PSI - Issue 18

2

Staroverov O.A., Wildemann V.E., Tretyakov M.P., Yankin A.S./ Structural Integrity Procedia 00 (2019) 000–000

Staroverov Oleg A. et al. / Procedia Structural Integrity 18 (2019) 757–764

758

Peer-review under responsibility of the Gruppo Italiano Frattura (IGF) ExCo.

Keywords: Composites; tests; cyclic loads; fatigue sensitivity; low velocity shock loads; compression after impact; complex mechanical loads; postrcritical deformation.

1. Introduction Trends in the development of composite materials production technologies allow introducing composites into high forced parts and components of the space, aviation, and construction industries. With a constant increase in the resource reliability and safety of structures made of composite materials, the question of the creation and development of models of behavior and destruction of composite structures under complex cyclic, low-velocity loads arises. A review of modern scientific works shows that now there is no model that equally well considered both the type of impact (loading parameters) and the structure of materials (layouts of reinforcing layers). Each such damage accumulation model can only be used as a special case. Raeis Hosseiny, Jakobsen (2019), Samareh-Mousavi et al. (2019), Gao, An (2019), Hiremath et al. (2019), Roundi et al. (2019), Alam et al. (2019), Shabani et al. (2019), Khay et al. (2018), Kawai, Ishizuka (2018), Mostafa et al. (2018), Degrieck, Van Paepegem (2001), Hwang, Han (1986), Mao, Mahadevan (2002), Schaff, Davidson (1997), Subramanian et al. (1995), Ganesana, Joanna (2018). However, in some works, an attempt has been made to describe the behavior patterns of composites under various conditions. Suzuki et al. (2019), Wu et al. (2019), Chen et al. (2019), Barbu et al. (2019), Deveci, Artem (2018), Hack et al. (2018). In these studies, the authors often use the principle of linear summation of damage, without considering the loading history. Part of the work is aimed at describing various effects arising in the process of deformation and destruction of composites. Katunin (2018), Movahedi-Rad et al. (2019), Alves, Pimenta (2018), Ueki et al. (2018). These studies are based on methods of sharing test and diagnostic equipment, such as infrared thermos canning, recording of displacement and deformation fields and recording acoustic emission signals. Huang et al. (2019). Existing methods for predicting the elastic and strength characteristics of polymeric composite materials on the properties of components do not yet provide reliable results due to the difficulty of accounting for many significant factors. In most works, a direct method is used to assess the residual deformation and strength characteristics of materials. The authors note the staging of changes in the residual properties of composites under cyclic and subsequent quasi-static loads, which is associated with the processes of matrix cracking, local fiber breaks and delamination of material components. Strizhius (2016), Bey et al. (2015), Strizhius (2016), Kaminski et al. (2015), Van Paepegem, Degrieck (2001). Experimental work aimed at monitoring the processes of deformation and fracture using modern test equipment, allows to obtain new experimental data needed to verify the behavior patterns of composites under low-speed impact loads. Garcia-Castillo et al. (2014), Guillaud et al. (2015), Heimbs et al. (2014), Moallemzadeh et al. (2018), Lopresto et al. (2016). Most researchers use composite damage models for low-speed impact. The authors use a technique based on the application of a criterion for the destruction of a monolayer and the subsequent calculation of the material damageability considering the interaction of various damage evolution mechanisms. Saghafi et al. (2014), Riccio et al. (2014), Salvetti et al. (2016). This method is useful in designing but requires reliable experimental data. Studies aimed at studying low-velocity impact, including modeling of the process of deformation and fracture, supported by experimental data using non-destructive testing systems. Borrelli et al. (2014), Nikfar, Njuguna (2017), Caminero et al. (2018), Lemanle Sanga et al. (2018), Riccio et al. (2014), Voronov et al. (2018), Rivallant et al. (2014), Tan et al. (2015). The aim of the work was to study the laws of the mechanical behavior of polymer composite materials based on obtaining data on the processes of damage accumulation and destruction during complex static, cyclic and low-speed shock loads. 2. Material, experimental equipment and test methods The object of the study was samples of a composite material made according to serial technology based on prepreg fiberglass HPS-48 and a tie VSE 1212 with various reinforcement layouts [0/90] 8 , [±45] 8 , [0/30/0/60] 8 , autoclave