to model this mechanism of wear. To confirm the validity of the model, the model predictions were compared to the experimental observations of wear in the vibratory finisher. The model was used to investigate the effect of various VF process parameters on the edge wear of brittle materials. A VF simulator was used to investigate wear and chipping under more controlled conditions. The VF simulator launched particles against the specimens at adjustable velocities and impact angles. The effect of particles’ shape, and impact velocity and angle, on the wear of glass edges was investigated. Fundamental differences were observed between wear by abrasive and smooth particles. These differences were attributed to the mechanisms of material removal by abrasive iii and smooth balls. Abrasive balls remove material by the sharp indentation of their surface asperities, whereas smooth particles lack such sharp peaks and hence apply blunt indentation on the edges. To identify the fundamental differences between material removal by sharp and blunt indenters, a series of indentation experiments were carried out on glass edges. Subsequently, these differences were discussed in terms of their implications on wear by abrasive and smooth particles.

The edge rounding of brittle materials by vibratory finishing, VF, was investigated. Borosilicate glass and silicon nitride specimens were processed in two typical VF setups. In all cases, the processed specimens exhibited wear and chipping at their edges, whereas their flat surfaces remained intact. Edge chipping was strongly affected by the edge geometry and process parameters such as the media size and vibration amplitude of the finisher. Therefore, to achieve smooth chip-less edge, samples were processed in several steps, starting with the least energetic conditions, followed by more energetic ones as the edge became progressively blunter. The analysis of edge wear by VF revealed a new mechanism of wear, not previously reported in the literature. A stochastic numerical model was subsequently developed to model this mechanism of wear. To confirm the validity of the model, the model predictions were compared to the experimental observations of wear in the vibratory finisher. The model was used to investigate the effect of various VF process parameters on the edge wear of brittle materials. A VF simulator was used to investigate wear and chipping under more controlled conditions. The VF simulator launched particles against the specimens at adjustable velocities and impact angles. The effect of particles’ shape, and impact velocity and angle, on the wear of glass edges was investigated. Fundamental differences were observed between wear by abrasive and smooth particles. These differences were attributed to the mechanisms of material removal by abrasive iii and smooth balls. Abrasive balls remove material by the sharp indentation of their surface asperities, whereas smooth particles lack such sharp peaks and hence apply blunt indentation on the edges. To identify the fundamental differences between material removal by sharp and blunt indenters, a series of indentation experiments were carried out on glass edges. Subsequently, these differences were discussed in terms of their implications on wear by abrasive and smooth particles.

Des de principis dels anys seixanta, els materials coneguts com a vidres metàl·lics han estat objecte d’un gran número d’investigacions centrades principalment en la comprensió de la seva estructura i de les propietats tèrmiques, magnètiques i mecàniques. Tal com el seu nom indica, sent vidres no presenten ordenament atòmic a llarg abast donant lloc a la seva estructura amorfa. Aquesta falta d’ordre els confereix propietats i comportaments considerablement diferents respecte als aliatges cristal·lins. En el camp de les propietats mecàniques, els vidres metàl·lics es caracteritzen per posseir un alt límit elàstic que, juntament amb la possibilitat d’obtenir-los en forma màssica, ha obert un nou camp d’interès en la utilització d’aquests com a materials estructurals. No obstant, la deformació plàstica a temperatura ambient succeeix de forma molt localitzada mitjançant la formació de bandes de cisalla. Com a conseqüència, els vidres metàl·lics, enlloc d’experimentar enduriment per deformació típica dels materials cristal·lins, s’ablaneixen impedint una deformació plàstica estable. Com a resultat, malgrat el seu alt límit de fluència, els vidres metàl·lics tendeixen a fracturar-se després d’una deformació macroscòpica limitada, restringint d’aquesta manera la seva utilització en molts camps d’aplicació. Així doncs, en els darrers temps, la millora de la plasticitat d’aquest tipus de materials s’ha convertit en l’objecte de molts treballs d’investigació. Apart d’alguns casos puntuals on s’han trobat vidres metàl·lics amb plasticitat intrínseca, el concepte més explorat per tal d’evitar tal ruptura catastròfica ha estat la precipitació d’una segona fase. Vàries rutes han estat provades per obtenir aliatges amb matriu amorfa amb més ductilitat: afegir directament una fase reforçant al material fos, dissenyar una composició adequada que resulti en un material compost al solidificar-lo o precipitar la segona fase durant un tractament tèrmic o de deformació. Seguint una d’aquestes rutes, un aliatge heterogeni format, ja sigui per una fase cristal·lina micro- o nano-mètrica, una fase quasicristal·lina o fins i tot una segona fase amorfa integrada dins una matriu amorfa ha estat fabricat. L’estudi desenvolupat al llarg d’aquesta Tesi es centra bàsicament en la millora de les propietats mecàniques dels vidres metàl·lics, donant especial èmfasi a la millora de la plasticitat, mitjançant algunes de les tècniques esmentades anteriorment. Principalment, s’han estudiat els canvis estructurals induïts per deformació, tractament tèrmic i afegint un nou element en diferents famílies de vidres metàl·lics i l’efecte de tals en les propietats mecàniques resultants. Els canvis estructurals han estat caracteritzats per tècniques de calorimetria, difracció de raig-X i per microscòpia electrònica. Tot seguit, la influència d’aquests en el comportament mecànic dels vidres s’ha portat a terme mitjançant principalment tests de compressió i nanoindentació. Els canvis mecànics i estructurals ocasionats per tractaments tèrmics en dues famílies de vidres metàl·lics (basats en Ti i en Fe) han estat estudiats. D’aquesta secció podríem concloure que bé si s’ha observat una bona millora en les propietats mecàniques (mòdul de Young, duresa, resistència al desgast,etc) quan el tractament tèrmic s’ha dut a terme al voltant de la temperatura de transició vítria (microstructura formada per nanocristalls dispersos en una matriu amorfa) la plasticitat continua sent limitada. Tot seguit, hem estudiat els canvis ocasionats per l’addició d’un element, Nb, en una composició inicialment amorfa. Hem pogut observar, com a mesura que introduïm Nb a l’aliatge format per Ti, Zr, Cu i Pd la capacitat de formació vítria va disminuint fins que per un percentatge de Nb del 4 % atòmic ens trobem amb un aliatge pràcticament cristal·lí. No obstant, en les composicions amb el 2% i el 3% de Nb, on s’observa una microstructura formada per petits cristalls integrats en una matriu amorfa, s’ha observat un increment notable (al voltant del 10%) en la plasticitat de l’aliatge. Aquesta Tesi també engloba un estudi detallat de la resposta de materials inicialment amorfs al ser sotmesos a diferents nivells de deformació plàstica. Tot i ser sotmesos a les mateixes condicions de deformació, en l’aliatge basat en titani es detecta ablaniment, mentre que en l’aliatge format principalment per zirconi s’observa enduriment. Els possibles efectes d’aquest comportament dissimilar són explicats en termes de volum lliure, cristal·lització i canvis en l’ordre a curt abast. / Metallic glasses have been the subject of widespread research since the 1960's with significant progress in the understanding of their behaviour. They are amorphous metallic alloys; as the name suggests, being glasses, they do not possess long range order because of their amorphous nature; formed by metals, they are not transparent to light. As a result, they exhibit unique chemical, physical, mechanical and magnetic properties compared to conventional crystalline metallic alloys. In particular, their high yield strength together with the possibility of casting them into bulk form has triggered the interest in using them as structural materials. However, plastic deformation at room temperature occurs in a highly localized manner by the formation of a few shear bands. Instead of work hardening, metallic glasses soften upon deformation, which prevents stable plastic elongation. Once yielding has set in, most metallic glasses tend to fracture in a brittle manner, with almost total lack of plasticity, restricting their use in many applications. As expected, in the last decade, many works were focused on the circumvention of this limited plasticity. Apart from some specific cases where intrinsic plasticity was observed, precipitation of a second phase was found to be the most effective way to promote multiple shear band formation and obtain both, high strength and enhanced plasticity. Many methods were developed to achieve such heterogeneous microstructure. For instance, the second phase can be physically added to the alloy prior to casting, precipitated directly from the melt or by thermal or mechanical treatments of the as-cast alloy. Following one of those procedures a microstructure composed of either a micro- or nano- sized crystalline, quasi-crystalline or non-crystalline phases embedded in an amorphous matrix can be synthesized. The structural and mechanical changes induced in metallic glasses by annealing, element addition and deformation form the main topic of the work presented in this Thesis. The microstructural changes have been characterized by calorimetry, X-ray diffraction and electron microscopy. The influence of these changes on the mechanical behaviour of these glasses has been mainly investigated through compression tests and nanoindentation tests. Structural and mechanical changes upon annealing have been studied in two families of metallic glasses: a Ti40Zr10Cu38Pd12 alloy and a Fe36Co36B19.2Si4.8Nb4 alloy. Annealing treatments of these alloys around Tg, when disperse nanacrystallites are embedded in an amorphous matrix, results in enhanced mechanical properties. However, the former is believed to deteriorate plasticity due to structural relaxation of the amorphous structure. On the other hand, the appearance of tiny nanocrystals embedded in an amorphous matrix is found to be the responsible of the increase above 10% of plastic strain when 3 % of Nb is added to the amorphous Ti40Zr10Cu38Pd12 alloy. However, a brittle behaviour is observed if the Nb content is exceedingly high (4%). The structural and mechanical changes experienced by metallic glasses upon deformation treatments have also been subject of study in this thesis. While strain softening in the Ti40Zr25Ni8Cu9Be18 metallic glass alloy takes place as deformation proceeds (by means of compression test as well as during nanoindentation), in the Zr62Cu18Ni10Al10 BMG the opposite effect, strain hardening, is observed. The possible reasons of the observed dissimilar behaviour have been explained in terms of free volume, crystallization and changes in the short range order.

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Resurssnål produktion är en teori om hur produktionsplanering i ett företag kan förbättras, vilket syftar till att öka effektiviteten och skapa en bättre arbetssituation för medarbetarna i företaget. Examensarbetets övergripande syfte har varit att med stöd i denna teori ta fram ett optimerat och verklighetstroget truckkörschema för dagens interna transporter vid Emhart Glass i Sundsvall. Målsättningen har varit att jämföra de interna transporterna med de behov som finns i företaget, att identifiera hur ofta transporter av tomma lastpallar sker samt att klar-göra om en dubbelpallshantering innebär tidsmässigt vinst. En kart-läggning av de interna transporterna och arbetsställenas behov av lastpallar har genomförts. Informationen från kartläggningen har implementerats i programmet Matlab, där en algoritm för beräkning av ett körschema har skapats som tar hänsyn till dagens tidshantering av lastpallar och sannolikheten att truckförarna lastar av och på lastpallar vid olika arbetsställen. Jämförelsen av arbetsställenas behov och truck-körningarna visar att behoven vid arbetsställena och dagens truckkör-ning stämmer ganska bra överens. Med stöd av kartläggningen har ett truckschema kunnat konstrueras för enkelpallshantering samt för dubbelpallshantering. Körschemana visar att det finns möjligheter till optimering av de interna transporterna. Den viktigaste slutsatsen har varit att kunna visa att truckförarnas trucktransporter kan både fören-klas och effektiviseras genom ett körschema, och det i sin tur kan leda till att arbetssituationen blir mer effektiv och mindre stressig.

This degree project was made in cooperation with AssiDomän Frövi and Charlotte Andersson and the main objectivehas been to create to ice cream pacbges from 250 gsm Frövi Light board. The paekages are intended to be easilyresealable while decreasing in size together with the ice cream. The project also describes the food packaging labelsand symbols currently present in the European common market.Both capsules utilize a separate lid for resealing. One of the paekages (Capsuie A) is indended to be cut along withthe ice cream and thereby decrease in size. The other one (Capsuie B) uses a series of flaps for contracting and expandingwhich enab1es adjusting of the size without cutting the package up.The design for Capsuie A is created both as a series of flavours with a super-hero theme intended for children andwith a colfee flavour for a maturer audience. For Capsule B, a design was created for a sorbet.

The optical properties of transparent chromium-doped glass-ceramics with the chemical composition similar to that of cunyite (Cr 4+ :Ca 2 GeO 4 ) crystal were investigated. Room temperature absorption, DTA, XRD as well as fluorescence were measured. Parent (as quenched) glass does not exhibit any fluorescence; after the heat treatment Cr 4+ fluorescence band appears at 1280 nm, very similar to the emission of Cr 4+ :Ca 2 GeO 4 bulk crystals. Optical properties of nanocrystals formed in the glass-ceramics. The size of crystallites is below 600nm. glass-ceramics we concluded that the nanocrystal phase is a modified Ca 2 GeO 4 structure. In order to increase the fluorescence and synthesis more small crystals, we doped TiO 2 and ZrO 2 as nucleating agents, glass does not exhibit any fluorescence when glass-ceramics does not heat treatment ; after the heat treatment Cr 4+ fluorescence band appears at 1280 nm too. The crystals formed in glass media after heat-treatment have spherulitic shape with the size up to 300-500nm, and there are more nanocrystals distribute the surface, especially doped TiO 2 we found the more smaller crystals in it. We expect that crystallites with the size below 100 nm may be formed by adjustment of initial glass composition with nucleating agents and optimization of heat-treatment procedure parameters.

The tensile behavior of the monolithic amorphous ZrCu and crystalline Cu thin films and the ZrCu/Cu multilayered thin films, coated on polyimide (PI) substrates in different layer thicknesses has been investigated. The scanning electron microscope (SEM) morphology of the as-deposited thin film is composed of sphere domains. Between the domains, stress concentration is induced. The cracks perpendicular to the loading direction would propagate along the domains. The constituent component examined by energy dispersive X-ray spectrometer (EDS) shows that the average composition (in atomic percent) amorphous thin film is Zr46.78Cu53.22, closed to the designed Zr50Cu50 goal. The X-ray diffraction (XRD) results show that the multilayered specimens are composed of both amorphous ZrCu and nanocrystalline Cu crystal structure. As the monolayer thickness become lower, the normalized peak height and grain sizes of Cu become lower. To obtain the mechanical properties of the coated films, deducting the contribution of substrates is used in this study. The tensile Young¡¦s moduli of monolithic amorphous ZrCu and nanocrystalline Cu thin films are close to the results extracted from micro-compression. Based on the current tensile results for the moduli of multilayered thin films, the obtained mechanical data are demonstrated to be reliable and are consistent with the theoretical values predicted by Rule of Mixture. As the thickness decreases from 100 nm down to 10 nm, the tensile Young¡¦s moduli do not vary much. On the other hand, the maximum tensile stress shows strong variation, being highest for the layer thickness of 25 nm. The deformed surface morphologies characterized by scanning electron microscopy also exhibit a similar trend. The optimum tensile properties of the monolithic and multilayered thin film combinations are examined and discussed in this thesis.

This thesis mainly studying the impact of TiO2 and K2O these two compounds in the Chromium-doped glasses and glass-ceramics. Due to the method of Modified Chemical Vapor Deposition (MCVD) of Chromium-doped fiber preform production process, the Ti and K elements have some difficulties; thus, we discuss the influences of these two elements. We hope to improve the composition after knowing these two elements, in order to make the Chromium-doped fiber preform well. We change the weight percent of TiO2 and K2O in the glass composition, in order to observe the influences. Then, we measure their optical and material properties. The results of experiments show that the well-known nucleation agent: TiO2, have no effect of the crystalline phase. However, its function is to help the formation of crystals. We can conclude by the results of X-ray Diffraction (XRD). K2O plays an important role of the Mg2SiO4 phase. To add K2O or not, is the most important reason to affect the Mg2SiO4 phase formation. We will discuss in detail in this thesis about the phase difference for the fluorescence characteristics of Chromium-doped glass and glass-ceramics. What¡¦s more, we use the previously developed two times laser heat-treatment, hoping to successfully apply for Chromium-doped fiber drawing in the future. The laser heat-treatment of CO2-laser can induce the crystal in the glasses. However, this method only needs just a few seconds, which can reduce the cost of heat-treatment. In addition, we can reduce the crystalline size by using the method of two times laser heat-treatment, which can decrease the scattering loss. Also, we will discuss the impact of laser heat-treatment after changing the composition.