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:
To study the effect of second sintering on intragranular structure and mechanical properties of10vol%Al2O3/3Y-TZP composites, the composites were prepared by ball-milling nano-γ-Al2O3 andnano-ZrO2(3mol%Y2O3), pressing unidirectionally, cold-pressing isostatically, then first sintering at1400°C for 2h and second sintering at 1600°C for 5h in air. The composition and microstructure of thecomposites were examined by X-ray diffractometer and scanning electron microscope, transmissionelectron microscope. The results showed that the second sintering changed the microstructure andfracture mode. After second sintering, the structure of fine grains was changed into the mixed one of largegrains and small grains . Many large grains contained small grains, forming intragranular stucture thatcould be produced by the interblending of not only Al2O3 and ZrO2 but also ZrO2 itself. The intergranularfracture after first sintering was changed into transgranular fracture and intergranular fracture after secondsintering . The second sintering led to grinds growing up and intragranular forming, which enhanced thecontribution of the phase transformation toughening. Although the second sintering resulted in abnormalincrease of grain size, the fracture strength and the fracture toughness of the composite were 667 MPa and12.9 MPa⋅m1/2, respectively, due to the intragranular structure and the enhanced phase transformationtoughening
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/53/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.336-338.1324.pdf
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