Effect of strain ratio on hydrogen permeability properties of low carbon enamel steel

2021 ◽  
Vol 118 (4) ◽  
pp. 412
Author(s):  
Ramazan Uzun ◽  
Ümran Başkaya ◽  
Zafer Çetin ◽  
Yasemin Kılıç ◽  
Oğuz Gündüz ◽  
...  
Keyword(s):  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Strain Ratio ◽  
Optical Microscope ◽  
Low Carbon ◽  
Forming Process ◽  
Steel Material ◽  
Light Optical Microscope ◽  
Permeation Properties

In this study, the effect of varying strain levels on hydrogen permeability properties were investigated. Distinct strain levels (10% and 40%) were carried out on the deep drawing test samples by using Marciniak die to simulate the forming process. Amount of strain on deep drawn material was calculated by GOM’s ARAMIS 3D deformation measurement system. Hydrogen diffusion coefficient and permeation time were calculated by using Helios II system. Light optical microscope (LOM) and scanning electron microscopy (SEM) were used for microstructure characterization. Automated inclusion/precipitation analysis was performed by Thermoscientific Explorer-4. By this study, it is aimed to understand the hydrogen permeation properties of ultra-low carbon IF steel material with varying strain values. Finally, it was determined that number of inclusion/precipitation per mm2 was significantly increased as a function of strain ratio, which improves hydrogen permeation properties.

Temperature Dependence of Hydrogen Solubility and Diffusivity in Hydrogen Permeable Membrane of Pd-Cu Alloy with B2-Type Crystal Structure

2021 ◽  
Vol 407 ◽  
pp. 31-40
Author(s):  
Hiroshi Yukawa ◽  
Shimpei Watanabe ◽  
Asuka Suzuki ◽  
Yoshihisa Matsumoto ◽  
Hideki Araki ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Low Temperatures ◽  
Room Temperature ◽  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Hydrogen Flux ◽  
Cu Alloy ◽  
B2 Structure ◽  
Type Crystal

The temperature dependence of hydrogen solubility and diffusivity of Pd–53mol%Cu alloy membrane with the B2–type crystal structure has been investigated. The hydrogen permeation tests are performed using ultra–pure hydrogen (more than 9N) purified by a Pd–Ag alloy membrane to avoid any influences of impurities. It is found that the hydrogen permeability decreases significantly at low temperatures, especially near room temperature. The time dependence of hydrogen flux is monitored and found that the hydrogen flux decreases gradually during about 4 ~ 5 days after rapid cooling down to room temperature from 623 K.The results of the temperature dependence of the hydrogen permeability are analyzed in view of the consistent description of hydrogen permeation based on hydrogen chemical potential, where the hydrogen flux is proportional to the product of the mobility for hydrogen diffusion, B, and the PCT factor, fPCT. In this study, the pressure–composition–isotherms (PCT curves) for Pd–53Cu alloy with B2 structure are measured for the first time by the in–situ XRD–PCT method, and they are applied to estimate the PCT factors. Then, the temperature dependence of the PCT factor and the mobility for hydrogen diffusion is evaluated. It is revealed that the decrement in hydrogen permeability at low temperatures is mainly attributable to the decrement of the mobility for hydrogen diffusion.According to the positron annihilation experiments, the defects density is considered to be small in Pd–53Cu alloy with the B2 structure even at room temperature, suggesting that the excess Cu atoms in Pd–53Cu alloy occupy the positions of Pd sublattice, at which the Cu atoms form a local BCC–Cu unit. The diffusion of Cu atoms corresponds to the diffusion of BCC–Cu units in the B2 structure. Therefore the diffusion of Cu atoms and the configuration of BCC–Cu units in B2 structure could be a key to understand the gradual transition of hydrogen diffusivity at low temperatures.

Hydrogen in the Plastic Deformed Steel

2007 ◽  
Vol 537-538 ◽  
pp. 33-40 ◽  
Author(s):  
Enikö Réka Fábián ◽  
László Dévényi
Keyword(s):  
Cold Rolling ◽  
Room Temperature ◽  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Cold Work ◽  
Low Carbon ◽  
Steel Sheets ◽  
Metallic Inclusions ◽  
Dissolved Hydrogen ◽  
Grade Steel

The solubility of hydrogen in iron and steels are affected by temperature and crystal structure. At lower temperatures (below about 400°C), the excess hydrogen, beyond that which is soluble (and therefore dissolved) interstitially, is retained in the steel in other sites commonly referred to as ”traps”. At room temperature, the dissolved hydrogen may be only a small fraction of the total hydrogen content. The movement of hydrogen in steel occurs by the migration of atoms through the lattice. The hydrogen diffusion takes place with interstitial mechanism. Trapping enhances the solubility of hydrogen but decreases the diffusivity. In practice hydrogen transmissibility is characterized by TH value. We have studied the effect of the cold rolling on the TH value for Al-killed low carbon enamelling-grade steel sheets. The microstructures of the samples were formed from ferrite, carbides and some non-metallic inclusions. Reducing the thickness of the steel sheets by cold rolling in carbides appears ruptures, microcavities, and the dislocation density increases in ferrite grains. Cold work increases the hydrogen permeation time. The average of TH values after hot rolling was 0.6; after about 72 % thickness reductions by cold rolling the average TH values was 101.4.

Hydrogen Permeation Properties of Pd-Coated Ni37.5Nb27.5Zr25Co5Ta5 Amorphous Membrane

2010 ◽  
Vol 654-656 ◽  
pp. 2823-2826 ◽  
Author(s):  
Hong Seok Chin ◽  
Yu Chan Kim ◽  
Yoon Bae Kim ◽  
Jin Yoo Suh ◽  
Woo Young Lee ◽  
...  
Keyword(s):  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Permeation Properties

The hydrogen permeation properties of the Pd-coated Ni37.5Nb27.5Zr25Co5Ta5 amorphous membranes have been investigated at 673 and 723K for 720 hours (1 month). Values of the hydrogen permeability during these long term tests were found to be reduced of about 50 and 30 % at 673 and 723K, respectively. The reduction in the hydrogen permeability could be correlated to the change in the composition of the coating as well as at the interface between Pd coating and Ni-based amorphous membrane.

scholarly journals Hydrogen permeation properties of Pd-coated Pd33Ni52Si15 amorphous alloy membrane

2015 ◽  
Vol 33 (1) ◽  
pp. 56-58 ◽  
Author(s):  
Wojciech Prochwicz ◽  
Wojciech Macherzyński ◽  
Bogdan Paszkiewicz ◽  
Zdzisław M. Stępień
Keyword(s):  
Amorphous Alloy ◽  
Film Thickness ◽  
Potential Barrier ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Membrane Thickness ◽  
Dramatic Decrease ◽  
Hydrogen Flow ◽  
Flow Through ◽  
Permeation Properties

AbstractThe vast majority of experimental techniques used for the measurements of hydrogen permeability through metallic membranes whose one or both surfaces are covered with a thin Pd film is based on the assumption that a ratio of film-to-membrane thickness is small enough to cause hydrogen flow to be independent of the Pd film thickness. In an attempt to verify this assumption, we have measured the hydrogen flow through the Pd33Ni52Si15 amorphous membrane covered with Pd film of 10, 20, and 30 nm in thickness. Contrary to our expectations, we have found a dramatic decrease in hydrogen flow with the increase in Pd film thickness. Our findings are discussed in terms of potential barrier between the two different phases.

Alloying Effects on the Hydrogen Diffusivity during Hydrogen Permeation through Nb-Based Hydrogen Permeable Membranes

2010 ◽  
Vol 297-301 ◽  
pp. 1091-1096 ◽  
Author(s):  
Hiroshi Yukawa ◽  
G.X. Zhang ◽  
Masahiko Morinaga ◽  
T. Nambu ◽  
Yoshihisa Matsumoto
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Hydrogen Diffusivity ◽  
Hydrogen Flux ◽  
Pure Niobium ◽  
Hydrogen Diffusion Coefficient ◽  
Alloying Effects

The hydrogen solubility and the hydrogen permeability have been measured for Nb-based alloys in order to investigate the alloying effects on the hydrogen diffusivity during hydrogen permeation. The hydrogen diffusion coefficient during hydrogen permeation is estimated from a linear relationship between the normalized hydrogen flux, , and the difference of hydrogen concentration, C, between the inlet and the outlet sides of the membrane. It is found that the hydrogen diffusion coefficient during the hydrogen permeation is increased by alloying ruthenium or tungsten into niobium. On the other hand, the activation energy for hydrogen diffusion in pure niobium under the practical permeation condition is much higher than the reported values measured for dilute hydrogen solid solutions. It is interesting that the activation energy for hydrogen diffusion decreases by the addition of ruthenium or tungsten into niobium.

In Situ Analysis of Hydrogen Mobility during Hydrogen Permeation through Nb-Based Hydrogen Permeable Membranes

2011 ◽  
Vol 312-315 ◽  
pp. 506-512 ◽  
Author(s):  
Hiroshi Yukawa ◽  
T. Nambu ◽  
Yoshihisa Matsumoto
Keyword(s):  
Hydrogen Diffusion ◽  
Chemical Potential ◽  
Hydrogen Permeation ◽  
Hydrogen Permeability ◽  
Hydrogen Solubility ◽  
Hydrogen Flux ◽  
Pure Niobium ◽  
The Difference ◽  
Alloying Effects

The hydrogen solubility and the hydrogen permeability have been measured for Nb-based alloys in order to investigate the alloying effects on the hydrogen diffusivity during hydrogen permeation. It is found that the hydrogen solubility decreases by the addition of ruthenium, tungsten or molybdenum into niobium. The mobility for hydrogen diffusion during hydrogen permeation is estimated from the linear relationship between the normalized hydrogen flux, , and the product of the hydrogen concentration and the difference of hydrogen chemical potential, . It is found that the mobility for hydrogen diffusion during hydrogen permeation is larger for Nb-based alloys than pure niobium, especially at low temperature. The activation energy of the mobility for hydrogen diffusion decreases by the addition of ruthenium, tungsten or molybdenum into niobium.

Effect of Hydrogen Trapping and Poisons on Diffusion Behavior of Hydrogen in Low Carbon Steel

2018 ◽  
Vol 764 ◽  
pp. 3-10 ◽  
Author(s):  
Lian Cai ◽  
Li Min Zhao
Keyword(s):  
Carbon Steel ◽  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Diffusion Flux ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Hydrogen Trapping ◽  
Diffusion Behavior ◽  
Hydrogen Charging ◽  
And Diffusion

Effect of hydrogen trapping and poisons on diffusion behavior of hydrogen in commercial cold-rolled low carbon steel was investigated by means of electrochemical hydrogen permeation techniques. The experimental results reveal that diffusion rate and diffusion flux of hydrogen in the materials gradually increase with increasing the number of hydrogen charging and outgassing, and lag time significantly shortens with them, therefore, hydrogen trapping impede diffusion behavior of hydrogen in the materials. Different poisons in the hydrogen charging solution have also resulted in a certain influence on the assessment of hydrogen diffusion behavior.

Studies on Hydrogen Permeation of Weldments for Two Low-Alloyed Steels With Different Microstructures

2011 ◽  
Author(s):  
Jian Qun Tang ◽  
Jian Ming Gong
Keyword(s):  
Diffusion Coefficient ◽  
Hydrogen Diffusion ◽  
Hydrogen Permeation ◽  
Lath Martensite ◽  
Hydrogen Permeability ◽  
Diffusion Path ◽  
Permeation Rate ◽  
Liquefied Petroleum Gas ◽  
Boundary Area ◽  
And Diffusion

16MnR and SPV50Q low-alloyed steels, which have ferrite-pearlite and tempered martensite microstructures, respectively, are widely used to fabricate storage tanks for liquefied petroleum gas. However, during the process of operation, some cracks often occur on tanks made by these steels due to the presence of hydrogen, especially on weldments. The occurrence of this cracking is closely related to the diffusion and permeation of hydrogen in the steels. In order to explore the effect of different microstructures on hydrogen permeation and compare the hydrogen permeability of these two weldments, measurements were conducted on various metals (base metal-BM, heat-affected zone-HAZ, and welded metal-WM) cut from 16MnR and SPV50Q weldments by using electrochemical permeation tests. The results show that the microstructure has an important effect on hydrogen permeability. For 16MnR steel weldment, the diffusion coefficient of BM is the minimum due to the presence of the strong hydrogen traps in the interface between banded pearlite and matrix as well as the interface between inclusion and matrix. The microstructure of WM provides great grain boundary area as a hydrogen diffusion path and makes hydrogen easily diffuse, which results in the maximum permeation rate and diffusion coefficient. The fine-grained microstructure of normalized zone in HAZ acts as barriers for the hydrogen diffusion, which makes the permeation rate and diffusion coefficient of HAZ located between those of BM and WM. Similarly, for SPV50Q weldment, the permeation rate and diffusion coefficient increase in the order of BM, HAZ and WM. Those of BM are the minimum, which is correlated with the strong hydrogen trap due to the large quantities of dislocation within the lath martensite. Those of WM are the maximum for its strongly hydrogen diffusion path like WM of 16MnR weldment. As comparing the hydrogen permeability of 16MnR and SPV50Q weldment, the corresponding metals of the former always have greater permeation rate and diffusion coefficient than those of the latter, which is also due to its intrinsic microstructures.

Effect of Texture on Hydrogen Permeability in Low Carbon Al-Killed Steels

2010 ◽  
Vol 659 ◽  
pp. 301-306
Author(s):  
Fábián Enikő-Réka ◽  
Péter János Szabó
Keyword(s):  
Hydrogen Permeation ◽  
Electron Backscatter Diffraction ◽  
Hydrogen Permeability ◽  
Rolling Process ◽  
Fish Scale ◽  
Low Carbon ◽  
Steel Sheets ◽  
Backscatter Diffraction ◽  
Grade Steel

The susceptibility to fish-scale formation of cold rolled Al-killed low carbon enamel grade steel sheets is mainly determined by the hydrogen permeability. The role of the grain orientation in the hydrogen permeation time was investigated using scanning electron microscope based electron backscatter diffraction measurements. The fragmentations of massive cementite phase have a significant influence not only on the hydrogen permeability but also on the evolution of texture during the cold rolling process. Results showed that {111}[uvw] texture act as trapping site for hydrogen.

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