ChemInform Abstract: AN X-RAY PHOTOELECTRON SPECTROSCOPIC STUDY ON THE ROLE OF MOLYBDENUM IN INCREASING THE CORROSION RESISTANCE OF FERRITIC STAINLESS STEELS IN HYDROCHLORIC ACID

The role of a simultaneous additions of tungsten and tantalum on the anodic passivity of the passive films of the sputter-deposited nanocrystalline W-xTa alloys was studied using immersion tests, electrochemical measurements and X-ray photoelectron spectroscopic (XPS) analysis. The formation of spontaneous passive film on the alloys, which is composed of double oxyhydroxide of tungsten and tantalum ions are responsible for their higher corrosion resistance than those of the alloy-constituting elements in 12 M HCl solution open to air at 30°C. The quantitative surface analysis by XPS is clarified that the improved anodic passivity of the alloys than those of alloy-constituting elements is based on the formation of new anodic passive oxyhydroxide films composed of W6+ and Ta5+ ions. These films have higher protectiveness and stability than those of passive oxyhydroxide films of alloy-constituting elements, that is, oxyhydroxides of hexavalent tungsten and pentavalent tantalum after potentiostatic polarization for 1 h in 12 M HCl.DOI: http://dx.doi.org/10.3126/njst.v12i0.6492 Nepal Journal of Science and Technology 12 (2011) 139-148

Download Full-text

J & L TYPE 409/409 HP

Alloy Digest ◽

10.31399/asm.ad.ss0743 ◽

1999 ◽

Vol 48 (5) ◽

Keyword(s):

Corrosion Resistance ◽

Physical Properties ◽

Tensile Properties ◽

Stainless Steels ◽

Heat Treating ◽

Automotive Exhaust ◽

Ferritic Stainless Steels ◽

Resistance To Oxidation ◽

Specialty Steel ◽

Oxidation And Corrosion

Abstract J and L Types 409 HP are ferritic stainless steels with 11% chromium. They exhibit an excellent combination of good formability, economy, and resistance to oxidation and corrosion. It is typically used in automotive exhaust systems. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-743. Producer or source: J & L Specialty Steel Inc.

Download Full-text

MAGIVAL MG2

Alloy Digest ◽

10.31399/asm.ad.ss1161 ◽

2013 ◽

Vol 62 (11) ◽

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Coercive Force ◽

Magnetic Permeability ◽

Stainless Steels ◽

Heat Treating ◽

Steel Grade ◽

High Permeability ◽

Ferritic Stainless Steels ◽

Magnetic Applications

Abstract MAGIVAL MG2 is a free machining ferritic stainless steel grade with the same high machinability and corrosion resistance as type 430F, but offering a higher magnetic permeability and lower coercive force than MG1 (Alloy Digest SS-1159, October 2013). Magival is a group of easily workable ferritic stainless steels developed for magnetic applications where high permeability and low coercive force are required. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-1161. Producer or source: Valbruna Stainless Steel.

Download Full-text

Role of chromium in anomalous behaviour of the passive layer in Ni-Cr-Mo alloys in 1M HCl solution

CORROSION ◽

10.5006/3767 ◽

2022 ◽

Author(s):

Malvika Karri ◽

Amit Verma ◽

J.B. Singh ◽

Sunil Kumar Bonagani ◽

U.K. Goutam

Keyword(s):

Corrosion Resistance ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

Underlying Mechanism ◽

Passive Layer ◽

X Ray ◽

Superior Corrosion Resistance ◽

Hcl Solution ◽

Cr2o3 Layer

This work seeks to understand the underlying mechanism involved in passivity of Ni-Cr-Mo alloys in a less concentrated HCl solution (1M) by systematically varying contents of Cr and Mo solutes in model Ni-Cr-Mo alloys. Corrosion behaviour was evaluated based on potentiodynamic polarisation tests carried out in conjunction with electrochemical impedance and x-ray photoelectron spectroscopies of passive films that formed on alloys during their exposure to the HCl solution. Results have shown that an increase in Mo alone is not sufficient to improve the corrosion resistance of the alloys at lower concentrations of HCl. Optimum concentrations of Cr and Mo solutes have been found to be in the vicinity of ~17 wt.% Cr and ~19 wt.% Mo for superior corrosion resistance of the alloys. This was attributed to the protection of the Cr2O3 layer as a consequence of the enrichment of Mo6+ ions in the passive film in 1M HCl solution.

Download Full-text