Residual stress disribution in brazed zirconia-iron joints
- Oak Ridge National Lab., Oak Ridge, TN (United States); and others
Modern structural applications (e.g., advanced engine design) require materials of sustained high strength at high temperatures. This requirement often cannot be satisfied with conventional monolithic materials. A promising alternative is a combination of materials such as ceramic/metals. The joining of such dissimilar materials can be achieved by, for example, brazing of ceramics to metals. However, during the brazing cycle, as the brazed joint cools down from a high temperature to room temperature, residual stresses develop and remain within the joint as a result of the thermal expansion mismatch between the ceramic and metal parts. A detailed understanding of the residual stress state in the joints is therefore essential to the development of high strength joints. To meet this demand, a neutron residual stress mapping system was developed at the High Flux Isotope Reactor of Oak Ridge National Laboratory. In the present paper, we report for the first time a complete nondestructive mapping of the residual stresses in a brazed zirconia-iron joint. Despite these difficulties, using a high flux neutron source, we were able to map the residual stresses in the joint specimen with a sampling volume as small as 1.5 x 1.5 x 2 mm. The experimentally determined residual strains were compared with a finite element model incorporating the effects of plastic deformations. It is shown that the strain distribution in the iron can be well described with the finite element model.
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 115450
- Report Number(s):
- CONF-9404233-; TRN: 95:002927-0028
- Resource Relation:
- Conference: 75. American Welding Society (AWS) annual meeting, Philadelphia, PA (United States), 10-15 Apr 1994; Other Information: PBD: 1994; Related Information: Is Part Of 75th Diamond anniversary American Welding Society annual meeting; PB: 273 p.
- Country of Publication:
- United States
- Language:
- English
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