Magnesium with two-thirds of the density compared to aluminium and one-quarter of steel, intrigues product developers and material scientists due to the light metal’s excellent combination of strength to weight ratio as well as their capability of being produced as a High Pressure Die Cast component compared to other ferrous or light metal alloys.   However, a magnesium alloy inherits some concerning drawbacks, limiting the exploitation in structural applications and mechanical design such as automotive, heavy machinery and aerospace components. The need for a magnesium alloy that could withstand a sufficient amount of wear, temperature and corrosive environment, leads towards the investigation and evaluation of a suitable, functional coating as a solution to exploit the evident advantages a magnesium alloy exhibits. A substantial amount of research is required in order to reduce an existing knowledge gap that is the ongoing development in the search for a sufficient functional coating and adherence capability to the highly reactive substrate that is a magnesium alloy.   This industrial master thesis is an early stage investigation to evaluate how the currently used aluminium substrate with an electrodeposited coating relate and compares to a heat-treated electroless deposited coating through tribological and thermophysical induced stresses. These properties are tested with proven industrial standard methods resulted in a comprehensive conclusion and discussion regarding the feasibility of applying the coating onto a commercial magnesium alloy closely related to the Mg-alloy developed by Husqvarna and thereby contributing to technological advances to the highly relevant topic within product development in materials engineering.

High-performance materials such as stainless steels and nickel based super alloys are widely used in demanding applications where high mechanical and thermal properties are required. The applications of super alloys are mainly found in jet engines, power plants and gas turbines demanding high fatigue strength, corrosion and oxidation resistance as well as wear resistant properties. In order to use them, they go through various machining processes such as milling, turning, cutting, polishing etc. until the final product is achieved. Modern manufacturing industries employs various machining tools and technologies to improve the machining process of heat resistant super alloys. However, there are still challenges which needs to be addressed. Among them, adhesive wear of the machining tools is one of the main wear mechanism during the tribological interaction of tool and workpiece, preventing them to achieve the desired quality and surface finish of the end product. Moreover, it damages the tool reducing its lifecycle and in return, increasing the production cost. Among the cutting tools tungsten carbide (WC/Co) tools coated with TiAlN coating due to their good high temperature performance are extensively used. Nonetheless, these coatings still face issue like adhesive wear, abrasion, oxidation at higher temperature damaging the tools and subsequent machining. Therefore, it is imperative to understand the initiation mechanism of adhesive wear during the tribological interaction of super alloys and coated cutting tool material. In this research work, the tribological response of two coatings deposited by physical vapour deposition (PVD), having the composition Ti60Al40N and Ti40Al60N have been studied against two super alloys material, i.e. Inconel 718 and stainless steel 316L. A high temperature SRV (Schwingung (Oscillating), Reibung (Friction), Verschleiß (Wear)) reciprocation friction and wear test set up was employed to investigate the friction behaviour, wear rate and dominant wear mechanisms.  For Ti60Al40N coating, the experimental results revealed that generally, friction increases in case of sliding against Inconel 718 up to 400 °C and drops at 760 °C. A high wear volume at room temperature and a decrease to a minimum at 760 °C has been observed for Inconel 718. On the other side, Stainless steel 316L (SS 316L) faces a continuous rise in friction coefficient with highest value at 760 °C during sliding against Ti60Al40N coating. Wear is highest at 400 °C for SS 316L pin. The worn surfaces shows that both workpiece materials experience increase in material transfer due to adhesive wear with rise in temperature. At 400 °C, adhesion is the primary wear mechanism for both workpiece materials. A further rise in temperature to 760 °C promotes the adhesive wear through oxides formation on both material surfaces.  Similarly, Ti40Al60N coating shows the same friction behaviour with change in average steady state friction values for both material of Inconel 718 and SS 316L. Both workpiece materials responds in a similar way to wear volume loss, i.e. lowest at room temperature and highest at 760 °C. For Inconel 718, transfer of coating constituents on to the Inconel 718 pin surface was detected and associated with coating rupture and peeling, exacerbating with rise in temperature. Adhesion, abrasion, and oxidation are primary wear mechanisms at 400 °C and 760 °C. For SS 316L, coating transfer only happen at 400 °C. No damage of coating at 40 °C, a complete damage at 400 °C, and formation of dense porous oxides layers at 760 °C have been noticed. At 400 °C, adhesion, abrasion, and chipping while at 760 °C, adhesion, three body abrasion, ploughing and oxidation are the main wear mechanisms.

This Master's thesis is part of the Hydrogen Embrittlement in Rolling element bearings project (HERo) initiated at Luleå University of Technology (LTU), with the primary objective of determining critical hydrogen concentrations in bearing steel for rolling element bearings. The specific aim of this Master's thesis is to design a test rig that enables the investigation of the effects of hydrogen embrittlement on rolling element bearings under load. The design process focused on ease of manufacture and assembly. The developed test rig includes an electric motor, a pneumatic load application mechanism, and an electrochemical cell. Using the leverage principle, a thrust roller bearing is loaded vertically, while it is driven by an electric motor that is connected to the bearing with a tyre coupling. The electrochemical cell, which consists of a reference electrode, counter electrode, and the test bearing as the working electrode, is used to charge the test bearing with hydrogen. The cell was designed to be easily accessible between tests to facilitate the change of thrust roller bearings. The test bench enables the analysis of rolling element bearings that are exposed to simultaneous hydrogen embrittlement and realistic operating conditions. / Detta examensarbete är en del av Hydrogen Embrittlement in Rolling element bearings-projektet (HERo) som pågår vid Luleå tekniska universitet (LTU), med huvudmålet att bestämma de kritiska vätekoncentrationerna i lagerstål för rullningslager. Det specifika målet med detta examensarbete är att konstruera en testrigg för att direkt undersöka effekten av väteförsprödning av lager i en simulerad verklig tillämpning. Designprocessen fokuserade på enkel tillverkning och montering.  Den utvecklade testriggen inkluderar en elmotor, en pneumatisk lastpåläggnings-mekanism och en elektrokemisk cell. Med hjälp av hävstångsprincipen belastas ett axiellt rullager vertikalt, medan det drivs av en elmotor via en däckkoppling. Den elektrokemiska cellen, som består av en referenselektrod, motelektrod och testlagret som arbetselektrod, används för att införa väte i lagret. Cellen har konstruerats på ett sätt som underlättar byte av testlager mellan testerna.  Testriggen skapar därmed möjligheten att analysera rullningslager som utsätts för väteförsprödning under realistiska driftförhållanden. / Diese Masterarbeit ist Teil des Hydrogen Embrittlement in Rolling element bearings-Projekts (HERo), das an der Technischen Universität Luleå (LTU) initiiert wurde, mit dem primären Ziel, kritische Wasserstoffkonzentrationen für Lageranwendungen zu bestimmen. Das spezifische Ziel dieser Masterarbeit ist es, einen Prüfstand zu konstruieren, um die Auswirkungen von Wasserstoffversprödung auf Rollenlager im Belastungszustand zu untersuchen. Der Schwerpunkt des Designprozesses lag darauf, eine einfache Fertigung und Montage des Prüfstandes zu gewährleisten.  Der entwickelte Prüfstand umfasst einen Motor, einen Mechanismus zur Lastaufbringung und eine elektrochemische Zelle. Mithilfe des Hebelgesetzes wird das Testlager vertikal belastet, während es mithilfe eines Elektromotors und einer Reifenkupplung angetrieben wird. Die elektrochemische Zelle, bestehend aus Referenzelektrode, Gegenelektrode, und dem Testlager als Arbeitselektrode, dient dazu, Wasserstoff in das Testlager einzubringen. In ihrem Design wurde darauf geachtet, dass sie zwischen den Tests leicht zugänglich ist, um den Austausch der Testproben zu erleichtern. Der Prüfstand ermöglicht somit die Analyse von Rollenlagern, die sowohl Wasserstoffversprödung als auch realistischen Betriebsbedingungen ausgesetzt sind.

Today, lead is used in various engineering applications due to its desirable tribological properties. However, the negative health and environmental impacts associated with lead have raised concerns and resulted in regulatory restrictions on its use. It is therefore nessessary to fnd lead-free materials that can provide similar or even better performance than the commonly used lead-containing alloys. Scania, currently uses leaded alloys for a number of gearbox components where sliding wear can be an issue. This study aims to evaluate the tribological properties of fve lead-free alternative materials and assess their suitability as replacement for the currently used material, Leaded Brass. The tests were conducted in a pin-on-disk setup under similar conditions of those found in Scania’s gearbox. The results showed that the friction and wear was similar between Copper Beryllium and Leaded Brass, which indicates that Copper Beryllium is a potential replacement. Additionally, Nedox and Aluminum Bronze (APS) demonstrated signifcantly superior wear resistance, exhibiting 97% less wear compared to Leaded Brass while maintaining similar friction levels. These results underscore the potential for implementing lead-free materials to enhance sustainability and performance in critical applications like gearbox components. / Idag används bly i olika tekniska tillämpningar på grund av dess önskvärda tribologiska egenskaper. Men de negativa hälso- och miljöeffekterna associerade med bly har väckt oro och resulterat i reglerande begränsningar för dess användning. Det är därför nödvändigt att hitta blyfria material som kan erbjuda liknande eller till och med bättre prestanda än de vanligt förekommande blyhaltiga legeringarna. Scania använder för närvarande blyhaltiga legeringar för ett antal växellådskomponenter där glidande slitage kan vara ett problem. Denna studie syftar till att utvärdera de tribologiska egenskaperna hos fem blyfria alternativa material och bedöma deras lämplighet som ersättning för det nuvarande materialet, blyhaltig mässing. Testerna utfördes i en pin-on-disk konfiguration under liknande förhållanden som de som återfinns i Scanias växellåda. Resultaten visade att friktionen och slitage var liknande mellan kopparberyllium och blyhaltig mässing, vilket tyder på att kopparberyllium är en potentiell ersättare. Dessutom visade Nedox och aluminiumbrons (APS) betydligt överlägsen slitagebeständighet, med 97% mindre slitage jämfört med blyhaltig mässing, samtidigt som båda materialen hade liknande friktionsnivåer. Dessa resultat visar potentialen som finns med att implementera blyfria material för att förbättra hållbarheten och prestandan i kritiska tillämpningar som växellådskomponenter. / Heutzutage wird Blei aufgrund seiner wünschenswerten tribologischen Eigenschaften in verschiedenen technischen Anwendungen verwendet. Jedoch haben die negativen gesundheitlichen und Umweltauswirkungen, die mit Blei verbunden sind, Bedenken hervorgerufen und zu regulatorischen Beschränkungen seiner Verwendung geführt. Daher ist es notwendig, bleifreie Materialien zu finden, die ähnliche oder sogar bessere Leistungen als die üblicherweise verwendeten bleihaltigen Legierungen bieten können. Scania verwendet derzeit bleihaltige Legierungen für eine Reihe von Getriebekomponenten, bei denen Gleitverschleiß auftreten kann. Das Ziel dieser Studie ist es, die tribologischen Eigenschaften von fünf bleifreien Alternativmaterialien zu bewerten und ihre Eignung als Ersatz für das derzeit verwendete Material, Bleihaltiges Messing, zu prüfen. Die Tests wurden in einem Pin-on-Disk-Aufbau unter ähnlichen Bedingungen wie in den Getrieben von Scania durchgeführt. Die Ergebnisse zeigten, dass Reibung und Verschleiß zwischen Kupferberyllium und Bleihaltigem Messing ähnlich waren, was darauf hinweist, dass Kupferberyllium ein potenzieller Ersatz sein könnte. Darüber hinaus wiesen Nedox und Aluminiumbronze (APS) eine signifikant überlegene Verschleißfestigkeit auf und zeigten 97 % weniger Verschleiß im Vergleich zu Bleihaltigem Messing bei gleichbleibendem Reibungsniveau. Diese Ergebnisse unterstreichen das Potenzial zur Implementierung von bleifreien Materialien, um die Nachhaltigkeit und Leistungsfähigkeit in kritischen Anwendungen wie Getriebekomponenten zu verbessern.

Materialet i rapporten är 10% av det totala materialet som presenterats till SCA, de viktigaste resultaten redovisas i rapporten. Vid SCA:s sågverk Rundvik i Nordmaling finns en automatiserad emballeringsmaskin. Ingen bra anvisning för bruk/drift och underhåll för maskinen finns, vilket har gjort det svårt för personalen att hantera den. Syftet med detta arbete var att kartlägga maskinens delar, funktioner och därefter framta en bruksanvisning. Detta gjordes genom att först kartlägga placeringen av maskinens axlar samt dess funktioner. Därefter intervjuades personalen på hyvleriet för att reda ut svårigheter och problem med maskinen. En problemlösning som löser de mest förekommande felen har framställts. En underhållsplan har tagits fram för att underlätta underhåll av maskinen. En offert på en programuppdatering har skickats till maskinprogrammerare. En offert gällande en säkerhetsanordning till maskinen har skickats till maskintillverkare. Resultatet är en fullt användbar, enkelt läsbar bruksanvisning. Syftet har inte fullföljts helt då operatör inte hunnit testa instruktionerna. / The material in the report is 10% of the total material presented to SCA, the most important results are reported here. At SCA's sawmill Rundvik in Nordmaling, there is an automated packaging machine. There is no good user manual for use/operation and maintenance of the machine, which has made it difficult for the staff to handle it. The purpose of this work has been to map the machine's parts, functions and then produce a user manual. This was done by first mapping the location of the machine's axles and its functions. The staff at the planer were then interviewed to sort out difficulties and problems with the machine. A problem solution that solves the most common errors has been produced. A maintenance plan has been developed to facilitate maintenance of the machine. A quote for a software update has been sent to the machine programmer. A quote regarding a safety device for the machine has been sent to the machine manufacturer. The result is a fully usable, easy-to-read user manual. The purpose has not been fully fulfilled as the operator has not had time to test the instructions.

This thesis work was conducted at Luleå University of Technology in collaboration with Sandvik Rock Tools. The aim of the work was to determine the influence of carbon content on the wear performance in carburized steel in the dry contact interface of threaded connections between drill rods. In order to investigate this, samples of drill rod steel were carburized to three different carbon concentrations and shot peened to replicate the production process of a drill rod. The samples were wear tested by utilizing a twin-disc wear tester with one disc rotating at 100 RPM and the other at 3000 RPM to mimic the operating conditions in the threaded connection between drill rods. The results was evaluated by wear rate, surface topography, hardness as well as optical analysis by light optical microscopy and scanning electron microscopy. The results show that an increased surface carbon content provide a decrease in wear rate and an increase in hardness in the surface layer that undergo microstructural changes due to the frictional heat and contact pressure during wear testing. The primary wear mechanisms were identified as plastic deformation, adhesive scratching and material removal through delamination.

The challenges faced in today’s industry require materials capable of working in chemically aggressive environments at elevated temperature, which has fueled the development of oxidation resistant materials. All-Oxide Ceramic Matrix Composites (OCMC) are a promising material family due to their inherent chemical stability, moderate mechanical properties, and low weight. However, limited information exists regarding their behavior when in contact with other high-temperature materials such as superalloys. In this work three sets of tribological tests were performed: two at room temperature and one at elevated temperature (650 °C). The tests were performed in a pin-on-disk configuration testing Inconel 718 (IN-718) pins against disks made with an aluminosilicate geopolymeric matrix composite reinforced with alumina fibers (N610/GP). Two different loads were tested (85 and 425 kPa) to characterize the damage on both materials. Results showed that the pins experienced ~ 100 % wear increase when high temperature was involved, while their microstructure was not noticeably affected near the contact surface. After high temperature testing the OCMC exhibited mass losses two orders of magnitude higher than the pins and a sintering effect under its wear track, that led to brittle behavior. The debris generated consists of alumina and suggests a possible crystallization of the originally amorphous matrix which may destabilize the system. The data suggests that while the composite’s matrix is stable, wear will not develop uncontrollably. However, as soon as a critical load/temperature combination is attained the matrix is the first component to fail exposing the reinforcement to damage which drastically deteriorates the integrity of the component.