A comprehensive study of microstructure, texture and mechanical properties of Ti-6Al-4V joints produced by inertia friction welding is addressed in this thesis. Axis-symmetric tubular welds of different wall thicknesses were produced using different welding parameters. In the present study, there are two thin wall welds and three thick wall welds. A martensitic transformation occurred in the thin wall welds, resulting from the fast cooling rate, whereas it is prevented in the thick wall welds. The acicular microstructure in the Centre Weld Zone is finer and plastic deformation in the Thermal Mechanical Affected Zone is more severe with a higher energy input. In thick wall welds, prior β grain boundaries and grain boundary α are more clearly observed. Based on the reconstruction of prior β grains, the average β grain size can be related to the exponential of the forged pressure over the average input power density. The mechanical behaviour of both thin wall and thick wall welds for the varied welding parameters is also investigated, including tensile tests, fracture toughness tests, low cycle fatigue and fatigue crack growth resistance tests.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:715569 |
Date | January 2017 |
Creators | Xie, Shuang |
Publisher | University of Birmingham |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://etheses.bham.ac.uk//id/eprint/7420/ |
Page generated in 0.0018 seconds