Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.684553
Title: Investigating the cyclic performance of laser sintered nylon 12
Author: Amel, Hoda
ISNI:       0000 0004 5921 6500
Awarding Body: University of Sheffield
Current Institution: University of Sheffield
Date of Award: 2015
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Abstract:
The growing demand from industries for light-weight structures calls for manufacturing techniques capable of producing complex optimised designs. Laser Sintering is one of these manufacturing techniques that allow the production of end-use parts directly from computer files with no tooling required. For these parts to be used in industrial applications, their mechanical properties throughout in-service applications must be examined. The focus of the present work is to provide an understanding of the dynamic performance of Laser Sintered Nylon 12 parts. In order to investigate the viscoelastic properties of the material, Dynamic Thermal Mechanical Analysis was performed at different frequencies and temperatures. Samples with three different section thicknesses were produced and the effect of section thickness on their tensile properties was examined. Tension-tension cyclic behaviour of samples was studied and cyclic creep was shown to have a great impact in such behaviour in addition to fatigue. Pure tensile cyclic loading could not be achieved hence fully reversed cyclic loading was chosen as an alternative approach. Samples with different section thicknesses were subjected to fully reversed force-controlled cyclic loading and the effect of section thickness on their fatigue life was studied. The percentage of porosity within the samples was measured and its influence on fatigue life of samples was investigated. Thermal history of the samples was recorded during cyclic testing, to inspect the influence of temperature on their fatigue life. Forced convection was applied to the samples to investigate its possible effect on increasing the fatigue life of samples.
Supervisor: Hopkinson, Neil ; Rongong, Jem Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.684553  DOI: Not available
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