Deliverables
An understanding of how glass composition and heat treatment influences the subsequent microstructure of fluorphlogopite glass-ceramics and how aspect ratio of the fluorphlogopite crystals and their interconnectivity can be controlled to give the house of cards microstructure associated with machinability.
The machinability of approximately 30 glass-ceramic materials was characterised by an instrumented lathe capable of measuring the forces generated during a turning operation. The microstructure and hardness were measured. Machinability was correlated with hardness, microstructure and the particle size of the machined swarf produced. One particular glass composition and a range of heat treatments were identified as being more machinable than the existing commercial material Macor.
A understanding of how mechanical properties (fracture toughness flexural strength, hardness, moduli, heat distortion temperature) are influenced by glass composition and microstructure in fluorphlogopite glass-ceramics has been obtained.
A basic understanding of how electrical properties such as conductivity, dielectic constant and dielectric loss are influenced by glass composition.
Elephant investigated the machining of crowns using their Cicero CAD CAM system. The machinability was good and prototype crowns were produced. The machining conditions were found to be very different for Zirconia and alumina.
Prototype crowns were also machined using a CEREC machine, which is used chairside in a dental surgery. The machining time was 16 mins, which is attractive for this application (zirconia and alumina take about 3Hrs to machine with this system). Dimensional fit of the crowns was good and the TEC was close to alumina allowing dental porcelains used for overglazing alumina to be used.
Detailed understanding of how glass composition in SiO2-Al2O3-B2O3-MgO-MgF2-BaO/K2O glasses influences glass properties, nucleation and crystallization behaviour of fluormica glass-ceramics.
Results will be published in reputable scientific journals. Aspects which apply to the compositions developed by the University of Leeds will be kept confidential.
A thorough understanding of how glass composition influences the nucleation and crystallisation behaviour of glasses from the ternary system barium fluorphlogopite-cordierite-tricalcium phosphate has been established.
The parameters that influence crystal nucleation of the fluorphlogopite phase have been established.
Other partners in the consortium have characterised the microstructural development (CRIBC, machinability (Morgan Matroc) and Mechanical properties of these compositions(MI).
Searching for OpenAIRE data...
There was an error trying to search data from OpenAIRE
No results available