Comparative Study on Fatigue Life of CFRP Composites with Damages

• Autorzy: Baran Marta , Synaszko Piotr , Lisiecki Janusz , Kłysz Sylwester

Identyfikatory

DOI

10.2478/fas-2019-0004

• Języki publikacji: EN

Abstrakty

EN

In this work, the compressive residual strength tests results, Compression After Impact (CAI), are presented. The specimens were made of carbon-epoxy prepreg E722-02 UHS 130-14. Two variants of specimens were tested: samples undamaged and samples with damage that was centrally introduced by a drop-weight impact, as per the ASTM D7136/7136M standard. An impactor with potential energy equal to 15J and the type of support required by the standard were used. The size of impacted damages, defined as an area of damage on a plane perpendicular to the impact direction, and the equivalent diameter were specified using the flash thermography method. The tests were performed using the fixtures manufactured according to the ASTM D7137/7137M standard. The specimens were compressed to determine the residual strength. This value was afterwards used to specify the force levels for the fatigue tests. The fatigue tests were carried out under force control – with a sinusoidal shape, stress ratio R equal to 0.1 and frequency f 1Hz. Maximum force in a loading cycle Pmax was being increased after each thousand of cycles N until its value was close to the residual strength determined in the previously mentioned tests. In this work, the following relationships were presented: force-displacement P-δ for both static and fatigue tests and displacement-loading cycles δ-N for fatigue tests. A method of conducting the fatigue tests of CFRP composite was proposed, in which both the CAI specimens and CAI fixture were used. This allowed researchers to accelerate making initial comparisons between the two groups of specimens with damages – grouped relative to the way of conditioning.

Słowa kluczowe

EN

CAI; CFRP; compression; Compression After Impact; damage; drop-weight impact test; fatigue test; residual strength

• Wydawca: Wydawnictwa Naukowe Sieci Badawczej Łukasiewicz - Instytutu Lotnictwa
• Czasopismo: Fatigue of Aircraft Structures
• Rocznik: 2019
• Tom: Iss. 11
• Strony: 28--38
• Opis fizyczny: Bibliogr. 6 poz., rys., tab., wykr.

Twórcy

autor

Baran Marta

• Air Force Institute of Technology, ul. Księcia Bolesława 6, 01-494, Warsaw, Poland

autor

Synaszko Piotr

• Air Force Institute of Technology, ul. Księcia Bolesława 6, 01-494, Warsaw, Poland

autor

Lisiecki Janusz

• Air Force Institute of Technology, ul. Księcia Bolesława 6, 01-494, Warsaw, Poland

autor

Kłysz Sylwester

• Air Force Institute of Technology, ul. Księcia Bolesława 6, 01-494, Warsaw, Poland
• University of Warmia and Mazury in Olsztyn, ul. Michała Oczapowskiego 2, 10-719, Olsztyn, Poland

Bibliografia

• [1] ASTM D7137/D7137M-17. Compressive Residual Strength Properties of Damaged Polymer Matrix Composite Plates.
• [2] ASTM D7136/D7136M-15. Standard Test Method for Measuring the Damage Resistance of a Fiber-Reinforced Polymer Matrix Composite to a Drop-Weight Impact Event.
• [3] Ochelski, S. (2019). Metody doswiadczalne mechaniki kompozytow konstrukcyjnych, Wydawnictwo Naukowe PWN, Warsaw. (in Polish)
• [4] Composite Materials Handbook. Volume 3. Polymer Matrix Composites Materials Usage, Design, And Analysis, Department of Defense Handbook, 2002.
• [5] Sałacinski, M., Synaszko, P., Olesinski D. and Samoraj, P., (2019). Approach to Evaluation of Delamination on the MiG-29’s Vertical Stabilizers Composite Skin. ICAF 2019, Lecture Notes in Mechanical Engineering, Niepokolczycki A. and Komorowski J. (Eds.), pp. 865-873.
• [6] Compression After Impact Research, Laboratory of Strength Testing Materials Report No SP-88/31/2018. AFIT Library. 2018. (in Polish)

Uwagi

EN

1. This work was prepared as part of the Air Force Institute of Technology project called ”MiG” performed under a contract with the Ministry of National Defense. The main goal of the project was to develop a repair technology for CFRP and sandwich structures of a MiG-29 jet fighter, with verification in flight tests as the last stage.

PL

2. Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).