A5013885717- Hydrogen embrittlement and corrosion behaviors in metals
- Corrosion Behavior and Inhibition
- Nuclear Materials and Properties
- Microstructure and Mechanical Properties of Steels
- Material Properties and Failure Mechanisms
- Fatigue and fracture mechanics
- Welding Techniques and Residual Stresses
- High Temperature Alloys and Creep
- Additive Manufacturing Materials and Processes
- Metal and Thin Film Mechanics
- Titanium Alloys Microstructure and Properties
- Metal Alloys Wear and Properties
- Non-Destructive Testing Techniques
- High Entropy Alloys Studies
- Aluminum Alloys Composites Properties
- Magnesium Alloys: Properties and Applications
- Mechanical Failure Analysis and Simulation
- Electrocatalysts for Energy Conversion
- Advanced materials and composites
Imperial College London
2021-2024
University of Oxford
2024
Universidad de Oviedo
2017-2022
The study of steels which guarantee safety and reliability throughout their service life in hydrogen-rich environments has increased considerably recent years. Their mechanical behavior terms hydrogen embrittlement is utmost importance. This work aims to assess the effects on tensile properties quenched tempered 42CrMo4 steels. Tensile tests were performed smooth notched specimens under different conditions: pre-charged high pressure gas, electrochemically pre-charged, in-situ charged an...
We investigate the implications of conducting hydrogen-assisted fatigue crack growth experiments in a hydrogen gas environment (in-situ charging) or air (following exposure to gas). The study is conducted on welded 42CrMo4 steel, primary candidate for future transport infrastructure, allowing us additionally gain insight into differences behavior between base steel and coarse grain heat affected zone. results reveal significant two testing approaches weld regions. are particularly remarkable...
Abstract Hydrogen embrittlement (HE) is a major issue for the mechanical integrity of high-strength alloys exposed to hydrogen-rich environments, with diffusion and trapping hydrogen being critical phenomena. Here, role microstructure on diffusion, in additively manufactured (AM) wrought Inconel 718 compared, revealing key played by dislocation cells. Trapping behaviour hydrogen-saturated analysed thermal desorption spectroscopy numerical simulations. A high density traps cell walls,...
The influence of hydrogen on the mechanical properties three structural steels has been evaluated. A testing procedure based Small Punch Test with notched specimens was used to measure embrittlement. Two pre-charging methods were applied introduce in samples. first method gaseous a high-pressure reactor at 19.5 MPa and 450 °C for 21 h. second involved cathodic charging from 2 M H2SO4 + As2O3 electrolyte current density mA/cm2. results obtained Tests compared those using standard fracture...
The relative efficacy of electrochemical permeation (EP) and isothermal desorption spectroscopy (ITDS) methods for determining the hydrogen diffusivity is investigated using cold-rolled pure iron. diffusivities determined from 13 first transient 8 second EP experiments, evaluated conventional lag breakthrough time methods, are compared to results 10 ITDS experiments. Results demonstrate that average similar between ITDS, which distinctly increased transient. However, coefficient variation...
42CrMo4 steel was submitted to annealing, normalizing, and quench tempering heat treatments produce microstructures with different hardness levels. Afterwards, tensile tests using notched specimens were conducted in air two hydrogenated conditions by means of in-situ electrochemical hydrogen charging tests. Two electrolytes density currents employed low high conditions. The influence microstructure on embrittlement determined scanning electron microscopy (SEM) analysis used identify the...
We use a unique combination of electrochemical techniques to elucidate the dependency hydrogen evolution reaction (HER) and absorption on pH overpotential for iron nickel. Impedance spectroscopy shows dominance Volmer–Heyrovsky pathway, challenging common consideration Volmer–Tafel dominance. Polarization slopes agree with Volmer or Heyrovsky rate-determining step, limitations at high overpotential. The steady-state permeation current density is rationalized through newly-developed theory....
The effect of internal hydrogen in the fatigue crack growth rate coarse grain region a 2.25Cr1Mo steel welded joint was analyzed this work. microstructure simulated by means heat treatment able to provide same with similar prior austenite size and hardness one real joint. measured under standard laboratory conditions using compact tensile (CT) specimens that were (i) uncharged pre-charged pressure reactor (under 19.5 MPa 450 °C for 21 h). influence frequency assessed frequencies 10 Hz, 0.1...
High alloy white cast irons (WCI) play an important role in many industrial fields such as mining, cement industry, or grinding due to their high hardness and wear resistance. In all these processes, iron components must work under erosion abrasion conditions. Many investigations have been carried out with the aim of improving mechanical properties this type alloys. Wear resistance depends on properties, mainly hardness. Thus, WCI are typically heat treated order modify its microstructure,...