A Comparative Study to Evaluate the Essential Work of Fracture to Measure the Fracture Toughness of Quasi-Brittle Material

Abstract

In the present work, three different woven composite laminates were fabricated using the hand lay-up method. The woven reinforcement fibres were carbon fibres (CFRP), glass fibres (GFRP-W) and (GFRP-R) in combination with epoxy resin. Then, the central notch specimen tensile test (CNT) was used to measure the fracture toughness and the corresponding surface release energy (GIC). Then, the data were compared with the essential work of fracture (we) values based on the stored energy of the body to obtain a new standard fracture toughness test for composite laminates using relatively simple techniques. In addition to an extended finite element model, XFEM was implemented over a central notch specimen geometry to obtain a satisfactory validation of the essential work of fracture concepts. Therefore, the average values of (GIC) were measured with CNT specimens 25.15 kJ/m2, 32.5 kJ/m2 and 20.22 kJ/m2 for CFRP, GFRP-W and GFRP-R, respectively. The data are very close as the percentage error for the surface release energy measured by the two methods was 0.83, 4.6 and 5.16 for carbon, glass and random fibre composite laminates, respectively. The data for the fracture toughness of XFEM are also very close. The percentage error is 4.6, 5.25 and 2.95 for carbon, glass and random fibre composite laminates, respectively. Therefore, the fundamental work of the fracture concept is highly recommended as a fracture toughness test for composite laminates or quasi-brittle Material.

Fracture Performance Study of Carbon-Fiber-Reinforced Resin Matrix Composite Winding Layers under UV Aging Effect

“…When the influence region of a node is divided into two disjointed parts by a crack, the corresponding ghost node is activated. In Abaqus [36], the displacement vector around the crack in XFEM is expressed as:…”

Influence Parameters on the Essential Work of Fracture of 5754-H111 Aluminum Alloy Plate: Comparative Study

“…After a force is applied and the ligament fully yields, Eq. ( 2) for a DENT specimen can be rewritten as follows: (6) The mechanical energy in the elastic zone and the plastic energy utilized for necking and subsequent tearing, respectively, are denoted by Wy and Wpp, as shown in Fig. 2 a.…”

“…The assumption of a crack and the relationships among the length of the crack, the material's natural resistance to crack propagation and the stress at which the crack propagates rapidly to cause structural failure are made. Abdellah et al [6] applied a two fracture method, essential work of fracture method and compact tension test, using a two different thickness to investigate the surface energy JIC and the essential work of fracture for 5754-H111 aluminum alloy . He also created a straightforward finite element numerical model using the essential work of fracture (EWF) to forecast the parameters of EWF .Although the sample was measured in millimetres, the findings of the experiment and the suggested model were in good agreement.…”

Research on Energy Absorption Characteristics of Bouligand Biomimetic Structure Based on CFRP Composite Materials

“…CFRP laminates are composite materials composed of multiple layers of carbon fiber fabric or prepreg. They are formed by stacking multiple layers of carbon fiber fabric with resin layers and undergoing curing and heating processes [30][31][32][33]. CFRP laminates are processed by vacuum-assisted molding, where single layers of fiber sheets are overlaid at specific angles.…”

“…Commonly used lamination angles include 0 • , 45 • , and 90 • [32,33,35,37]. In addition to these common angles, other angles can be selected to meet specific requirements.…”