Physical Metallurgy (Titanium and Nickel Alloys)
Module Title - Physical Metallurgy (Titanium and Nickel Alloys)
Number of credits – 10
This module looks at the applications of Nickel and Titanium alloys in aero-engines and the land-based gas turbine. The basic operation is first considered: thermodynamics, adiabatic heating in the compressor, efficiency and the need for high temperature resistant materials.
For Nickel based alloys temperature resistance and oxidation resistance in Ni and Ni/Cr alloys are described. Other main topics covered are: developing high temperature strength through second-phase particles; slip in the A3B system, involving disordering/re-ordering; the investment casting process; living with high gas temperatures and lifting issues with creep and fatigue; powder discs and the role of shot-peening.
For Titanium alloys - phase diagrams and the main classifications of the alloys; Widmanstatten structures; higher strength alloys, and “burn resistant” alloys; defects in Ti alloys, and ways forward in Ti alloys, will be included. The potential for inter-metallics and MMCs will also be described
By the end of the module the student should be able to:
- Define the operation of gas turbines and understand the functional requirements of the materials used for their construction;
- Describe the principles of alloy design for turbine blade and disc applications and critically assess the material strengthening and degradation mechanisms;
- Detail the principles of blade and disc fabrication, process developments for improved performance and integrity. Specify manufacturing processes;
- Perform calculations to determine the life of components made of nickel and titanium alloys.