ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Superplastic behaviors were investigated for fine-grained yttria-stabilized tetragonalzirconia polycrystal (Y-TZP) from a viewpoint of GeO2 or TiO2 doping. It was found that bothdopants enhance the ductility in TZP. In particular, elongation to failure of 988% could be obtainedin 3Y-TZP co-doped with 2mol%GeO2 and 2mol%TiO2. In addition, it was revealed that lower flowstress did not always give a larger elongation in this system. On the other hand, the strongsegregation of dopants along grain boundaries was confirmed by high-resolution electrontransmission microscopy study (HRTEM) with X-ray energy dispersive spectrometer (EDS). Theunique phenomena observed in the relation between flow stress and ductility is closely related to thestrong segregation of dopants along grain boundaries in this system. The grain size at fracture isdetermined by covalency because of the dopant segregation. It could be concluded that elongationto failure is closely related to a balance between grain size at fracture and grain growth rate duringdeformation
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/51/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.317-318.407.pdf
