i will answer with the question followed by the answer.
Question: Results of Induction Sintering of Zirconia.
Answer: Zirconia is a non conductive material, which is a useful property in the dental industry, as it does not create hot and cold sensations orally. Induction works well for metals and metal alloys as the object itself is heated and not the environment around the object, therefore a material such as zirconia that is non conductive would not heat well. Sintering furnaces therefor on the market are for the most part convection types, very similar to porcelain ovens, as it produces more esthetic results.
Question: Does the Yttria content alter the zirconia's time to sinter or high sintering temperature?
Answer: Yttria is a stabalizer as zirconia by itself is an unstable element. Adding different quantities of Yttria changes the properties of zirconia ie. translucency can be affected by addition of slight amounts of Yttria. That being said the Yttria content does not alter the time to sinter for Tetrahedral types of zirconia.
Question: What is the fastest you can cool zirconia?
Answer: A typical recommended is that you cool 8-10 degrees Celcius per minute to at least 450 degrees Celcius and then a natural cool to room Temperature.
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