Print Email Facebook Twitter On the applicability of selective laser melting on pistons for the oil & gas industry Title On the applicability of selective laser melting on pistons for the oil & gas industry: Fatigue limit and fracture toughness of selective laser melted TI6AL4V Author Niehaus, Anya (TU Delft Mechanical, Maritime and Materials Engineering; TU Delft Materials Science and Engineering) Contributor Rans, C.D. (mentor) Kumar, Siddhant (graduation committee) Degree granting institution Delft University of Technology Programme Materials Science and Engineering Date 2022-12-01 Abstract Pistons for reciprocating compressors for industrial applications are often made of specialised materials. These prove to have problems with manufacture due to the high quality and short production times needed in combination with a low production volume per design. Additive manufacturing, specifically selective laser melting, could solve the production problems, provided that the material retains the needed mechanical properties. Ti6Al4V is the most appropriate material for this application. The most important mechanical properties for the application are the fatigue limit and the stress intensity factor, which are not well established properties for printed materials. For this reason fatigue limit and stress intensity factor tests were performed for both stress relieved and hot-isostatic pressed test pieces on longitudinal and transverse directions. Strength, toughness and fatigue limit is higher in hot-isostatic pressed test pieces of Ti6Al4V, and these are proven to be appropriate for application in compressor pistons. However the fatigue limit of stress relieved Ti6Al4V is lower, anisotropic, and has more scatter, and as such is insufficient for the application, which is due to deleteriously oriented microstructure and the presence of porosities. This can be solved by changing the printing parameters – laser power, cooling rate or heat treatment – although the exact combination of parameters for optimised values is not known and will be part-specific. Subject Selective Laser MeltingFatigueFracture toughnesReciprocating compressorPistonMicrostructureFractographyTi6Al4V To reference this document use: http://resolver.tudelft.nl/uuid:7b53d744-c975-473f-b0db-302f69c209e4 Part of collection Student theses Document type master thesis Rights © 2022 Anya Niehaus Files PDF Niehaus_On_the_applicabil ... dustry.pdf 6.86 MB Close viewer /islandora/object/uuid:7b53d744-c975-473f-b0db-302f69c209e4/datastream/OBJ/view