Wyniki wyszukiwania - BazTech

1

Analysis of the Corrosion Resistance of Aircraft Structure Joints with Double-Sided Rivets and Single-Sided Rivets

Kamińska Paulina, Synaszko Piotr, Ciężak Patryk, Dragan Krzysztof

Fatigue of Aircraft Structures

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2020

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Iss. 12

57--68

EN

An important factor having a negative impact on the technical condition of aircraft structure elements is the adverse effect of the atmosphere, which causes formation of corrosion in aircraft structures, especially in riveted lap joints. The electric potential difference between the sheet material and the rivet, in the presence of humid air, may cause electrochemical corrosion. The paper presents specimens that imitate the repair on the Mi-24 helicopter with the use of blind rivets in places where solid double-sided rivets could not be used.The aim of the research was to assess the corrosion resistance of lap joints with the use of single-sided and double-sided rivets. The analysis of corrosion resistance was carried out based on accelerated aging tests in a salt spray chamber. The salt chamber tests were aimed at determining the changes taking place in the specimens exposed to the marine environment. In the course of periodic observations changes in the mass of the specimens and in the form of corrosion losses were recorded. These activities were aimed at determining whether the exposure of specimens in the salt chamber causes electrochemical corrosion or pillowing. In addition, the specimens were subjected to static strength tests to assess the effect of corrosion on the strength properties of riveted joints.

2

Durability assessment of building materials exposed to atmosphere agents by testing in simulated environment

Bochen J.

Architecture Civil Engineering Environment

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2013

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Vol. 6, no. 1

17--25

EN

The paper presents the idea of durability valuation of building materials and elements subjected to the influence of atmospheric environment during their exploitation based on the laboratory tests carried out with the use of climatic chambers and ageing chambers. The special ageing stand for simulating climate influences and testing of building materials is presented. The apparatus works as a rotational chamber for accelerated ageing. Samples are installed inside and are subjected to artificial climatic factors, such as: sun radiation, rain and low temperature. Moreover, the results of study on method for definition of simulated climate program in the aging chamber for an examplary are natural climate of Upper Region are commented. Additionally, the results of examplary aging and durability tests for noise barriers are presented.

PL

Artykuł prezentuje problematykę oceny trwałości materiałów i elementów budowlanych poddanych w czasie eksploatacji oddziaływaniom środowiska atmosferycznego, na podstawie testów laboratoryjnych wykorzystujących komory klimatyczne oraz komory starzeniowe. Przedstawiono klimatyczną komorę starzeniową do symulacji oddziaływań klimatycznych i testowania trwałości materiałów budowlanych. Skomentowano wyniki prac nad metodyką ustalania programu klimatu symulowanego w komorze starzeniowej dla przykładowego klimatu naturalnego Górnego Śląska. Ponadto przedstawiono wyniki przykładowych testów starzeniowych akustycznych ekranów drogowych wraz prognozą ich trwałości

3

Szacowanie trwałości wyrobów budowlanych eksponowanych na czynniki atmosferyczne metodą testów przyspieszonego starzenia

Bochen Jerzy

Zeszyty Naukowe Wyższej Szkoły Technicznej w Katowicach

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2011

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nr 3

5--18

4

Research, standardization and practice in accelerated ageing tests

Jakubowicz I.

Polimery

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2004

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T. 49, nr 5

321-326

EN

The increasing use of polymers in various technological environments requires understanding of the degradation phenomena and ultimately controlling them. Questions associated with performance, cost, durability and environmental effects are closely related to each other and must be answered before the industry and the consumers can adopt new materials. Often, the use of accelerated ageing tests constitutes the only possibility to produce measurable degradation and the desired materials assessment. However, prediction of service life, especially for materials expected to perform reliably for many decades, is a continuing challenge, which contains many pitfalls. In this paper, examples of the many years' work with accelerated ageing tests and lifetime predictions carried out at SP Swedish National Testing and Research Institute are used to demonstrate some problems and pitfalls that can be met with in practice. Some examples are also given on insufficient information in international standards for ageing tests. Special attention is given to prediction of service life with one data point only as well as the influence of different previous history, different environments and different evaluation methods on lifetime prediction. Other examples concern the use of high stress levels and physical depletion of stabilizers.

PL

W artykule o charakterze przeglądowym przedstawiono specyfikę badań przyspieszonego starzenia w porównaniu z odpowiednimi badaniami prowadzonymi w warunkach rzeczywistych. Podano matematyczne podstawy tej metody; sprowadzają się one do równań Arrheniusa. Przedyskutowano możliwość prognozowania czasu użytkowania badanego materiału na podstawie jednego pomiaru przyspieszonego starzenia (rys. 1, 2). Praktyczne przykłady zastosowania omawianej metody dotyczą trzech wariantów: (a) różniące się historią próbki tego samego materiału (rys. 3); (b) ten sam materiał, różne otoczenie (rys. 4); (c) ten sam materiał, odmienne metody oceny starzenia (rys. 5). Ponadto omówiono dwa istotne czynniki wpływające na wyniki przyspieszonego starzenia, mianowicie wysoki poziom naprężeń (czynnik ważny w badaniach kauczuków - rys. 6) oraz ubytek stabilizatorów w trakcie próby (rys. 7).