A. G. Tyurin

Thermodynamics of chemical and electrochemical stability of aluminum, silicon, and tin bronzes

Phase diagrams copper-element-oxygen and potential-pH diagrams are plotted for alloys of the Cu-Al, Cu-Si, and Cu-Sn systems at 25°C. Thermodynamic peculiarities of the corrosion and electrochemical behavior of phase components of aluminum, silicon, and tin bronzes are analyzed. The surface activity of alloying elements is assessed.

Thermodynamic Assessment of the Effect of Chromium and Molybdenum on the Passivability of Nickel-Base Alloys

The diagram of the Cr–Mo–O system, and the potential–pH diagrams of the Cr–Mo–H2O, NiCr15–H2O and NiCr15Mo15–H2O systems are constructed for 25°C. The thermodynamic peculiarities of the passivation of chromium–molybdenum, chromium–nickel, and nickel–chromium–molybdenum alloys are discussed.

Thermodynamics of chemical and electrochemical stability of brasses

Based on the theory of “regular” solutions, the thermodynamic properties of α-, β-, γ-, ɛ-, and η-phases of the Cu-Zn system are described. The surface activity of the elements in the phases is assessed. Potential-pH diagrams for the general system Cu-Zn-H2O and the manganese brass system H2O at 25°C are plotted. The nature of passivating films on conventional and special brasses and their composition are elucidated in different pH and potential ranges.

Estimation of the Effect of Molybdenum on Chemical and Electrochemical Stability of Iron-Based Alloys

The E–pH diagram of Mo–H2O system is refined. A cross-section of the Fe–Mo–O phase diagram at 25°C is constructed. The E–pH diagrams for the systems Fe–Mo–H2O and alloy X17H13M2–H2O are calculated. Thermodynamic aspect of the effect of molybdenum on chemical and electrochemical stability of iron alloys is discussed.

Thermodynamics of chemical and electrochemical stability of corrosion active nonmetal inclusions

Diagrams potential-pH are plotted for different phase components of corrosive nonmetal inclusions in steels in sulfide-containing media at 25°C, 1 atm (air), and ai = 10−3 mol/l. Thermodynamic peculiarities of their corrosion and electrochemical behavior are analyzed.

Thermodynamic analysis of the silicon effect on chemical and electrochemical stability of iron-chromium alloys

Phase diagrams Fe–Si–O and Cr–Si–O and potential–pH diagrams for the systems Fe–Si–H2O, Cr–Si–H2O, and alloy Fe + 25% Cr + 3% Si (α-phase)–H2O at 25°C are constructed. Thermodynamics of the silicon effect on the chemical and electrochemical stability of iron–chromium alloys is discussed.

The Diagram of Electrochemical Equilibrium of 12X18H10T Steel

Equilibrium potential–pH diagrams for the austenite of a 12X18H10T steel and possible second phases, such as titanium carbides TiC, Cr23C6-based M23C6 carbides, FeCr intermetallic compound (σ-phase) as well as silica and sulfide inclusions are considered. Concurrent effect of titanium, chromium, manganese, and silicon, on the chemical and electrochemical stability of stainless steel is discussed.

Diagrams of Electrochemical Equilibrium of M23C6 Type Carbides

Diagrams of electrochemical equilibrium of the Cr23C6–H2O, (Cr, Fe)23C6–H2O, (Cr, Fe, Mn)23C6–H2O, and (Cr, Fe, Mo)23C6–H2O systems at 25°C are constructed. Thermodynamic peculiarities of corrosion-electrochemical behavior of M23C6 type carbides are considered.