suspension system. Inżynieria Materiałowa. 33(6) , 635-638.  Maj, M., Piekło, J. (2009). MLCF – An optimised program of low-cycle fatigue test to determine mechanical properties of cast materials. Archives of Metallurgy and Materials vol. 54 iss. 2 . 393–397. Polish Academy of Sciences. Committee of Metallurgy. Institute of Metallurgy and Materials Science; ISSN 1733-3490.
S. Pysz, E. Czekaj, R. Żuczek, M. Maj and J. Piekło
Jan Karthaus, Simon Steentjes, Daniel Gröbel, Kolja Andreas, Marion Merklein and Kay Hameyer
-298 (1989).  Testing of materials; fatigue test (Woehlertest); definitions, symbols, execution, evaluation, DIN 50100:1978-02 (1978).  Metallic materials - Tensile testing - Part 1: Method of test at room temperature (ISO 6892- 1:2009), DIN EN ISO 6892-1:2009-12 (2009).  Magnetic materials - Part 3: Methods of measurement of the magnetic properties of electrical steel strip and sheet by means of a single sheet tester (IEC 60404-3:1992 + A1:2002 + A2:2009), DIN IEC 60404-3:2010-05 (2010).  Lo C
Tayeb Kebir, Mohamed Benguediab and Abdellatif Imad
damage model for fatigue crack initiation and growth,” Int. J. Fatigue , vol. 88, pp. 197–204, 2016.  N. W. Klingbeil, “A total dissipated energy theory of fatigue crack growth in ductile solids,” Int. J. Fatigue , vol. 25, pp. 117–128, 2003.  S. C. Wu, Z. W. Xu, C. Yu, O. L. Kafka, and W. K. Liu, “A physically short fatigue crack growth approach based on low cycle fatigue properties,” Int. J. Fatigue , vol. 103, pp. 185–195, Oct. 2017.  A. Noroozi, G. Glinka, and S. Lambert, “A two parameter driving force for fatigue crack growth
E. Tillová, D. Závodská, L. Kuchariková, M. Chalupová and J. Belan
17 (1), 4-10 (2011).  E. Tillová, M. Chalupová, L. Hurtalová, J. Belan, Manufacturing Technology 15 (4), 720-727 (2015).  J. Pezda, Archiwes of Foundry Engineering. 13 (1), 143-146 (2013).  M. Rosso, I. Peter, C. Castella, R. Molina, Mater. Today: Proceedings 2 (10), 4949-4956 (2015).  R. González, A. González, J. Talamantes-Silva, S. Valtierra, R.D. Mercado-Solís, N.F. Garza-Montes-de-Oca, R. Colás, Int. J. Fatigue 54, 118-126 (2013).  H.R. Ammar, A.M. Samuel, F
Janusz Lisiecki, Dominik Nowakowski and Piotr Reymer
Seat cushion inserts in military helicopters crew seats, as suggested by the helicopters manufacturers, are made of traditional polyurethane foams.
Elastic polyurethane auxetic foams are materials that exhibit different utility properties compared to traditionally used polyurethane foams, such as polyether or polystyrene foams. All the differences result from the primary physical property of elastic polyurethane auxetic foams which is a negative Poisson’s ratio. Auxetic materials are characterized by better utility properties than conventional foam materials – they can potentially increase safety in the event of a crash and offer higher comfort during regular use. Application of auxetic materials as seat cushion inserts would also decrease harmful health effects of vibrations.
This paper presents the results of the fatigue tests carried out on different foam samples by pressing an indenter into the foams' surface that was much larger than the indenter’s surface. A maximum value of the load used during the test was within a defined range in every fatigue cycle.
In order to test 150×150×50 mm foam samples a special indenter was designed and manufactured according to the PN-EN ISO 3385 and PN-EN ISO 2439 standards. The indenter’s dimensions were consistent with the standards in relation to the tested foams' size.
The fatigue tests of both conventional and auxetic foams were carried out according to the above given standards by applying 80,000 load cycles at 70 cycle/min frequency. Tests of viscoelastic foam and multilayer foam specimens, for which the upper layer was made of viscoelastic foam, were carried out according to the ASTM D 3574 standard applying 12,000 load cycles at 10 cycle/min frequency. All the tests were carried out using the MTS 370.10 strength testing machine.
Changes in thickness and density were determined throughout the tests. Moreover, the influence of the volumetric compression ratio on the fatigue properties of auxetic foam samples and the dependence of foam deflection on the number of cycles were examined. Finally, the test results obtained for conventional and auxetic foams were compared and discussed.
. Pietras, Microstructure of friction stir welded joints of 2017Aaluminium alloy sheets, J. Microsc. 237, 521-525 (2010).  C. Hamilton, S. Dymek, M. Blicharski, Mechanical properties of Al 6101-T6 welds by friction stir welding and metal inert gas, Arch. Metall. Mater. 52, 1, 67-72 (2007).  P.L. Threagill, A.J. Leonard, H.R. Shercliff, P.J. Withers, Friction stir welding of aluminium alloys, Int. Mater. Rev. 54, 2, 49-93 (2009).  C. Zhou, X. Yang, G. Luan, Investigation of microstructures and fatigue properties
Stanisław Mroziński and Michał Piotrowski
-Examination of Cumulative Fatigue Damage Analysis - an Engineering Perspective, Engineering Fracture Mechanics, 25(5/6), 539-571. 8. Miner M. A. (1945), Cumulative Damage in Fatigue, Transactions of the American Society of Mechanicals Engineers Journal of Applied Mechanics, 67, 159-164. 9. Mroziński S. (2011), The influence of loading program on the course of fatigue damage cumulation, Journal of Theoretical and Applied Mechanics, 49, 1, 83-95. 10. Mroziński S., Skocki R. (2012), Influence of temperature on the cyclic properties
REFERENCES STN EN 13 108-1 (2016) Bituminous mixtures. Material specifications. Part 1: Asphalt Concrete (in Slovak) EN 12697-26 (2012) Bituminous mixtures - Test methods for hot mix asphalt - Part 26: Stiffness (in Slovak) EN 12697-24 (2012) Bituminous mixtures - Test methods for hot mix asphalt – Part 24: Resistance to fatigue (in Slovak) Schlosser, F., Mikolaj, J., Zatkalíková, V. Šrámek, J. Ďureková, D. Remek, Ľ. (2013) Deformation Properties and Fatigue of Bituminous Mixtures . Advances in materials Science and Engineering
M. Maj and K. Pietrzak
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