Current Trends in Integration of Nondestructive Testing Methods for Engineered Materials Testing

Material failure may occur in a variety of situations dependent on stress conditions, temperature, and internal or external load conditions. Many of the latest engineered materials combine several material types i.e., metals, carbon, glass, resins, adhesives, heterogeneous and nanomaterials (organic/inorganic) to produce multilayered, multifaceted structures that may fail in ductile, brittle, or both cases. Mechanical testing is a standard and basic component of any design and fabricating process. Mechanical testing also plays a vital role in maintaining cost-effectiveness in innovative advancement and predominance. Destructive tests include tensile testing, chemical analysis, hardness testing, fatigue testing, creep testing, shear testing, impact testing, stress rapture testing, fastener testing, residual stress measurement, and XRD. These tests can damage the molecular arrangement and even the microstructure of engineered materials. Nondestructive testing methods evaluate component/material/object quality without damaging the sample integrity. This review outlines advanced nondestructive techniques and explains predominantly used nondestructive techniques with respect to their applications, limitations, and advantages. The literature was further analyzed regarding experimental developments, data acquisition systems, and technologically upgraded accessory components. Additionally, the various combinations of methods applied for several types of material defects are reported. The ultimate goal of this review paper is to explain advanced nondestructive testing (NDT) techniques/tests, which are comprised of notable research work reporting evolved affordable systems with fast, precise, and repeatable systems with high accuracy for both experimental and data acquisition techniques. Furthermore, these advanced NDT approaches were assessed for their potential implementation at the industrial level for faster, more accurate, and secure operations.

Residual Properties in Damaged Laminated Composites through Nondestructive Testing: A Review

The development of damage tolerance strategies in the design of composite structures constitutes a major challenge for the widespread application of composite materials. Damage tolerance approaches require a proper combination of material behavior description and nondestructive techniques. In contrast to metals, strength degradation approaches, i.e., the residual strength in presence of cracks, are not straightforwardly enforceable in composites. The nonhomogeneous nature of such materials gives rise to several failure mechanisms and, therefore, the definition of an ultimate load carrying capacity is ambiguous. Nondestructive techniques are thus increasingly required, where the damage severity is quantified not only in terms of damage extension, but also in terms of material response of the damaged region. Based on different approaches, many nondestructive techniques have been proposed in the literature, which are able to provide a quantitative description of the material state. In the present paper, a review of such nondestructive techniques for laminated composites is presented. The main objective is to analyze the damage indexes related to each method and to point out their significance with respect to the residual mechanical performances, as a result of the working principle of each retained technique. A possible guide for future research on this subject is thus outlined.

On the use of ultrasonic guided waves for the health monitoring of rails

This paper deals with the health monitoring of rails. Many nondestructive techniques have been applied to rule on the health of rails. Ultrasonic guided waves (UGWs) technique is one among them. The current study focuses on this technique. First, it describes several kinds of defects that can occur in rails. Then, it presents the principle, advantages and limitations of UGW technique. The paper gathers as exhaustive as possible the previous works in which the said technique was used as a tool to monitor the health of rails. The paper put special emphasis on the use of UGW in structural health monitoring (SHM) context. In order to better understand the benefit/need of this technique in this context, by especially the non-specialist reader, a background concerning SHM is provided.

Ancient protein analysis in archaeology

The analysis of ancient proteins from paleontological, archeological, and historic materials is revealing insights into past subsistence practices, patterns of health and disease, evolution and phylogeny, and past environments. This review tracks the development of this field, discusses some of the major methodological strategies used, and synthesizes recent developments in archeological applications of ancient protein analysis. Moreover, this review highlights some of the challenges faced by the field and potential future directions, arguing that the development of minimally invasive or nondestructive techniques, strategies for protein authentication, and the integration of ancient protein analysis with other biomolecular techniques are important research strategies as this field grows.