Abridgment Of Nano And Micro Length Scale Mechanical Properties Of Novel Mg-9Li-7Al-1Sn And Mg-9Li-5Al-3Sn-1Zn Alloys Using Object Oriented Finite Element Modeling

In the recent years, magnesium-lithium (Mg-Li) alloys have attracted considerable attention/interest due to their high strength-to-density ratio and damping characteristic; and have found potential use in structural and biomedical applications. Here the mechanical behavior of novel Mg-9 wt.% Li-7 wt.% Al-1 wt.% Sn (LAT971) and Mg-9 wt.% Li-5 wt.% Al-3 wt.% Sn-1 wt.% Zn (LATZ9531) alloys is reported. Both, as cast and thermomechanically processed alloys have been studied which possess dual phase microstructure. Nanoindentation data have been utilized to envisage the elastic modulus of alloy via various micromechanics models (such as rule of mixtures, Voigt-Reuss, Cox model, Halpin-Tsai and Guth model) in order to estimate the elastic modulus. Object oriented finite element modeling (FEM) has been performed to predict stress distribution under tensile and compressive strain state. Close match between Halpin-Tsai model and FEM results show the abridgment of nano length scale property to evolution of microscopic stress distribution in novel LAT971 and LATZ9531 Mg-Li-Al based alloys

A Rare Case of Pulmonary Atresia with Ventricular Septal Defect with a Right Sided Aortic Arch and a Calcified Pulmonary AVM Presenting in an Adult without Cyanosis

Pulmonary atresia with ventricular septal defect (PA-VSD) with pulmonary arterial supply arising from the aorta representing large MAPCAs associated with a right sided aortic arch is an uncommon anomaly. Most of the patients succumb to severe respiratory compromise or congestive cardiac failure very early. We report the clinical details and imaging findings of a case of PA-VSD with a right sided aortic arch and a calcified pulmonary arteriovenous malformation (AVM) in a 21-year-old postpartum female with no previous episodes of cyanosis who was diagnosed as having a cardiac anomaly on echocardiography when she presented with breathlessness during the 8th month of the pregnancy