Oxidation protection of carbon/carbon composite friction materials used in aircraft braking systems is very important as those load bearing materials are constantly exposed to high temperatures. The use of potassium acetate runway deicers instead of urea based materials is of recent concern as it is well known that potassium is a very active catalyst for carbon oxidation. The main goal of this study is to investigate how the aircraft brake materials deteriorates by oxidation when exposed to high temperatures in the presence of potasium acetate. Samples of new and used aircraft wheel brake materials were impregnated with 17.5 % K(+), using KCH3COO as a precursor, by immersion in the K(+) solution, filtered and dried. Oxidation of samples was carried out in air from 500 deg C to 900 deg C. The samples impregnated with potassium were much more reactive than the parent samples. Potassium phases present under reaction conditions were identified as K2O, K2CO3, K2O2 and KCH3COO. Potassium catalytic effect leads to faster gasification. Used brake as more resistant to weight loss in air probably because the more rective carbon fibers were already gasified. Potasssium is present in used brakes leading to carbon fiber removal by catalytic oxidation.
In-situ SEM and in-situ XRD study of C/C composite aircraft brake deterioration by calatytic oxidation
In-Situ-SEM- und In-Situ-XRD-Untersuchung der Beschädigung von C/C-Verbundwerkstoffen in Fluzeug-Fahrwerkbremsen durch katalytische Oxidation
2000
2 Seiten, 5 Bilder, 5 Quellen
Aufsatz (Konferenz)
Englisch
BRAKE DETERIORATION ASSESSMENT DEVICE AND BRAKE DETERIORATION ASSESSMENT SYSTEM
Europäisches Patentamt | 2020
|BRAKE DETERIORATION ASSESSMENT DEVICE AND BRAKE DETERIORATION ASSESSMENT SYSTEM
Europäisches Patentamt | 2019
|ELEVATOR BRAKE DEVICE DETERIORATION PREDICTION SYSTEM
Europäisches Patentamt | 2021
|ELEVATOR BRAKE DEVICE DETERIORATION PREDICTION SYSTEM
Europäisches Patentamt | 2020
|