Shrink-fit ceramics, steel
Shrink-fit ceramics, steel
(OP)
Hi,
I'm looking at the possibility of connecting a cylinder made of Zirconia and a steel housing made of Inconel 625 by heating the steel housing.
The steel housing is a simple pipe with a outer diameter of 50mm. The Zirconia cylindre has a diameter of 40mm and is 40mm long.
The connection has to be strong enough so the Zirconia does not fall out. The system may experience relatively large temperature variations, let's say -50degC to 100degC.
Any information is greatly appreciated.
Thanks
I'm looking at the possibility of connecting a cylinder made of Zirconia and a steel housing made of Inconel 625 by heating the steel housing.
The steel housing is a simple pipe with a outer diameter of 50mm. The Zirconia cylindre has a diameter of 40mm and is 40mm long.
The connection has to be strong enough so the Zirconia does not fall out. The system may experience relatively large temperature variations, let's say -50degC to 100degC.
Any information is greatly appreciated.
Thanks





RE: Shrink-fit ceramics, steel
Patricia Lougheed
Please see FAQ731-376: Eng-Tips.com Forum Policies: Eng-Tips.com Forum Policies for tips on how to make the best use of the Eng-Tips Forums.
RE: Shrink-fit ceramics, steel
RE: Shrink-fit ceramics, steel
RE: Shrink-fit ceramics, steel
The zirconia has quite an enormous compressive strength as long as you take its brittleness into account. You need to carefully avoid stress concentrations in your design which might lead to cracks. At the hottest (or coldest) your parts will ever get in storage or service, the zirconia must still be held with sufficient compressive force inside the steel housing. The zirc part also must never be put into tension or it will break. Sudden transitions from hot to cold will be a worry.
RE: Shrink-fit ceramics, steel
I am not sure I would bother trying to shrink the Zirconia since it is pretty thermally stable. Chilling it would speed up the assembly process.
Where moltenmetals talks about stress concentrations and tension I will talk about the need to have the mating surfaces match pretty close to exactly. Certainly both need to be smooth. The smoothness required will depend on the size of the pieces involved. Also the steel will need to shrink very uniformly.
Tom
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
Good engineering starts with a Grainger Catalog.
RE: Shrink-fit ceramics, steel
I greatly appreciate your advice, thank you.