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Article Citation - WoS: 1Citation - Scopus: 1Effect of Ti-V and Nb Addition on the Properties of Almg7cu1.2 Alloy(Springer Int Publ Ag, 2025) Gul, Armagan; Dispinar, Derya; Aslan, OzgurIn the development of aluminum casting alloys, considerable attention is given to the impact of various alloying elements, with numerous studies exploring how these elements influence the material's properties. However, the selection of alloying elements alone does not ensure optimal final quality. The casting process and melt treatment methods also play a critical role in achieving a defect-free structure, particularly when paired with defect characterization and final property assessment. Therefore, it is essential to investigate the interplay between alloying element choice, melt treatment, and defect evaluation in tandem. In this study, copper and magnesium main alloying elements have been chosen along with master alloys of Ti-V-Nb as grain refiners for the aluminum cast alloy. Phase formations have been investigated by simulated phase diagrams. Casting experiments have been done using a tilt pouring method into sand molds, and small bubble degassing equipment has been used to ensure the alloying and melt quality satisfying required mechanical strength. Composition and alloying have been validated by spectral analysis and XRF measurements. Microstructural analyses have been performed by both digital microscopy and scanning electron microscopy. EDS mappings have been carried out for alloying elements distributions. Internal defect distribution and defect structure have been evaluated by computed tomography (CT) scans. Both as-cast and heat-treated specimens have undergone tensile and hardness tests to characterize the mechanical behaviors. CT scans and mechanical behaviors have beencorrelated, and defect metrics have been investigated and classified according to defect surface, defect volumes and projected areas on XY-XZ-YZ planes. Contour maps of defect metrics and tensile properties have been analyzed to generate input to finite element simulations for latter stages studies, and correlation of strength-defect regressions has yielded parametric results to understand structural defects-mechanical performance relations. GTN and Beremin localization models capable of depicting material behavior in the presence of defects have been used to link the experimental and virtual validation assessments. In view of test results, a maximum of 0.125 wt% Nb content in AlMgCu-TiV alloy has been proposed having a tensile strength reaching 300 MPa-7.5% elongation at 0.75% Nb content with grain refinement effect owing to Al-Nb, Al-Ti, Al-V aluminide particles and good dispersion of Nb, Ti, V elements on the microstructure as assessed by EDS mapping. CT scan reconstruction images and metrics have successfully connected tensile strength and elongation with defect volume and defect surface area for the proposed alloy. In this context, the volume and surface area of defects have been evaluated as critical metrics in evaluating the mechanical properties of Al7MgCu1.2 cast alloys. Defect localization and failure point detection during plastic deformation zone have been demonstrated by Beremin model which can lead to future studies leveraging these metrics to validate material strength using damage models such as Gurson, GTN or Beremin for crack initiation and propagation methodologies.Article Relationship Between Crustal Magnetic Anomalies and Earthquake Activity in Malatya and Surrounding Region After the 2023 Kahramanmaraş Earthquakes, Southeastern Türkiye(Springer Int Publ Ag, 2026) Bilim, Funda; Kosaroglu, Sinan; Aydemir, AttilaThe East Anatolian Fault Zone (EAFZ) is one of the most critical and active tectonic elements in T & uuml;rkiye, and there are a significant number of high-magnitude earthquakes along with the EAFZ, mentioned in the historical documents and recorded in the instrumental periods in southeastern Anatolia. The latest devastating tectonic activity occurred on February 6, 2023 (Mw = 7.7), followed by another high-magnitude earthquake in the same day (Mw = 7.6) on this fault zone. More than 15,000 aftershocks (some of them are Mw >= 4.0) have been recorded since then. The EAFZ is composed of several sub-fault zones and their segments with different elongations. Although the majority of these segments indicate ruptures during the main shock and aftershocks, some of them (including the Malatya Fault) are still aseismic, including great potential to trigger high-magnitude earthquakes. In this study, we interpreted the magnetic data and the epicenter distributions of earthquakes to correlate the tectonic structures and active fault zones. The fault indicators (with maxspots) based on the different types of derivative transformations provided good correlations between the faults and magnetic discontinuities because almost all fault zones in the study area have been filled by the magmatic intrusions to create magnetic anomalies. The maxspots are also another practical tool to determine the possible segments of faults and/or exact locations of undefined magmatic intrusions. It is possible to claim that the faults have provided conduits for the intrusion of the causative bodies while triggering the earthquakes in this critical area. The earthquakes are generally recorded along the southern fault segments. As a result of these methods and correlations, we determined the exact location and the length of the Malatya Fault (approximately 220 km), which is represented with the low-magnitude earthquakes.
