Effect of Niobium on Phase Transformations, Mechanical Properties and Corrosion of Supermartensitic Stainless Steel

Investigation on Dry Sliding Wear Performance and Corrosion Resistance of 13Cr5Ni2Mo Supermartensitic Stainless Steel

“…Only one peak, located at 2ϴ = 40.1° corresponds to (111) γ-austenite phase. The (200) γ, (220) γ, and (311) γ peaks are not visible because of their low intensity when compared to peak intensities of the α' martensite as this phenomenon has been encountered by several authors [10,13].…”

“…The latest process, repeated twice is called double tempering. The focus was (i) to permit the structural transformation into tempered martensite phase and to obtain the optimum combination between mechanical resistance, toughness, and elongation [10] (ii) to eliminate a maximum of residual stresses and best second phases (carbides) precipitations i.e. homogeneous distribution in all the volume.…”

Structural and Tribological Properties of Heat-Treated Stainless Steels against Abrasive and Lubricant Wear Conditions

“…It can be concluded that the heat treatment process for the Martensitic sample Sl led to the formation of the hardened martensitic phase, which is harder and more crystalline than the other retained austenitic phase initiated for the austenite stainless steel OS2 and OS3 samples after the heat treatment process. As illustrated in Figure 3, sample S1 has a predominantly bcc martensitic microstructure, with an average grain size of ≈8 µm, whereas the heat treatment process increased the grain size of the heat-treated grade OS1 to ≈42 µm due to the formation of the new tempered and more crystalline hardened martensitic phase, which is known for its high mechanical resistance, tensile nature, and toughness [7]. Meanwhile, the grain size of the untreated austenite sample S3 was ≈83.48µm, which was reduced to ≈58.64 µm for heat-treated samples OS3, owing to the formation of the weak and retained austenite phase after the heat treatment process.…”

“…Consequently, Martensitic stainless steel alloys are used to construct seamless tubes in oil or gas industries, industrial knives, oil pipelines and pumps, or other parts of machines suitable for the petroleum or agriculture instrumental industries [6]. The tribological wear conditions, such as the applied load, the speed velocity and surface topography of the moving parts, and the abrasion resulting from the hard surface and lubricant, provide an estimate of the optimal friction coefficient and wear resistance of the material under investigation [7]. Moreover, the average surface roughness belonging to the examined material affects the material's wear behaviour under lubricant conditions [8,9], and the adhesion contributes to the biocompatibility of the material [10].…”

Síntese e propriedades de materiais nanoestruturados luminescentes à base de Nb>sub<2>/sub<O>sub<5>/sub< e partículas SiO>sub<2>/sub<@Nb>sub<2>/sub<O>sub<5>/sub< dopados com íons lantanídeos para aplicação como marcadores ópticos

“…O nióbio é amplamente utilizado em indústrias eletrônicas e aeroespaciais, bem como na produção de aço e superligas (OLIVEIRA et al, 2016;DE OLIVEIRA et al, 2017). No âmbito geopolítico, apresenta um grande importância econômica para o Brasil, visto que não apenas possui 95,34% de suas reservas mundiais como também é responsável por 90% de sua produção mundial (U.S. Geological Survey -Mineral Commodity Summaries 2017).…”