The paper presents a new type of twin-like objects observed in rolled pure magnesium. They have {1126} and {1122} habit planes and their misorientations to the matrix are close to 56˚ and 63˚ about 10 10  axis, respectively. The ad hoc performed theoretical analysis and atomic simulations allow to interpret the objects as {1012} {1012}  double twins formed by the simultaneous action of two twinning shears with completely re-twinned volume of primary twin. The observed inclinations from the ideal misorientations for such double twins can be explained by the compliance of the strain invariant condition in the twin boundary. It seems plausible that, once the double twin is formed, its twin boundaries are hard to move by glide of twinning disconnections. If so, these twins represent obstacles for the motion of crystal dislocations increasing the hardness of the metal.

Surface treatment of zinc galvanized steel is carried out usually using chromate based baths. These baths are used for improvement of the corrosion resistance and enhancement of the chemical adhesion of organic coatings. Anticorrosive effects of the chromium conversion coatings were not completely exceeded yet by another kind of passivation. Toxicity of CrVI is a basic problem of chromate conversion coats. This paper presents the main results and conclusions of experimental study on zinc conversion layers based on vanadates, using a good CrVI bath as reference. Anticorrosive mechanisms were compared by the corrosion tests in saline cabinet. Inhibition effects were characterized by scanning electron microscopy, by X-ray dispersive spectrometry (EDS) associated X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

A 3D reconstruction has been performed on a flat specimen after an interrupted in‐situ tensile tests. The sample consisted of austempered ductile cast iron (ADI) alloyed with 2.75% nickel. The analysis was performed by using a dual beam system (FIB‐SEM). The procedure of this analysis consisted in studying the elastic‐plastic behaviour along with the nucleation and the growing of cracks in ADI at room temperature. For this purpose, a field emission scanning electron microscope (FE‐SEM) equipped with a tensile stage was used. A systematic observation at the same location on the sample surface was used to clarify the tensile curves which are in agreement with deformation mechanisms. During the testing, decohesion of graphite nodules from the matrix was observed. The cracks initiated mainly at the interface of graphite nodule and the austenitic matrix. The elastic‐plastic region is connected with the plastic deformation of the matrix, growth and linking of microscopic cracks which are connected and finally leading to fracture of the sample.