Thermomechanical fatigue characterization of zirconia (8%Y 2 O 3 -ZrO 2 ) and mullite thermal barrier coatings on diesel engine components: Effect of coatings on engine performance

Abstract

8%Y₂O₃-stabilized zirconia (8YPSZ) and mullite (3Al₂O₃·2SiO₂) powders, which were made plasma sprayable by using an organic binder (polyvinyl alcohol), have been plasma spray coated on to the piston head, valves and cylinder head of a 3.8kW single-cylinder diesel engine, previously coated with Ni-Cr-Al-Y bond coat. The engine with components coated with 250 μm thick 8YPSZ and 1 mm thick mullite thermal barrier coatings has been evaluated for fuel efficiency and for endurance during 500 h long rigorous tests. Improved fuel efficiency was shown by the engine with coated components and the results are discussed. The coatings and the coated components have also been examined for phases, microstructure and chemical composition by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). Mullite coatings were found to exhibit increased resistance to microcracking compared with 8YPSZ during the 500 h endurance test.

Keywords

thermal barrier coating partially stabilized zirconia mullite diesel engine thermo-mechanical fatigue fuel efficiency

Get full access to this article

View all access options for this article.

References

Carlson

Thermal barrier coating on high temperature industrial gas turbine engines. NASA CR-135147, National Aeronautics and Space Administration and Energy Research and Development Administration, Ohio, USA, 1977.

Miller

R. A.

Oxidation based model for thermal barrier coating life. J. Am. Ceram. Soc., 1984, 67(8), 517–521.

Bennett

Properties of thermal barrier coatings. Mater. Sci. Technol., 1986, 2, 257–261.

Jones

R. L.

Some aspects of the hot corrosion of thermal barrier coatings. J. Therm. Spray Technol., 1997, 6(1), 77–84.

Parks

W. P.

Hoffman

E. E.

Lee

W. Y.

Wright

I. G.

Thermal barrier coatings issues in advanced land based gas turbines. J. Therm. Spray Technol., 1997, 6(2), 187–192.

Rigney

D. V.

Viguie

Wortman

D. J.

Skelly

D. W.

PVD thermal barrier coating applications and process development for aircraft engines. J. Therm. Spray Technol., 1997, 6(2), 167–175.

Troczynski

Cockcroft

Wong

Thermal barrier coatings for heat engines. In Key Engineering Materials, 1996, Vols 122–124, pp. 451–462.

Vincenzini

Zirconia thermal barrier coatings for engine applications. Ind. Ceram., 1990, 10(3), 113–126.

Parker

D. W.

Improving thermal efficiency with ceramic thermal barrier coatings. In Proceedings of International Symposium on Developments and Applications of Ceramics and New Metal Alloys, Montreal, Canada, 1993, pp. 603–613 (Canadian Institute of Mining, Metallurgy and Petroleum).

10.

Winkler

M. F.

Parker

D. W.

Greener meaner diesels sport thermal barrier coatings. Advd Mater. Processes, 1992, 5, 17–22.

11.

Beardsley

M. B.

Thick thermal barrier coatings for diesel engines. J. Therm. Spray Technol., 1997, 6(2), 181–186.

12.

Yonushonis

T. M.

Overview of thermal barrier coatings in diesel engines. J. Therm. Spray Technol., 1997, 6(1), 50–56.

13.

Fritscher

Schulz

Burner rig performance of density graded EB-PVD processed thermal barrier coatings. In Proceedings of ASME Winter Annual Meeting, New York, 1993, pp. 1–8 (Ceramic Coatings, ASME, Materials Division).

14.

Tsai

H. L.

Tsai

P. C.

D. C.

Characterization of laser glazed plasma sprayed yttria stabilized zirconia coatings. Mater. Sci. Engng A: Struct. Mater., Properties, Microstruct. and Processing, 1993, A161(1), 145–155.

15.

Pierz

P. M.

Thermal barrier coating development for diesel engine aluminum pistons. Surf. Coating Technol., 1993, 61, 60–66.

16.

Ramaswamy

Seetharamu

Varma

K. B. R.

Rao

K. J.

Evaluation of CaO-CeO₂-partially stabilized thermal barrier coatings. Ceram. Int., 1999, 25, 317–324.

17.

Ramaswamy

Seetharamu

Varma

K. B. R.

Rao

K. J.

Thermal shock characteristics of plasma sprayed mullite coatings. J. Therm. Spray Technol, 1998, 7(4), 497–504.

18.

Ramaswamy

Seetharamu

Varma

K. B. R.

Rao

K. J.

A simple method for the preparation of plasma-sprayable powders based on ZrO₂. J. Mater. Sci., 1996, 31, 6325–6332.

19.

Kokini

Choules

B. D.

Takeuchi

Y. R.

Thermal fracture mechanisms in ceramic thermal barrier coatings. J. Therm. Spray Technol., 1997, 6(1), 43–49.

20.

IS 1600-1960: Indian standard code for testing of constant speed IC engines for general purposes.

21.

IS 1601-1960: Indian standard specification for performance of constant speed internal combustion engines for general purposes.

22.

Garvie

R. C.

Nicholson

P. S.

J. Am. Ceram. Soc., 1972, 55, 303.

23.

Thermal loading of diesel engines. Proceedings of Symposium arranged by Internal Combustion Engines Group, 21–22 October 1964. Proc. Instn Mech. Engrs, 1964–5, 179(3c).