In situ measurement of lattice strains in mixed ceramic cutting tools under thermal and mechanical loads using synchrotron radiation

Journal
Production engineering  
Volume
7
Issue
2-3
Start Page
283
End Page
289
Citation
Production Engineering 2-3 (7): 283-289 (2013)
Publisher DOI
10.1007/s11740-012-0426-2
Scopus ID
2-s2.0-84875613386
Publisher
Springer
To completely understand wear mechanisms of mixed ceramic cutting tools (Al2O3-TiC), residual stress states and the superposition of external loads during hard turning should be investigated. This can be done via X-ray diffraction using high-energy synchrotron radiation to determine lattice strains in the material. For this reason, in first model tests, strain states in mixed ceramics were determined during the application of external loads. An experimental setup was developed to measure lattice strains in the different phases of the ceramic material in situ during thermal, mechanical and thermo-mechanical loading for first reference. The accuracy of the setup was sufficient to clearly determine shifts in lattice parameters in the different phases due to external loads. By applying a thermal load on the mixed ceramic material the two main phases showed different elastic lattice strains. Thus, a slightly lower coefficient of thermal expansion in the Al2O3-phase than in the Ti(O,C)-phase could be determined. This indicated the development of compressive stresses in the Al2O3-phase and tensile stresses in the Ti(O,C)-phase at room temperature. By applying external bending stresses to the mixed ceramic material, for both phases equal lattice strains could be determined. From these strains stresses could be calculated for both phases which were in the same order of magnitude as external stresses. With further in situ investigations of strain and stress states in the different phases of mixed ceramics during friction and turning experiments a more comprehensive characterization of wear mechanisms is possible. © 2012 German Academic Society for Production Engineering (WGP).
Subjects
In situ measurement
Mixed ceramics
Stress state
Synchrotron radiation
X-ray diffraction
DDC Class
670: Industrielle Fertigung
More Funding Information
Gühring oHG