Zirconia Flashcards
1
Q
2024 Cesar Shang Recent Advances in Zirconia
1. What happens during zirconia sintering? What happens the longer you sinter?
2. What are some advantages of short sintering?
3. What are downsides?
A
- Densification via reduction of the porosity and junction of the powder particles. Longer you sinter, the bigger the grain sizes.
- One study found higher flexural strength (, shorter time
- Reduced translucency due to isolated tiny pores (light scatter)
2
Q
What are heatless stones made out of?
A
Silicon carbide
3
Q
At what temps does zirconia exist in its different phases?
A
Below 1170˚C: Monoclinic
1170-2370˚C: Tetragonal
Above 2370˚C: Cubic
4
Q
How much vol % change when Zirconia changes phase from tetragonal to monoclinic?
A
5%
5
Q
Noble metals do not oxidize easily. What elements are added to alloys in order to facilitate the oxide layer formation for ceramic veneering?
What can cause some alloys to become green?
A
Easily oxidized elements, like indium and tin.
Green: Silver
