The NASGRO strip yield model predictions on fatigue crack growth for aircraft aluminium alloys under constant amplitude and variable amplitude programmed and random loading.

• Autorzy: Skorupa, M. , Machniewicz, T. , Skorupa, A.

Warianty tytułu

PL

Przewidywanie wzrostu pęknięć w lotniczych stopach aluminium przy stałoamplitudowych oraz programowanych i losowych zmiennoamplitudowych historiach obciążenia z użyciem modelu pasmowego płynięcia z pakietu NASGRO.

• Języki publikacji: EN

Abstrakty

EN

The strip yield model from the NASGRO computer software has been applied to predict fatigue crack growth in two different aircraft aluminium alloys under constant amplitude loading and programmed and random variable amplitude load histories. The computation options realized included either of the two different strip yield model implementations available in NASGRO and two types of the input material data description. The model performance has been evaluated based on comparisons between the predicted and observed results. It is concluded that altogether unsatisfactory prediction quality stems from an inadequate constraint factor conception incorporated in the NASGRO models.

PL

Model pasmowego płynięcia z pakietu NASGRO został zastosowany do prognozowania wzrostu pęknięć zmęczeniowych w dwóch lotniczych stopach aluminium, przy obciążeniach stałoamplitudowych oraz w warunkach programowanych i losowych zmiennoamplitudowych historii obciążeń. Weryfikowane opcje obliczeń uwzględniały użycie dwóch typów modeli pasmowego płynięcia dostępnych w pakiecie NASGRO, a także dwóch sposobów deklarowania wejściowych danych materiałowych. Oceny adekwatności modelu dokonano w oparciu o porównanie wyników przewidywanych i zaobserwowanych w trakcie badań zmęczeniowych. Stwierdzono, że niezadawalająca dokładność symulacji wynika głównie z niewłaściwej koncepcji kalibracji modelu NASGRO do danego materiału.

Słowa kluczowe

PL

wzrost pęknięć zmęczeniowych; model prognostyczny; stop aluminium

EN

fatigue crack growth; prediction models; aluminium alloys

• Czasopismo: Archive of Mechanical Engineering
• Rocznik: 2005
• Tom: Vol. LII, nr 4
• Strony: 361-391
• Opis fizyczny: Bibliogr. 25 poz., fig., tab.

Twórcy

autor

Skorupa, M.

• AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków, Poland,

autor

Machniewicz, T.

• AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Skorupa, A.

• AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków, Poland

Bibliografia

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