Critical Assessments of Tensile Ductility in Superplastic TZP and TiO&lt;SUB&gt;2&lt;/SUB&gt;-doped TZP

Kondo, Tomoki; Takigawa, Yorinobu; Ikuhara, Yuichi; Sakuma, Taketo

doi:10.2320/matertrans1989.39.1108

Cited by 30 publications

(32 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As discussed in our previous paper, 20) Q sup and Q gg are the main parameters to determine the elongation to failure in superplastic ceramics. The peak value of elongation to failure decreases, and the temperature region for superplastic flow lowers with a reduction of the activation energies.…”

Section: )mentioning

confidence: 99%

“…The peak value of elongation to failure decreases, and the temperature region for superplastic flow lowers with a reduction of the activation energies. 20) This must be the situation of TiO 2 doping into TZP. Another factor influencing the tensile ductility is C. It has experimentally been verified that the flow stress increases with an increase of grain size in fine-grained TZP.…”

Section: )mentioning

confidence: 99%

See 1 more Smart Citation

Criterion for High Temperature Failure and Grain Boundary Chemistry in Superplastic TZP

et al. 2004

Self Cite

View full text Add to dashboard Cite

Temperature and strain rate dependence on high temperature elongation to failure in fine-grained ceramics is phenomenologically explained from grain growth behavior during deformation and the superplastic flow behavior. The elongation to failure at temperatures between 1573 and 1773 K was analyzed for 2 mol% TiO 2 and 2 mol% GeO 2 co-doped tetragonal zirconia polycrystal (TZP), which exhibits excellent high temperature ductility. The improvement in the high temperature ductility in TZP is attributed to dopant cation segregation in the vicinity of the grain boundaries. The phenomenological analysis revealed that co-doping of Ti and Ge cations increases the grain size at the time of failure, as a parameter to describe a limit of an accommodation process for superplastic flow. The parameter of the critical grain size at the time of failure correlates well with the value of overlap population in cation-doped TZP model cluster obtained from a first-principle molecular orbital calculation. The covalent bond at the grain boundaries plays a critical role in the high temperature tensile ductility of TZP.

show abstract

Section: )mentioning

confidence: 99%

Section: )mentioning

confidence: 99%

Criterion for High Temperature Failure and Grain Boundary Chemistry in Superplastic TZP

et al. 2004

Self Cite

View full text Add to dashboard Cite

show abstract

“…5,6) This method is an application of enhanced superplasticity in TiO 2 -doped TZP, 7) which is explained from the balance between the grain size and the increased accommodation length for the stress concentration by diffusion. 8,9) It is well known that zirconia ceramics shows the martensitic phase transformation preferentially at the surface of tetragonal zirconia. It has been shown that tetragonal to monoclinic (t-m) transformation at the surface of zirconia ceramics is accelerated by the presence of water molecules in the environment.…”

Section: Introductionmentioning

confidence: 99%

Effect of Titania Doping on Phase Stability of Zirconia Bioceramics in Hot Water

2007

Self Cite

View full text Add to dashboard Cite

The effect of titania doping on tetragonal to monoclinic (t-m) phase transformation of zirconia bioceramics is evaluated by ageing in hot water at 413 K. The examined materials are 3 mol%Y 2 O 3 stabilized tetragonal zirconia polycrystal (3Y-TZP) and 1.5, 3.0 and 7.7 mol%TiO 2 -doped 3Y-TZP. The t-m phase transformation of 3Y-TZP is accelerated by titania doping in all the specimen examined. However, 7.7 mol%TiO 2 -doped TZP shows better phase stability than 1.5 or 3.0 mol%TiO 2 -doped one. This change in phase stability of 7.7 mol%TiO 2 -doped TZP cannot be simply explained from the difference of grain size or the change in the axial ratio, c=a. XRD analysis reveals that the distance between nearest neighbor anion and cation site significantly decreases only in 7.7 mol%TiO 2 -doped TZP. This result indicates that the binding energy between dopant and oxygen vacancy affects the phase stability as well as the change in the axial ratio, c=a.

show abstract

“…5) We have also developed an insert material for joining of zirconia dental bridge with a composition of 7.7 mol%TiO 2 -doped TZP, 6,7) by applying enhanced superplasticity in TiO 2 -doped TZP explained from the balance between the grain size and the increased accommodation length for the stress concentration by diffusion. [8][9][10] Thus, it is important to investigate the effect of second phase or dopant on some properties in zirconia bioceramics.…”

Section: Introductionmentioning

confidence: 99%

Effect of Small Amount of Insoluble Dopant on Tetragonal to Monoclinic Phase Transformation in Tetragonal Zirconia Polycrystal

et al. 2009

Self Cite

View full text Add to dashboard Cite

The effect of small amount of insoluble dopant on tetragonal to monoclinic (t-m) phase transformation of 3 mol%Y 2 O 3 stabilized tetragonal zirconia polycrystal (3Y-TZP) is examined by ageing in hot water. The materials used are 3Y-TZP and 0.1 mol%SiO 2 -doped 3Y-TZP with grain size of 0.55 mm. The t-m phase transformation of 3Y-TZP is retarded by 0.1 mol%SiO 2 doping. Since the doped silicon ion segregates along the grain boundaries, the change in phase transformation behavior must be originated from the change in grain boundary diffusivity of hydroxyl ion. Analysis of the transformation kinetics by the Mehl-Avrami-Johnson equation reveals that the activation energy does not change in the two materials but the pre-exponential term significantly changes. Grain boundary diffusion of hydroxyl ion must be blocked by the presence of silicon ion which reduces the effective area of grain boundary diffusion.

show abstract

Critical Assessments of Tensile Ductility in Superplastic TZP and TiO<SUB>2</SUB>-doped TZP

Cited by 30 publications

References 24 publications

Criterion for High Temperature Failure and Grain Boundary Chemistry in Superplastic TZP

Criterion for High Temperature Failure and Grain Boundary Chemistry in Superplastic TZP

Effect of Titania Doping on Phase Stability of Zirconia Bioceramics in Hot Water

Effect of Small Amount of Insoluble Dopant on Tetragonal to Monoclinic Phase Transformation in Tetragonal Zirconia Polycrystal

Contact Info

Product

Resources

About