Aqueous colloidal processing of PLZT ceramics near the morphotropic phase boundary

Abstract

Single phase PLZT powder was fabricated using the mixed oxide approach, with a composition (6/60/40) lying on the rhombohedral-tetragonal (morphotropic) phase boundary. Aqueous suspensions showed an IEP of pH 9·7 in the absence of a polyelectrolyte surfactant. Inductively coupled plasma optical emission spectrometry analysis demonstrated considerable leaching of Pb²⁺ and La³⁺ ions under acidic conditions. The addition of an ammonium salt of poly(methacrylate), or PMA-NH₄, decreased the IEP to pH 5-6. Suspensions were readily stabilised at basic pH using low PMA-NH₄ concentration (<0·1 wt-% of solids). Concentrated suspensions exhibited shear thinning behaviour under low shear rates, with a transition to shear thickening at modest rates (i.e. 100 s⁻¹). Excessive shear thickening imposed a maximum solids loading of 46 vol.-% on concentrated suspensions, which related to the somewhat ‘flake-like’ particle morphology. Slip casting resulted in green and sintered (1250°C for 30 min) densities of 56±1% and 98·3±0·6% of theoretical, respectively.

Keywords

Colloidal processing Zeta potential Rheology Slip casting Sintering Ferroelectric

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References

Lange

F. F.

: J. Am. Ceram. Soc., 1989, 72, 3–15.

Lewis

J. A.

: J. Am. Ceram. Soc., 2000, 83, 2341–2359.

Haertling

G. H.

: J. Am. Ceram. Soc., 1999, 82, 797–818.

Navarro

, Alcock

and Whatmore

: J. Eur. Ceram. Soc., 2004, 24, 1073–1076.

Traiphol

: J. Ceram. Process. Res., 2007, 8, 137–141.

and Cheng

: J. Am. Ceram. Soc., 2002, 85, 1735–1837.

Galassi

, Roncari

, Capiani

and Pinasco

: J. Eur. Ceram. Soc., 1997, 17, 367–371.

Feng

J. H.

and Dogan

: J. Am. Ceram. Soc., 2000,83, 1681–1686.

Ratinac

K. R.

, Standard

O. C.

and Bryant

P. J.

: J. Colloid Interf Set, 2004, 273, 442–454.

10.

Suntako

, Laoratanakul

and Traiphol

: Ceram. Int., 2009, 35, 1227–1233.

11.

Windle

and Derby

: J. Mater. ScL Lett., 1999, 18, 87–90.

12.

Bhatti

A. R.

, Mott

, Evans

J. R. G.

and Edirisinghe

M. J.

: J. Mater. Set Lett., 2001, 20, 1245–1248.

13.

Smay

J. E.

, Cesarano

Tuttle

B. A.

III and J. A. Lewis: J. Am. Ceram. Soc., 2004, 87, 293–295.

14.

Rocks

S. A.

, Wang

, Sun

, Jayasinghe

S. N.

, Edirisinghe

M. J.

and Dorey

R. A.

: J. Electroceram., 2007, 19, 287–293.

15.

Meng

C. H.

, Wei

W. C. J.

, Shieh

and Chen

C. S.

: J. Ceram. Proc. Res., 2006, 7, 281–287.

16.

Zeng

Y.-P.

, Zimmermann

, Aldinger

and Jiang

: J. Eur. Ceram. Soc., 2008, 28, 2597–2604.

17.

Prabhakaran

, Jayasingh

E. M.

, Raghunath

, Durgaprasad

and Sharma

S. C.

: Adv. Appl. Ceram., 2009, 108, 145–148.

18.

Feng

J. H.

and Dogan:

Mater. Set Eng. A, 2000, A283, 56–64.

19.

Cho

J. M.

and Dogan

: J. Mater. ScL, 2001, 36, 2397–2403.

20.

Hardtl

K. H.

and Hennings

: J. Am. Ceram. Soc., 1972,55, 230–231.

21.

Kamiya

, Sasai

and Itoh

: J. Ceram. Soc. Jpn, 2003, 111, 806–810.

22.

Kamiya

, Sasai

and Itoh

: J. Ceram. Soc. Jpn, 2003, 111, 897–901.

23.

Tang

, Huang

, Zhang

and Guo

: Ceram. Int., 2000, 26, 93–97.

24.

Tsetsekou

, Agrafiotis

, Leon

and Milias

, J. Eur. Ceram. Soc., 2001, 21, 493–506.

25.

Hackley

V. A.

and Paik:

in ‘Handbook on ultrasonic and dielectric characterization techniques for suspended particulates’, (ed. Hackley

V. A.

and Texter

), 191–204; 1998, Westerville, The American Ceramic Society.

26.

Tarjan

: ’Mineral processing: fundamentals, comminution, sizing and classification’, 1981, Budapest, Akademiai Kiado.

27.

Waseda

and Muramatsu

: ‘Morphology control of materials and nanoparticles: advanced materials processing and character-ization’, 2003, London, Springer.

28.

Newstein

M. C.

, Wang

, Balsara

N. P.

, Lefebvre

A. A.

, Shnidman

, Watanabe

, Osaki

, Shikata

, Niwa

and Morishima

: J. Chem. Phys., 1999, 111, 4827–4838.

29.

Bergstrom

: in ‘Handbook of applied surface and colloid chemistry’, (ed. Holmberg

), 201–218; 2001, New York, John Wiley & Sons.

30.

Hoffman

R. L.

: J. Rhea, 1998, 42, 111–123.

31.

Bossis

and Brady

J. F.

: J. Chem. Phys., 1989, 91, 1866–1874.

32.

Guo

, Cai

, Li

, Nan

and Gui

: Ceram. Int., 2003, 29, 403–406.

33.

Smay

J. E.

and Lewis

J. A.

: J. Am. Ceram. Soc., 2001, 84, 2495–2500.

34.

Barnes

H. A.

: J. Rhea, 1989, 33, 329–366.

35.

Jean

and Wang

: J. Am. Ceram. Soc., 1998, 81, 1589–1599.