I want to make fused Aluminas with a wide range of doping "almost every oxide with boiling point > 2000 °C" and the effect of these dopings on mechanical properities , but I have a concerns about residual stresses generated when cooling and there effect on either mold or the Alumina itself.
if for example a metal crucible "like Mo or W" is used , the lower thermal expansion of metal cause the Alumina to be in tensile stress and this tensile stress may cause cracks.
if ceramic molds "magnesia or zirconia" are used, the Alumina may put on compression and we can strong gripping effect may result, so to extract the we need to crush mold and cost alot !
my points are:
1- how to calculate resulted residual stress from cooling molten ceramic in a certain crucible ?
2-how to choose the best mold material for casting molten Aluminas ?
sorry for my bad english & thanks in advance .
Residual stress can be calculated using XRD technique.
As for mold materials have you thought of water cooled copper mold?
I mean how to theoritically calculate residual stress not how to measure it.
casting fused alumina in water cooled copper may cause cracks in the sample due to large stress generated , is that right?!
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering