Residual Stress in HVOF Thermal Sprayed Coatings(1st Report). In-situ Measurement of Stress Generation during HVOF Thermal Spraying.

Katayama, Seiji; Tashiro, Yasuhiko; Yumoto, Hisami; Taira, Susumu; Fukanuma, Hirotaka

doi:10.2207/qjjws.17.102

Cited by 4 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Authors have also investigated the residual stress by mechanical method and X-ray diffraction (XRD), and suggested how to reduce the tensile residual stresses. However, the arising mechanism of residual stress during thermal spraying is not well-known, because there are few studies about stress history during thermal spraying (6)~ (8).…”

Section: Introductionmentioning

confidence: 99%

Stress Histories of Yttria-Stabilized Zirconia and CoNiCrAlY Coatings during Thermal Spraying

Waki

Fujioka

Kobayashi

2009

JMMP

View full text Add to dashboard Cite

Thermal barrier coating (TBC) systems which are used for insulating the substrates of gas turbine blades from high temperature can be made by thermal spraying. The TBC system has residual stresses because of high temperature deposition and the thermal expansion mismatch in the system. In this study, how the residual stress occurs in TBC system was examined by both experimental measurement and FEM analysis. The Yttria-stabilized zirconia (YSZ) top coating was deposited by atmospheric plasma spraying (APS). CoNiCrAlY bond coatings were deposited by high velocity oxygen-fuel (HVOF) spraying and APS. The temperatures of YSZ, CoNiCrAlYs and substrates were measured during thermal spraying. The temperature of YSZ was the highest and that of CoNiCrAlY(HVOF) was the lowest among the three types of spray processes. The residual stresses were elastically calculated by FEM based on the measured temperature histories. The residual stress of YSZ and CoNiCrAlYs on two types of substrates were also measured by X-ray diffraction method. It was confirmed from FEM analysis that residual stress consisted of primary quench stress and secondary thermal mismatch stress. The quench stress was caused by the quenching of coating particles during deposition which occurs due to the huge thermal capacity of the substrate. The thermal mismatch stress was caused by the difference in linear expansion coefficients between coating and substrate. It was found that not only these two mechanisms but also microcrack formation caused by quench played an important role in the residual stress. The temperatures at which residual stresses might begin to occur in the coatings were shown based on the stress relaxation by microcrack formation. It was also found that peening effect played an important role in the residual stress of HVOF sprayed coating.

show abstract

Section: Introductionmentioning

confidence: 99%

Stress Histories of Yttria-Stabilized Zirconia and CoNiCrAlY Coatings during Thermal Spraying

Waki

Fujioka

Kobayashi

2009

JMMP

View full text Add to dashboard Cite

show abstract

“…Delamination of the ceramic coating is important problem in TBC systems. Residual stress plays an important role on delamination of TBC [1]. Authors [2] had investigated the arising mechanism of residual stress during thermal spraying by both measurement of temperatures and FEM stress analysis.…”

Section: Introductionmentioning

confidence: 99%

A Study of Delamination Mechanism of Thermal Barrier Coating under Thermal Cycling and Aging Condition by Residual Stress History

Waki

Kobayashi

2009

KEM

View full text Add to dashboard Cite

Thermal barrier coatings (TBCs) have been employed for the insulation of substrates from high temperature in gas turbine plants. The TBC system consists of ceramic top coating, metallic bond coating and substrate. Delamination of the ceramic coating is important problem in TBC systems. In this paper, the delamination mechanism was studied by residual stress history under thermal aging and thermal cycle conditions. In-plane residual stress histories of ceramic coating and bond coating after thermal aging and cycling were measured by X-ray diffraction method. The residual stress under thermal cycling was also calculated by FEM analysis. The results obtained were as follows: (1) in-plane surface residual stresses of the coatings scarcely changed regardless of the increase of thermally grown oxidation (TGO). (2) high compressive thermal stress, residual stress at room temperature, in ceramic coating induced by thermal stress did not occur. It was found that stress of ceramic top coating was relaxed by micro cracks and driving stress of delamination was in-plane high compressive stress.

show abstract

Assessment of the properties of sprayed coatings for the thermal barrier applied to the piston of internal-combustion engine

Sonoya

Sekine

Nakamura

2015

Mechanical Engineering Journal

View full text Add to dashboard Cite

Residual Stress in HVOF Thermal Sprayed Coatings(1st Report). In-situ Measurement of Stress Generation during HVOF Thermal Spraying.

Cited by 4 publications

References 0 publications

Stress Histories of Yttria-Stabilized Zirconia and CoNiCrAlY Coatings during Thermal Spraying

Stress Histories of Yttria-Stabilized Zirconia and CoNiCrAlY Coatings during Thermal Spraying

A Study of Delamination Mechanism of Thermal Barrier Coating under Thermal Cycling and Aging Condition by Residual Stress History

Assessment of the properties of sprayed coatings for the thermal barrier applied to the piston of internal-combustion engine

Contact Info

Product

Resources

About