In addition to manufacturing cost and production rates, damage resistance has become a major issue for the composites industry. Three-dimensional (3D) woven composites have superior through-thickness properties compared to two-dimensional (2D) laminates, for example, improved impact damage resistance, high interlaminar fracture toughness and reduced notch sensitivity. The performance of 3D woven preforms is dependent on the fabric architecture, which is determined by the binding pattern. For this study, angle interlock (AI) structures with through-thickness binding were manufactured. The AI cracking simulation shows that the transverse component is the one that leads to transverse matrix cracking in the weft yarn under tensile loading. Monitoring of acoustic emission (AE) during mechanical loading is an effective tool in the study of damage processes in glass fiber-reinforced composites. Tests were performed with piezoelectric sensors bonded on a tensile specimen acting as passive receivers of AE signals. An experimental data has been generated which was useful to validate the multi-physics finite element method (MP-FEM), providing insight into the damage behaviour of novel 3D AI glass fibre composites. MP-FEM and experimental data showed that transverse crack generated a predominant flexural mode A0 and also a less energetic extensional mode S0.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5512521 | PMC |
http://dx.doi.org/10.3390/ma9080699 | DOI Listing |
Materials (Basel)
December 2024
Department of Lifting and Transport Machines and Engineering of Port Technological Equipment, Odessa National Maritime University, 34, Mechnikova St., 65029 Odesa, Ukraine.
Evaluating the current technical condition and residual life of structures that may have reached or exceeded the end of their design life is a challenging issue in many industrial sectors. This paper focuses on the assessment of the structural integrity of structural elements of a seaport portal crane after operation for about 33 years. Test specimens were extracted from two crane elements, a jib (element A) as the most seriously loaded unit and, for comparison, a boom (element B) as the less loaded one, and machined in two different orientations, longitudinal and transversal.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Department of Mechanical Engineering, North Carolina A & T State University,1601 E. Market Street, Greensboro, NC 27411, USA.
Damage in composite laminates evolves through complex interactions of different failure modes, influenced by load type, environment, and initial damage, such as from transverse impact. This paper investigates damage growth in cross-ply polymeric matrix laminates under tensile load, focusing on three primary failure modes: transverse matrix cracks, delaminations, and fiber breaks in the primary loadbearing 0-degree laminae. Acoustic emission (AE) techniques can monitor and quantify damage in real time, provided the signals from these failure modes can be distinguished.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
December 2024
Aix Marseille Université, Université Gustave Eiffel, LBA, Marseille, France. Electronic address:
This study proposes a method for assessing the transverse toughness of human long-bone cortical tissue. The method is based on a three-point bending test of pre-notched femur diaphysis segments, post-processed using the compliance method coupled with numerical simulations. Given the cracking nature of bone and if cracking processes remain confined to the crack tip, it is assumed that the compliance method can be used.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
November 2024
School of Mechanical and Materials Engineering, University College Dublin, Dublin, Ireland. Electronic address:
The mechanical properties of the human skull have been examined and established previously in the literature, for example, the transversal isotropy of cranial bone and properties including the Elastic modulus and Poisson's ratio. However, despite the existing data, there are still mechanical properties which remain to be determined for the human skull. The present study aims to characterise the fracture properties of human cranial bone within the Linear Elastic Fracture Mechanics (LEFM) framework.
View Article and Find Full Text PDFData Brief
December 2024
Department of Civil and Environmental Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!