Papers by Yuriy Yagodzinskyy
Hydrogen Uptake and Embrittlement Susceptibility of Ferrite-Pearlite Pipeline Steels
International Hydrogen Conference (IHC 2016): Materials Performance in Hydrogen Environments, 2017
Study on hydrogen embrittlement and dynamic strain ageing on low-alloy reactor pressure vessel steels
Journal of Nuclear Materials, Dec 1, 2021
Abstract Tensile tests in air with hydrogen pre-charged smooth specimens and slow strain rate tes... more Abstract Tensile tests in air with hydrogen pre-charged smooth specimens and slow strain rate tests with smooth and notched specimens in hydrogenated high-temperature water (HTW) at elevated temperatures (250−288 °C) on low-alloy reactor pressure vessel (RPV) steels revealed a softening in strength and a pronounced reduction in ductility, where the magnitude of hydrogen embrittlement (HE) increased with the dynamic strain ageing (DSA) susceptibility of the RPV steels. In hydrogen pre-charged specimens and in hydrogenated HTW, shear dominated transgranular fracture by microvoid coalescence with increasing amounts of macrovoids, quasi-cleavage regions and secondary cracking were observed. Thermal desorption spectroscopy showed an increase in the concentration of trapped hydrogen in high binding energy traps (vacancies & voids) induced by straining in DSA regime. The observed hydrogen effects on fracture behaviour is a consequence of plasticity localization resulting from the interaction between DSA and hydrogen. HESIV and HELP are the dominant HE mechanisms.
Hydrogen Effects on Material Behavior and Corrosion Deformation Interactions
Materials and Manufacturing Processes, 2016
Additive manufacturing (AM) is a rapidly growing field of technology. In order to increase the va... more Additive manufacturing (AM) is a rapidly growing field of technology. In order to increase the variety of metal alloys applicable for AM, selective laser melting (SLM) of duplex stainless steel 2205 powder and the resulting microstructure, density, mechanical properties, and corrosion resistance were investigated. An optimal set of processing parameters for producing high density (>99.9%) material was established. Various post-processing heat treatments were applied on the as-built predominantly ferritic material to achieve the desired dual-phase microstructure. Effects of annealing at temperatures of 950 °C, 1000 °C, 1050 °C, and 1100 °C on microstructure, crystallographic texture, and phase balance were examined. As a result of annealing, 40-46 vol.% of austenite phase was formed. Annealing decreased the high yield and tensile strength values of the as-built material, but significantly increased the ductility. Annealing also decreased the residual stresses in the material. Mechanical properties of the SLM-processed and heat-treated materials outperformed those of conventionally produced alloy counterparts. Using a scanning strategy with 66° rotation between layers decreased the strength of the crystallographic texture. Electrochemical cyclic potentiodynamic polarization testing in 0.6 M NaCl solution at room temperature showed that the heat treatment improved the pitting corrosion resistance of the as-built SLM-processed material.
Hydrogen-induced Strain Localization at Meso-scale in Austenitic Stainless Steels
Role of Excessive Vacancy Generated in p-n Type Duplex Cu2O Film under Anodic Bias in TGSCC of Pure Copper
Hydrogen effect of tensile properties of EUROFER 97 and ODS-EUROFER steels at elevated temperatures
Effect of Hydrogen on Plastic Deformation of Stable 18Cr-16Ni-10Mn Austenitic Stainless Steel Single Crystals
Nitrogen and Carbon Effects on Mechanisms of Reversion of Martensite to Austenite in Metastable AISI 301 Steel Grades and Their Hot Formability
Hydrogen-induced Cracking of Metastable Austenitic Stainless and High-Strength Carbon Steels
The European Corrosion Congress, EUROCORR 2011, September 4-8, 2011, Stockholm, Sweden
Mechanical Characterisation of Austenitic Stainless Steels and Inconel Alloys under Dynamic Strain Aging Conditions
Hydrogen-induced delayed fracture of high-strength carbon steels
Dynamic Strain Aging of Nuclear Power Plant Materials
Mechanical and Electrical Properties of CNT/copper Nanocomposites Processed by Hot Pressing
Comparative Study of Nitrogen and Carbon Effects on Mechanism of Reversion of a´ Martensite to Austenite in Metastable AISI 301 Steel Grades
Role of non-metallic inclusions in hydrogen-induced fracture of high-strength carbon steels
Effects of straining on oxide films and passivity of copper in nitrite solution at ambient temperature
Passivation of Metals and Semiconductors, and Properties of Thin Oxide Layers, 2006
Abstract The effects of strain rate on interactions between copper and its oxide films have been ... more Abstract The effects of strain rate on interactions between copper and its oxide films have been studied. The electrochemical oxidation process of copper is accompanied by the generation of vacancies in the copper substrate. Diffusion of vacancies from the oxide/metal interface or annihilation of vacancies by dislocation reactions is essential for oxidation to continue. Sufficiently slow straining without breaking the passive film on copper leads to a re-arrangement of the dislocation sub-structure at the interface, which helps to consume the oxidation-generated vacancies. The balance of slow straining and oxidation/dissolution produces environmentally-enhanced plasticity in the copper substrate, and simultaneously, accelerated corrosion. These conditions occur as long as the strain rate is low, i.e., on order of less than 10−8 s−1. The effects of slow straining on oxidation/dissolution of high purity copper were studied at various strain rates, even as low as 10−10 s−1. The electrochemical oxidation behaviour of cold-deformed copper was recorded by dynamic polarization scans. The synergistic effects of oxidation/dissolution process and straining on the mechanical properties of metal, i.e., dislocation sub-structure of copper were studied by TEM. The results are discussed in conjunction with a TGSCC model (SDVC, Selective Dissolution – Vacancy Creep). Central to the TGSCC model is the concept of vacancies generated in the process of oxidation/dissolution taking part in substrate recovery and playing a key role in the stress corrosion crack growth behaviour.
Hydrogen-enhanced creep and cracking of oxygen-free phosphorus-doped copper
Scripta Materialia, 2012
Hydrogen effects on the tensile properties of oxygen-free copper doped with 50 wt. ppm phosphorus... more Hydrogen effects on the tensile properties of oxygen-free copper doped with 50 wt. ppm phosphorus were studied under continuous electrochemical hydrogen charging. It was found that hydrogen reduces the tensile strength and uniform elongation of copper in slow strain rate tests. The copper manifests a remarkable sensitivity to hydrogen in constant load tests. It is found that hydrogen enhances the creep rate of copper. The creep rupture of copper with hydrogen manifests an intergranular dimpled fracture.
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Papers by Yuriy Yagodzinskyy