Today's competitive market requires engineers to produce reliable light weight products at low cost. This can be achieved by more effective use of computer aided engineering tools during early stages of the design process. A research programme has been undertaken to investigate the data requirements of integrating commercially available software packages (finite element analysis and fatigue life evaluation) to evaluate the integrity and durability of engineering components at the conceptual design stage. A real engineering component, in the form of a steering arm, supplied by a European truck manufacturer was used as a basis for the investigation. This is a typical vehicle component, in which, under service loading conditions, a multiaxial state of stress occurs. A geometric model of the component was created using the Prime "MEDUSA" software suite. The model was used to locate the boundary co-ordinates necessary for the development of a PAFEC Finite Element model. By imposing the conditions experienced during the service, the critical areas of the component were identified by analysing the F.E. model and a detailed description of the elastic stress/strain fields were also established. These were incorporated in an energy density approach and Neuber's uniaxial analysis to predict total local elastic/plastic strains at these critical- locations. These were compared with strain gauge measurements. The calculated results were used to plot a number of load/local strain calibration curves for the development of a load history, suitable for experimental fatigue life assessment. Fatigue crack initiation tests were performed on the steering arm using a computer controlled DARTEC multiaxial fatigue testing machine. Fatigue life assessment based on full service loading was carried out using a software package based on the critical location approach. A comparison of computerised, experimental and actual test circuit fatigue lives has been made. The work enabled a specification to be produced for the integration of the two items of software. This integrated software was developed by third parties and used to produce a computerised life map of the steering arm.

Sustainability is a major focus for the industry considering the awareness among the public and legislators due to climate change. Automotive manufacturers use many steel products for assembly of vehicles and, many of these products; particularly the heavy and critical components like Front Axle beams and Crankshafts are manufactured using forging process. Due to increased awareness and regulations, all companies are expected to provide environmental impact data relevant to their products. Nonetheless, providing environmental impact data is not yet a common practice in the manufacturing industry, specifically in case of the forged products. Therefore, this thesis aims to establish a comprehensive study of environmental impacts of products namely Heavy vehicle Front Axle Beams, Heavy vehicle Crankshafts, Passenger car Crankshafts and Heavy vehicle steering arms forged at Bharat Forge Kilsta AB and create a baseline for current impact calculations as well as highlight areas for improvement in the future. Lifecycle Assessment (LCA) is used as the method to study the environmental impacts of the forged products. The LCA method in this case is based on ISO 14044 and ILCD Handbook and the impact assessment methods used are EPD (2018) and Cumulative Energy Demand (LHV) v1.0 in accordance with EPD International’s requirements. This research finds that steel and the electricity used in the forging process are the major causes of environmental impacts. To ensure high accuracy of the results of this study, primary data for both steel and electricity is used in the analysis. The LCA results will be published in the form of Environmental Product Declaration (EPD). The CO2 footprint for an average product was found to be 0.89 kg CO2 / kg forged product. Previous studies have utilised average datasets for calculating environmental impacts of forged products which reduce the accuracy of the results. This study, due to the inclusion of primary data of steel manufacturing and electricity generation, provides highly accurate environmental impact results of forged products. / Hållbarhet är ett stort fokus för branschen med tanke på medvetenheten hos lagstiftare och allmänheten på grund av klimatförändringar. Biltillverkare använder många stålprodukter för montering av fordon och många av dessa produkter; speciellt de tunga och kritiska komponenterna som framaxelbalkar och vevaxlar tillverkas med hjälp av smidesprocess. På grund av ökad medvetenhet och bestämmelser förväntas alla företag tillhandahålla data på miljöpåverkan som är relevanta för sina produkter. Icke desto mindre är det ännu inte vanligt att tillhandahålla miljöpåverkansdata inom tillverkningsindustrin, särskilt när det gäller smidesprodukter. Därför syftar denna avhandling till att upprätta en omfattande studie av miljöpåverkan från produkter, specifikt framaxelbalkar för tunga fordon, vevaxlar för tunga fordon, vevaxlar för personbilar och styrarmar för tunga fordon smidda hos Bharat Forge Kilsta AB och skapa en bas för aktuella påverkansberäkningar och för att belysa framtida förbättringsområden. Lifecycle Assessment (LCA) används som metod för att studera de smidda produkternas miljöpåverkan. LCA-metoden i detta fall är baserad på ISO 14044 och ILCD Handbook och de konsekvensbedömningsmetoder som används är EPD (2018)och Cumulative Energy Demand (LHV) v1.0 i enlighet med krav från EPD International. Denna forskning visar att stål och elektricitet som används i smidesprocessen är de främsta orsakerna till miljöpåverkan. För att säkerställa hög noggrannhet av resultaten av denna studie används primärdata för både stål och el i analysen. LCA resultaten kommer att publiceras i form av Environmental Product Declaration (EPD). CO2-avtrycket för en genomsnittlig produkt visade sig vara 0,89 kg CO2/kgsmidd produkt. Tidigare studier har använt genomsnittliga datamängder för att beräkna miljöpåverkan från smidda produkter som minskar noggrannheten i resultaten. Denna studie, på grund av inkluderingen av primärdata för ståltillverkning och elproduktion, ger mycket exakta miljöpåverkansresultat av smidda produkter.