This project has as main goal to study the influence of the coating thickness, deposited by arc-PVD- technology, on the Wear resistance of coated cemented carbide inserts in three different turning operations. An additional effort has also been made to develop a new test method for evaluating flank Wear resistance. Three different coating types (Coating A, Coating B and Coating C) have been studied in three distinctive thicknesses (2, 4 and 6 µm) for each type. For two of the coating types (Coating A and B) special studies has been done with the thickest coating, creating two additional coating versions of the thickest coating, by changing various deposition parameters, with the aim to enhance the cohesive properties of the coating and lower the residual stresses at the cutting edge. The results show increased crater Wear resistance with increased coating thickness for all coating types, but the amount of increase changes with coating type (Coating A>B>C).

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and Wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and Wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and Wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and Wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and  the properties of the films, with the Wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and Wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.

Nowadays naval units are participating in international missions, where new and in many cases tougher conditions will affect their propulsion. This essay deals with some of the now developed nanostructure coatings and gives a presentation of how the coatings could function on some exposed parts of the naval powertrain. The essay investigates the possibility that the coatings can be used as a protective layer that will reduce or prevent wear on selected parts of the naval powertrains. As a basis for the essay, nanotechnology is described, as well as different reasons that wear occurs and application techniques for coatings The conclusion is that nanostructured coatings can be applied and provide a much better result on hardness and Wear resistance as of naval powertrains compared to micro-structural coatings, both for manufacturing and renovation. The essay presents a few examples of the military utility of the nanostructure coatings as well as suggestions for further research..

Nowadays naval units are participating in international missions, where new and in many cases tougher conditions will affect their propulsion. This essay deals with some of the now developed nanostructure coatings and gives a presentation of how the coatings could function on some exposed parts of the naval powertrain. The essay investigates the possibility that the coatings can be used as a protective layer that will reduce or prevent wear on selected parts of the naval powertrains. As a basis for the essay, nanotechnology is described, as well as different reasons that wear occurs and application techniques for coatings The conclusion is that nanostructured coatings can be applied and provide a much better result on hardness and Wear resistance as of naval powertrains compared to micro-structural coatings, both for manufacturing and renovation. The essay presents a few examples of the military utility of the nanostructure coatings as well as suggestions for further research..

This review paper summaries scientific research about horse thermoregulation and the consequences of using a blanket. Horse owners put blankets on their horses to protect them when they are clipped, to protect them from bugs, to keep them clean and so on. This can have consequences for the horse which their owners might be unaware of. I have tried to answer following questions by searching the available scientific literature; ? How can the horse maintain thermoregulation? ? Is there a risk of suffering when horses wear a blanket? ? Is there a risk of suffering when horses do not wear a blanket? ? How can animal inspectors estimate the welfare of horses when they wear or do not wear a blanket? My result shows that horses who wear a blanket have an increased risk of becoming overheated, develop a chafing, have an increased exposure hazard and have a restrained natural behaviour.

Volvo Cars in Skövde manufacture and assemble Volvo engines. When attaching the ignition coil to all 4-cylinder engines, a special mounting tool is required. This mounting tool is currently manufactured from injection-molded polyoxymethylene (POM), a thermoplastic. It has been noted that the life span of the tool is shortened as a result of abrasive wear that occurs during the attachment process of the ignition coil.An investigation of the possibility of manufacturing the mounting tool with a 3D-printer is undertaken in cooperation with ÅF, a consultant to Volvo Cars. A literature study is first presented to introduce broader knowledge on the subject.

The purpose of this study is, on the basis of institutional theory, to contribute with moreunderstanding about resistance to management accounting change and also to survey reasonsfor the resistance and how to cope with the resistance.The study is a qualitative case study and semi-structured interviews have been used tocomplement the study?s theoretical area, consisting of scientific articles.The conclusion from the study is that resistance to management accounting change can beunderstood and explained by the institutions of each organisation and its underlying structures. Afurther conclusion is, with the structures in mind there are many reasons for resistance and alsomany ways to cope with the resistance. A model has been produced in purpose to createunderstanding and to survey the resistance to management accounting change..

During this master thesis, wear and friction properties for the high-temperature alloy Kanthal APMT were studied. The results were also compared to 253MA. The initial tests showed, among other things, that the surface fineness of the muffle tubes matters in real applications like conveyor belts. A 253MA-sample wear-tested against a 253MA-tube showed lowest wear at 900°C while a pre-oxidized APMT-sample wear-tested against a APMT-tube had the lowest mean value of the friction force at 1100°C, compared to all other tests..

Aim: The aim of this study was to examine and explain the various methods available to rate the erosion damage, and on which teeth and tooth surfaces of erosion damage mostly occurs in children and adolescents.Method: A literature review was conducted, based on 15 scientific articles that have been reviewed, evaluated and analyzed. Articles were searched for in the database PubMed.Result: Six of the articles used the TWI (tooth wear index), which is an index to diagnose the tooth wear in the primary and permanent dentition. Eight articles used other indices as they considered that the TWI was not sufficiently developed to register the degree of tooth wear on some teeth. Tooth wear in the primary dentition occurs most often in the canines and incisors. Tooth wear in the permanent dentition was found in the literature to be mostly occurring on the occlusal / incisal surfaces of all teeth and tooth surfaces.LyssnaConclusion: There is no common index in the articles but many of them use the TWI.

The agricultural plantingmachines are used just a few weeks every year. That means that the supply of service and spare parts have to be good to make the timeliness costs low at the agricultural hard working periods. The machines wear down successivly when they are used. The wear is harder on some parts than the others on a machine. Spare parts can be dicided into consumables.

This report contains a degree project made by the mechanical engineering students Lennart Andersson and Daniel Jansson. The project has performed in assignment by SOMAS Valves AB in Säffle. SOMAS are leading in development on control and on/off valves. To maintain this position they always want to improve their products. One way in this development is valves that are more tightened.The purpose with our project was to investigate another seat design on a HiCo (High Cobalt Alloy) seat to a SKV 150 PN 25 valve and compare this to an original HiCo seat.By modifying the seat on a ball valve we want to achieve a valve that leaks lesser then a valve whit original seat.

De senaste årens långa och kalla vintrar har lett till ett ökat antal halkolyckor. Genom att undersöka halkolyckors utsträckning samt halkskydd som fanns tillgängliga konstaterades det att ett behov av nya halkskydd fanns. Enkäter för att ge svar på användning av halkskydd togs fram och svar från personer i åldrarna 20-65 visade att man överlag inte använde halkskydd. I stor utsträckning berodde det på halkskyddens dåliga kvalité och den negativa stämpeln som fanns på dem . Textila material undersöktes för att finna lämpliga egenskaper.

The goal with this master thesis has been to evaluate and to examine the stationary resistance bridge. The resistance bridge uses a 4-point measuring to determinate the resistance, which is used in the manufacturing of the conductor. It is then used when the resistance is to be decided for coarser aluminium conductors. A conductor has to fulfil certain demands to be able to move forward in the process. One of these demands is the resistance in ohm/km, which has demands that the measure values of the resistance bridge are as true and precise as possible.