Thin-film temperature sensors for gas turbines

Thesis/Dissertation · Wed Dec 31 23:00:00 EST 1986

OSTI ID:5990424

Prakash, S

Development of technology for fabrication of thin-film temperature sensors on turbine blades that would remain adherent and at the same time function accurately under operating conditions was studied. The sensor system, essentially a thin-film thermocouple, consists of a multilayered coating structure where the critical aspects include adherence and purity of the layers, electrical insulation, interfacial stability at high temperatures, etc., among numerous others that had to be evaluated and optimized. The Activated Reactive Evaporation process for development of a pure, defect-free, insulating oxide layer was found effective, and vacuum treatment also found effective for increasing adherence. The use of Pt/sub x/O/sub 1-x/ interlayer prior to the deposition of the platinum (and platinum-rhodium) films onto the oxide improved the adherence of the noble metal films considerably, even under thermal-cycling conditions. The sputtering behavior of platinum in argon/oxygen discharges was marked by unusual characteristics of current vs. percent oxygen, i.e., of first decreasing, remaining constant, and finally rising sharply at about 70% oxygen. The behavior could be explained by exclusive argon bombardment of the target up to 70% oxygen. Oxygen getters the platinum being sputtered.

• Research Organization: California Univ., Los Angeles (USA)
• OSTI ID: 5990424
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
034000* -- Natural Gas-- Combustion
42 ENGINEERING
421000 -- Engineering-- Combustion Systems
440300 -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
ADHESION
FILMS
GAS TURBINES
MACHINERY
MEASURING INSTRUMENTS
TEMPERATURE MEASUREMENT
THERMOCOUPLES
THIN FILMS
TURBINE BLADES
TURBINES
TURBOMACHINERY