PSI - Issue 59

M. Karuskevich et al. / Procedia Structural Integrity 59 (2024) 175–181 M. Karuskevich et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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To reveal the penetration of the CPCs into the gap between sheets of riveted joints the following procedure has been conducted: a) joints were disassembled; b) mating surfaces were covered by graphite powder; c) graphite power was blown out from the surface; d) black spots with remaining powder revealed the penetration of the CPCs. Fig. 7 shows the areas of the CPCs on the mating surfaces of the riveted joint after preparation.

Fig. 7. CPC on the insight surface of the riveted joint (black zones).

5. Conclusions Despite the high efficiency of the Corrosion Preventive Compounds against corrosion, the selection of the compound for aircraft structures requires test of the probable negative side effects on the fatigue life. Proposed test is based on the assumption of the CPC influence on the friction between the mating surfaces of the riveted joints and expected redistribution of the forces carried by the riveted joint components. It is proved by the tests that the method of the treatment, namely the volume of the compound use for the structure unit covering unit influences the results of the fatigue loading. Limitation of the CPCs volume leads to the eliminating of the negative effect. The effect is explained by the different characters of the friction between the mating surfaces depending on the thickness of the lubricating substances. Thus, the treatment procedure is a critical point of the CPC application. To get the real advantage of the CPC application, the technology must be optimized and mandatory followed. References Aircraft Accident Report. Aloha Airlines, Flight 243, Boeing 737-200, N73711, 1988. Report Number NTSB/AAR-89/03, pp.262. http://www.aviation-safety-bureau.com/aircraft-corrosion.html http://www.splav-kharkov.com/simil2_mat.php?type_id=11&name_id_113=2542&name_id_165=1452&count_mat=286 https://corrosion-doctors.org/Inhibitors/CPCs.htm https://www.chemetall.com/Documents/Media-Library-Documents/Literature/Brochures/2016/catalogue_Ardrox-AV-CIC_216_en_LR_final.pdf Jaya, A., Tiong, U. H., Clark, G. et al., 2010b. Corrosion treatments and the fatigue of aerospace structural joints. Procedia Engineering 2(1), 1523-1529. Jaya, A., Tiong, U. H., Clark, G., 2010a. Surface damage in riveted aircraft aluminium lap joints, in the presence of lubricants. Materials Science Forum 654-656, 2434-2437. Kolkman, H. J., 1982. Effect of penetrant on fatigue of aluminium alloy lap joints [Electronic resource]. Aerospace engineering reports of NAL. National Aerospace Laboratory, 1-18. Kuhlman, S. J. H., Abfalter, G. H., Leard, R., Dante, J., 2003. Environmentally assisted fatigue crack growth rate testing with corrosion prevention compounds. Heat treating and surface engineering. Proc. of the 22nd Heat Treating Society Conf. and the 2nd International Surface Engineering Congress « Heat Treating 2003 » . Indiana, USA, September 15-17, 2003, 347-354. Lyashenko, I. A., 2011. Tribological Properties of Dry, Fluid, and Boundary Friction. Technical Physics, Vol. 56, No. 5, 701-707. O'Neill, P. H., Smith, R. J., 1975. A short study of the effect of a penetrant oil on the fatigue life of a riveted joint. Aeronautical Research Council, C.P. No. 1305. 11-13. Purry, C., Fien, A., Shankar, K., 2003. The effect of corrosion preventative compound on fatigue crack growth properties of 2024-T351 aluminium alloys. International Journal of Fatigue, 25, 1175-1180. Schijve, J., Jacobs F. A., Tromp, P. J., 1977. Effect of an anti-corrosion penetrant on the fatigue life in flight-simulation tests on various riveted joints [Electronic resource]. Aerospace engineering reports of NAL. National Aerospace Laboratory, 1-34.