Residual stress in Pt coatings under thermal influence

Resistance thermometers are commonly employed when accurate temperature measurements are required. The detection part consists of a thin metallic film deposited on a ceramic substrate. In this work, commercially manufactured Pt-Al₂O₃ composites annealed at 0°C, 300°C, 600°C and 1170°C above room temperature were investigated for residual stress using the non-destructive X-ray diffraction technique. The apparatus used for the investigation was a Ψ-goniometer with a scintillation detector. The measured data were analysed with "sin²Ψ"-method. The total stress yielded was found to be a superposition of both the thermal and intrinsic stress in the layer. Analytical model, following the method of Tsui and Clyne, was used to resolve the two stress contributions. With the thermal component being constant, the variation of the observed total stress was attributed to the relaxing intrinsic components. Further investigations of the samples included the microstructure studies using Scanning Electron Microscopy (SEM).

Grantor dc:publisher.institution

Department of Physics

Year dc:date.issued

2001

Author dc:creator

• Ntsoane, T P

Advisor dc:contributor.advisor

• Härting, Margit

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/8778

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/8778