Publication detail

Oxidation Performance of Cold Spray Ti-Al Barrier Coated gamma-TiAl Intermetallic Substrates

ČÍŽEK, J. MAN, O. ROUPCOVÁ, P. LOKE, K. DLOUHÝ, I.

Czech title

Oxidační odolnost gamma-TiAl intermetalických substrátů s ochrannými vrstvami Ti-Al nanesenými technologií studené kinetizace

English title

Oxidation Performance of Cold Spray Ti-Al Barrier Coated gamma-TiAl Intermetallic Substrates

Type

journal article in Web of Science

Language

en

Original abstract

Four blends of Al powder containing different amounts of Ti were deposited onto Ti-46Al-7Nb substrates as oxidation-protection layers using low-pressure cold spray. The coating morphology and chemical composition were assessed. Optimized heat treatment in protective atmosphere was carried out in order to induce formation of intermetallic phases within the deposits. The specimens were then subjected to 950'C exposure for 100, 250, and 500 hrs and their oxidation performance was monitored using the gravimetric method. It was found that the oxidation rate of the coating-protected specimens was substantially reduced (an increase in the weight gain of 1.37 mg/cm2 after 500 hrs of specimen with Al coating) as compared to their uncoated counterparts (1.21 mg/cm2 after 50 hrs at 900'C). The oxidation rates increased with increasing content of Ti in the coatings. Substantial changes of the coating integrity were recorded after the long-term oxidation testing.

Czech abstract

V rámci této studie byly na substráty slitiny Ti-46Al-7Nb pomocí nízkotlaké technologie kinetického nanášení deponovány čtyři antikorozní vrstvy Al obsahující různá množství Ti. Byla stanovena morfologie a chemické složení vzniklých nástřiků a posléze bylo provedeno optimalizované žíhání vzorků v ochranné atmosféře s cílem tvorby intermetalických fází v nástřicích. Hlavní část studie byla poté dlouhodobá tepelná zátěžová zkouška při 950'C (trvání 100, 250 a 500 hodin), při které byla sledována oxidační odolnost gravimetrickou metodou. Bylo zjištěno, že u depozicí vrstev došlo u vzorků k významnému snížení rychlosti oxidace (nárůst hmotnosti 1.37 mg/cm2 po 500 hod u vzorků s nástřikem Al) ve srovnání s původními, nepovlakovanými vzorky (1.21 mg/cm2 po pouhých 50 hod při 900'C). Rychlost oxidace se se zvyšujícím se obsahem Ti zrychlovala. Po tomto zatěžování rovněž došlo k zásadnímu porušení integrity nástřiků.

English abstract

Four blends of Al powder containing different amounts of Ti were deposited onto Ti-46Al-7Nb substrates as oxidation-protection layers using low-pressure cold spray. The coating morphology and chemical composition were assessed. Optimized heat treatment in protective atmosphere was carried out in order to induce formation of intermetallic phases within the deposits. The specimens were then subjected to 950'C exposure for 100, 250, and 500 hrs and their oxidation performance was monitored using the gravimetric method. It was found that the oxidation rate of the coating-protected specimens was substantially reduced (an increase in the weight gain of 1.37 mg/cm2 after 500 hrs of specimen with Al coating) as compared to their uncoated counterparts (1.21 mg/cm2 after 50 hrs at 900'C). The oxidation rates increased with increasing content of Ti in the coatings. Substantial changes of the coating integrity were recorded after the long-term oxidation testing.

Keywords in Czech

studené kinetické nanášení, oxidační ochrana, TiAl, intermetalika, tepelné zpracování

Keywords in English

cold spray, oxidation protection, TiAl, intermetallics, heat treatment

RIV year

2015

Released

04.04.2015

Publisher

Elsevier

ISSN

0257-8972

Volume

268

Number

4

Pages from–to

85–89

Pages count

5

BIBTEX


@article{BUT110903,
  author="Jan {Čížek} and Ondřej {Man} and Pavla {Roupcová} and Kelvin {Loke} and Ivo {Dlouhý},
  title="Oxidation Performance of Cold Spray Ti-Al Barrier Coated gamma-TiAl Intermetallic Substrates",
  year="2015",
  volume="268",
  number="4",
  month="April",
  pages="85--89",
  publisher="Elsevier",
  issn="0257-8972"
}