The effect of PWHT on weld properties of titanium alloy for refurbishment of aircraft engine exhaust cone

• Autorzy: Ardy H. , Yoewono S. , Sugianto A.
• Języki publikacji: EN

Abstrakty

EN

The mounting bolt hole of aircraft engine exhaust cone was found cracked in the weld area. Exhaust cone material is alfa/beta titanium (Ti-6Al-4V) alloy. The cracked section will be repaired by welding to restore its function. The purpose of this research is to evaluate the effect of post weld heat treatment (PWHT) on ductility, grain size, and shear strength of Ti-6Al-4V plates (0.063 in. thickness) welded by gas tungsten arc welding (GTAW) using commercial purity (CP) titanium wire electrode (AMS 4951H). The weld quality was evaluated by non-destructive and destructive tests, using the acceptance criteria of AWS D17.1 and AWS B2.1 as references. The effect of PWHT was examined by preparing two weld specimens: with and without PWHT at 620 centigrade. Non-destructive inspection by dye penetrant and xray radiography tests revealed that the weld in these two specimens is free from surface and internal defects. Weld specimen without PWHT is brittle and failed during fillet break test, whereas PWHT specimen is ductile and pass the same test. Metallography observation was conducted to measured grain size of base metal and heat affected zone (HAZ). The average grain size of PWHT specimen is 18.40 mi m on base metal and 36.80 mi m on HAZ, and for non-PWHT specimen is 26.85 mi m on base metal and 52.10 mi m on HAZ. Using Hall-Petch approach, the yield strength is calculated about 920 MPa on the base metal of PWHT specimen, which result in the shear strength of about 531 MPa. Under static loading, the shear stress on the outer surface of exhaust cone due to exhaust gas is about 38 MPa, which is much lower than material shear strength.

Słowa kluczowe

EN

engine exhaust cone; Ti-6Al-4V; GTAW; PWHT; microstructure; grain size; stress analysis

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2012
• Tom: Vol. 19, No. 1
• Strony: 9--14
• Opis fizyczny: Bibliogr. 10 poz., rys.

Twórcy

autor

Ardy H.

autor

Yoewono S.

autor

Sugianto A.

• Bandung Institute of Technology Department of Materials Engineering Ganesa 10, Bandung 40132, Indonesia tel.: [phone], fax: [phone] tel.: [phone], fax: [phone],

Bibliografia

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• [2] American Welding Society (AWS), Vol. B2.1: Specification for Welding Procedure and.Performance Qualification, Florida, USA 2005.
• [3] ASM International. Metals Handbook Vol. 2: Properties of Non Ferrous Alloys, 4th. Printing,.USA 1997.
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• [7] Kumar, Bharat. An Illustrated Dictionary of Aviation. United States of America: McGraw.Hill Company Inc. 2004.
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• [9] Porter, D. A., Easterling, K. E., Phase Transformation in Metals and Alloys, 2nd ed., Van.Nostrand Reinhold, New York 1992.
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