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Due to small repeatability of results of impact strength of adhesive joints, particularly those performed on di erent test machines, the authors were inspired to conduct experimental and numerical research in this eld. e investigation used the Block Shear Test.e authors compared impact strength of samples which were loaded in a normative and nonnormative manner and also the dependence in impact strength with regard to the distance between the impactor's edge and the surface of the bonded joint. e numerical calculations were carried out in the program Ansys, using the Explicit Dynamics module. e authors proposed a way of modelling the impactor of the pendulum hammer. It was found that a change in the direction of applying the load to the sample and rotating the loaded sample piece in relation to the edge of the impactor results in a signi cant change in the Max Principal Stresses. Numerical investigations show that lower values of Max Principal Stresses occur in joints which are characterized by larger impact strength, determined experimentally. It was also noted that moving away the edge of the impactor from the surface of the adhesive joint increases normal stresses perpendicular to the surface of the joint.

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Trwa³ooeae zmêczeniowa tworzywa Epidian 57 Streszczenie-Trwa³ooeae zmêczeniowa tworzyw adhezyjnych jest istotna ze wzglêdu na problem trwa³ooeci zmêczeniowej konstrukcyjnych po³¹czeñ klejowych. Obiektem badañ by³a kompozycja Epidian 57 utwardzana za pomoc¹ trietylenotetraaminy dwiema metodami: 7 dni w temperaturze otoczenia lub 1 h w temp. 60 o C. Badaniom poddawano próbki cylindryczne obci¹¿ane harmonicznym cyklem naprê¿eñ oeciskaj¹cych. Okreoelono przyrost temperatury spowodowany zmiennym obci¹¿eniem oraz porównano trwa³ooeae zmêczeniow¹ tworzywa w zale¿nooeci od sposobu utwardzania. Zmierzono odkszta³cenia badanego materia³u pod wp³ywem obci¹¿enia zmêczeniowego w zale¿nooeci od liczby cykli. Przeprowadzono analizê tych odkszta³ceñ za pomoc¹ modelu Burgersa. Wykazano, ¿e istotne znaczenie w procesie zniszczenia zmêczeniowego badanego tworzywa ma jego pe³zanie w temperaturze otoczenia. S³owa kluczowe: po³¹czenia klejowe, tworzywa adhezyjne, trwa³ooeae zmêczeniowa, zniszczenie zmêczeniowe. FATIGUE LIFE OF EPIDIAN 57 PLASTIC Summary-Fatigue lives of adhesive plastics are important due to fatigue lives of constructional glue joints. Epidian 57 composition hardened with triethylenetetramine in two ways: either 7 days at ambient temperature or 1 hour at temp. 60 ºC was the subject of research. Cylindrical samples loaded with harmonic cycles of compressive stresses were tested. Temperature increase caused by variable loading was determined and fatigue lives of plastics were compared dependently on hardening method. The strain of tested material under fatigue loading, dependently on the number of cycles, was measured. An analysis of strain of viscoelastic material under fatigue loading was done. It was demonstrated that the creep at ambient temperature is very important for the process of fatigue failure of the material tested.

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