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För att nå de svenska klimatmålen om att minska växthusgasutsläppen från inrikes transporter (undantaget flyget) med 70 % till 2030 och om att nå nettonollutsläpp för samtliga sektorer till 2045 behöver användningen av förnybar energi i transportsektorn öka. Denna studie kvantifierar kostnadsstrukturer och analyserar riskfördelning mellan olika aktörer för fossilfria framdriftstekniker för tunga långväga godstransporter på väg. Följande tekniker är inkluderade i studien: biobränslen (flytande och gasformiga), elfordon med batterier (BEV), elvägar (tre olika tekniker), vätgasdrivna bränslecellsfordon samt elektrobränslen. I denna studie görs också en jämförelse avseende de olika framdrivningsteknikernas växthusgasutsläpp där bränsle/energianvändning, batteriproduktion (för tekniker med elektrisk framdrivning) och elvägsinfrastruktur inkluderas. Analyserna görs för två typer av lastbilar: HGV40 och HGV60. HGV40 är en tung lastbil med en tillåten bruttovikt om max 40 ton som används inom hela Europa. HGV60 är en lastbil med en tillåten bruttovikt om max 60 ton som står för merparten av transportarbetet med lastbil i Sverige, men som bara är tillåten i ett fåtal andra europeiska länder. Beräkningar görs för år 2030 och 2045. Kostnader för de olika teknikalternativen redovisas i vad vi i denna studie har valt att kalla relativ mobilitetskostnad. Den relativa mobilitetskostnaden inkluderar: fordonens investeringskostnader, service och reparationer av fordon samt drivmedelskostnader. Drivmedelskostnaderna består av produktions- och distributionskostnader för drivmedel, där distributionskostnaderna inkluderar både direkta kostnader för distribution av drivmedel från produktionsanläggning till pump, samt investeringskostnader och underhåll för distributionsinfrastruktur (d.v.s. underhåll för elväg, ladd-infrastruktur eller tankstation). Genom att tydligt presentera de olika delarnas bidrag till den relativa mobilitetskostnaden erhålls en bild av hur kostnaderna för de olika framdrivningsteknikerna fördelar sig mellan fordonsinvestering, service och reparation av fordon, drivmedelsproduktionskostnader och distributionsinfrastruktur. Alla kostnader beräknas utan skatter och avgifter. En analys som visar påverkan på den relativa mobilitetskostnaden då man belastar alternativen med en CO2e-kostnad för bränsle/energianvändningen inkluderas också i studien. Studiens sammanställning av hinder och risker för de olika alternativen baseras på kostnadsanalysen, växthusgasjämförelsen och en litteraturgenomgång med fokus på ekonomiska, tekniska, infrastrukturrelaterade risker men också miljöpåverkan och tillgång på råvaror.

Användningen av förnybar energi i transportsektorn behöver öka för att vi ska nå de svenska klimatmålen om minskade växthusgasutsläpp från inrikes transporterna med 70 procent till 2030, och nettonollutsläpp från samtliga sektorer till 2045. Ökningen av förnybara drivmedel behöver ske i alla segment och över hela fordonsflottan. Idag används främst diesel som drivmedel för tunga långväga godstransporter på väg men det finns alternativ för fossilfri framdrift. Denna studie har kvantifierat kostnadsstrukturer och analyserat riskfördelning mellan olika aktörer för fossilfria framdriftstekniker för tunga långväga godstransporter på väg och jämfört dem med alternativet att fortsätta använda diesel som drivmedel. Följande tekniker är inkluderade i studien: biobränslen (flytande och gasformiga), batterielektriska fordon (BEV), elvägar (tre olika tekniker), vätgasdrivna bränslecellsfordon (H2-FCEV) samt elektrobränslen. Beräkningar görs för år 2030 och 2045. Från de fem huvudkategorierna för fossilfri framdrift har ett antal representativa motortekniker, bränsleproduktionstekniker och råvaror valts ut för att analyseras i detalj. Detta har resulterat i ett trettiotal olika fossilfria alternativ till dagens användning av fossil diesel

Emission regulations for heavy-duty diesel engines are becoming increasingly restrictive to limit the environmental impacts of exhaust gases and particles. Increasing the specific power output of diesel engines would improve fuel efficiency and greatly reduce emissions, but these changes could lead to increased exhaust gas temperature, increasing demands on the exhaust manifold material. This is currently the ferritic ductile cast iron alloy SiMo51, containing about 4 wt% Si and ~1 wt% Mo, which operates close to its fatigue and oxidation resistance limits at peak temperature (750C). To ensure high durability at higher temperatures, three different approaches to improving the life of exhaust manifolds were developed in this thesis. The first approach was to modify SiMo51 by adding different combinations of Cr and Ni to improve its high-temperature strength and oxidation resistance, or by applying a thermal barrier coating (TBC) to reduce the material temperature and thereby improve fatigue life. In the second approach, new materials for engine components, e.g. austenitic ductile iron and cast stainless steel, were investigated for their high-temperature fatigue and oxidation properties. In order to identify the most suitable alloys for this application, in the third the environmental effects of the corrosive diesel exhaust gas on the fatigue life of SiMo51 were investigated. The high-temperature oxidation resistance of SiMo51 at 700 and 800C in air was found to be improved by adding Cr, whereas Ni showed adverse effects. The effects of solid-solution hardening from Ni and precipitation hardening from Cr were low at 700C, with improvements only at lower temperatures. Applying a TBC system, providing thermal protection from a ceramic topcoat and oxidation protection from a metallic bond coat, resulted in only small reductions in material temperature, but according to finite element calculations still effectively improved the fatigue life of a turbo manifold. Possible alternative materials to SiMo51 identified were austenitic cast ductile iron Ni-resistant D5S and austenitic cast stainless steel HK30, which provided high durability of exhaust manifolds up to 800 and 900C, respectively. Corrosion fatigue testing of SiMo51 at 700C in diesel exhaust gas demonstrated that the corrosive gas reduced fatigue life by 30-50% compared with air and by 60-75% compared with an inert environment. The reduced fatigue life was associated with a mechanism whereby the crack tip oxidized, followed by crack growth. Thus another potential benefit of TBC systems is that the bond coat may reduce oxidation interactions and further improve fatigue life. These results can be used for selecting materials for exhaust applications. They also reveal many new research questions for future studies. Combining the different approaches of alloy modification, new material testing and improving the performance using coatings widened the scope of how component life in exhaust manifolds can be improved. Moreover, the findings on environmental interactions on SiMo51 fatigue provide a completely new understanding of these processes in ductile irons, important knowledge when designing components exposed to corrosive environments. The novel facility developed for high-temperature corrosion fatigue testing can be useful to other researchers working in this field. QC 20150507

The main purpose of this study was to examine how social workers in Swedish social services reason and construct suitability regarding placing unaccompanied children in kinship care. In total five social workers participated in this study, attending qualitative semi-structured interviews where they ranked twenty characteristics regarding suitability. We wanted to examine their reasoning through theories about childrens needs and the characteristics of suitability regarding the relatives. Through the result we found that social workers in Swedish social services have similar experiences about placing unaccompanied children in kinship care. In their assessments the social workers tend to think about what the children would want for themselves. When it comes to the relatives’ suitability the social workers appreciate the fact that they come from the same culture and speak the same language.

Due to coming emission legislations, the temperature is expected to increase in heavy-duty diesel engines, specifically in the hot-end of the exhaust system affecting components, such as exhaust- and turbo manifolds. Since the current material in the turbo manifold, a ductile cast iron named SiMo51, is operating close to its limits there is a need for material development in order to maintain a high durability of these components. When designing for increased life, many material properties need to be considered, for example, creep-, corrosion- and fatigue resistance. Among these, the present work focuses on the latter two up to 800°C improving the current material by additions of Cr, for corrosion resistance, and Ni, for mechanical properties. The results show improved high-temperature corrosion resistance in air from 0.5 and 1wt% Cr additions resulting in improved barrier layer at the oxide/metal interface. However, during oxidation in exhaust-gases, which is a much more demanding environment compared to air, such improvement could not be observed. Addition of 1wt% Ni was found to increase the fatigue life up to 250°C, resulting from solution strengthening of the ferritic matrix. However, Ni was also found to increase the oxidation rates, as no continuous SiO2-barrier layers were formed in the presence of Ni. Since none of the tested alloys showed improved material properties in exhaust gases at high temperature, it is suggested that the way of improving performance of exhaust manifolds is to move towards austenitic ductile cast irons or cast stainless steels. One alloy showing good high-temperature oxidation properties in exhaust atmospheres is an austenitic cast stainless steel named HK30. This alloy formed adherent oxide scales during oxidation at 900°C in gas mixtures of 5%O2-10%H2O-85%N2 and 5%CO2-10%H2O-85%N2 and in air. In the two latter atmospheres, compact scales of (Cr, Mn)-spinel and Cr2O3 were formed whereas in the atmosphere containing 5%O2 and 10%H2O, the scales were more porous due to increased Fe-oxide formation. Despite the formation of a protective, i.e. compact and adherent, oxide scale on HK30, exposure to exhaust-gas condensate showed a detrimental effect in form of oxide spallation and metal release. Thus, proving the importance of taking exhaust-gas condensation, which may occur during cold-start or upon cooling of the engine, into account when selecting a new material for exhaust manifolds. QC 20130508

In a globalized world, competitiveness is based on the high IP (intellectual property) of our export products and innovations are therefore important for new companies to establish and develop. It´s not enough to just have big international companies but it is also necessary to invest in new companies that can be competitive in the future. By helping entrepreneurs with innovation support in the early stages, new technology-based businesses are established and developed. The purpose of this paper was to examine how innovation support in the early stages affects the establishment and development of new technology-based companies. Furthermore, we investigated how this will affect Sweden's international competitiveness. The theories that we have had as a starting point is the incubator and its dynamics, the resource-based theory, and Tripplehelix-model. The study is based on a qualitative approach where 11 interviews were conducted with representatives from governments, industry and academia. The results showed that the network is an important part of innovation support services for entrepreneurs so that they can invest in their ideas. Without access to State aid for innovation through networking and funding it can be difficult to establish and develop new businesses because entrepreneurs do not always have enough on its own feet. This will affect Sweden's international competitiveness adversely in the long run.