Showing 3 results for Corrosion.
A. Ahmadi,, H. Sarpoolaky,, A. Mirhabibi, F. Golestani-Fard,
Volume 4, Issue 3 (12-2007)
Abstract
Abstract: Dolomite based refractories are widely used in Iranian steelmaking plants. In the
present research, wear and corrosion of refractories used in steel-making converter lining in
Esfahan Steel Company was studied. Post-mortem analysis of refractories clarified that the wear
started with oxidation of carbon followed by chemical corrosion. Iron oxide from slag reacted with
calcia, resulting in formation of low melting phase, and subsequent washout process, caused the
refractory corrosion onset from the hot face. In addition, the effect of aluminum as an anti-oxidant
and graphite on the corrosion resistance of refractory was investigated. Tar-dolomite samples
containing different amount of graphite (0, 4, 7, and 10 wt. %) were prepared in order to study
their physical properties, before and after coking. SEM micrographs employed to analyze the
microstructures to determine the effect of graphite and antioxidant on corrosion behavior of the
refractory. Results showed that oxidation process of carbon in the system was hindered and
improved corrosion resistance by introducing graphite and antioxidant into the refractory
composition.
Arash Yazdani, Mansour Soltanieh, Hossein Aghajani,
Volume 6, Issue 4 (12-2009)
Abstract
Abstract: In this research plasma nitriding of pure aluminium and effect of iron elemental alloy on the formation and growth of aluminium nitride was investigated. Also corrosion properties of formed AlN were investigated. After preparation, the samples were plasma nitrided at 550oC, for 6, 9 and 12 h and a gas mixture of 25%H2-75%N2. The microstructure and phases analysis were investigated using scanning electron microscopy and X-ray diffraction analysis. Moreover corrosion resistance of samples was investigated using polarization techniques. The results showed that only a compound layer was formed on the surface of samples and no diffusion zone was detected. Dominant phase in compound layer was AlN. Scanning electron microscopy results showed that nitride layer has particulate structure. These nitrided particles have grown columnar and perpendicular to the surface. It was also observed that the existence of iron in the samples increases the nitrogen diffusion, thus growth rate of iron containing nitrides are higher than the others. Corrosion tests results showed that formation of an aluminium nitride layer on the surface of aluminium decreases the corrosion resistance of aluminium significantly. This is due to elimination of surface oxide layer and propagation of cracks in the formed nitride layer
Gajanan M Naik, Santhosh Kumar B M, Shivakumar M M, Ramesh S, Maruthi Prashanth B H, Gajanan Anne6,
Volume 22, Issue 3 (9-2025)
Abstract
Magnesium and the alloys made from the same metal are utilized in the engineering applications such as automotive, marine, and aircraft, among others due to high strength to weight. Nevertheless, the applications of magnesium alloys are currently limited to a certain level due to their poor wear and corrosion properties. Another effective strategy for enhancing these properties involves utilizing the process of equal channel angular extrusion (ECAE), which serves to refine the grain structure, thereby resulting in improved material properties. This paper aims to establish the relationship between grain size reduction and wear and corrosion of AZ91 alloy. The wear performances of both coarse-grained and fine-grain alloy were conducted using L9 orthogonal array of experiments in order to study the effects of control parameters on wear performance. In the study, it has also been identified that through ECAP, the corrosion barrier and wear characteristics of the alloy were enhanced due to fine-grain-structure and the spheroidal precipitation of the second β-phase particles. Further, the influence of these changes on the performance of the AZ91 Mg alloy was assessed using SEM.
