Defining rejection limit of aluminium cast structures by stochastic methods. (October 2020)

• Record Type: Journal Article
• Authors: Narayanan, Govindarajan; Nackenhorst, Udo
• Is Part Of: Engineering failure analysis. Volume 116(2020)
• Publication Date: 2020-10
• Subjects: Stochastic process -- Fatigue life -- Cast aluminium alloy -- Bearing support structure -- Monte Carlo simulation; System failures (Engineering) -- Periodicals; Fracture mechanics -- Periodicals; Reliability (Engineering) -- Periodicals; Pannes -- Périodiques; Rupture, Mécanique de la -- Périodiques; Fiabilité -- Périodiques; Fracture mechanics; Reliability (Engineering); System failures (Engineering); Periodicals; Electronic journals; 620.112
• DOI: 10.1016/j.engfailanal.2020.104707
• Languages: English
• ISSNs: 1350-6307

Abstract

Highlight: Stochastic fatigue model to predict the casted aluminium structure's fatigue life is proposed. Accepting limit of the casted structure is simulated for quality criteria. Porosity simulation has been presented. Monte Carlo simulated fatigue data then compared with experimentally obtained fatigue life. Empirical fatigue life equation is derived. Abstract: Aluminium casting exceptionally an excellent candidate in replacing wrought structural components in various industries. The microstructure and defects introduced during the casting process must be then quantified for the strength requirements, particularly on their effect on fatigue performance either by experimental or modelling or by both. The quality of cast structure is also equally becoming pervasive, but it is yet elusive. The metal defects in the casting structure is mainly depends on solidification time, alloying element and standardized mould. The understanding of role of porosity on fatigue properties of cast structures is still outstanding. The analytical and empirical framework of stochastic assessment of fatigue life of aluminium cast structures is described in this paper not only to understand the stochastic nature of both fatigue and porosity but also to define the rejection limit on the cast aluminium structures based on established analytical fatigue limit for random porosity which is expected to be within the specified range. This paper describes the stochastic fatigue model for the purpose of defining the acceptable limit of the casting structures used in aero engine applications. Experimentally produced fatigue life is then compared with the data from stochastically generated fatigue life with good matching trend. The proposed stochastic fatigue model is then used to define the acceptance criteria on quality of casting.