The Experts below are selected from a list of 47304 Experts worldwide ranked by ideXlab platform
Jie-peng Zhang - One of the best experts on this subject based on the ideXlab platform.
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Novel Methods for Prevention of Hydrogen Embrittlement in Iron
Scientific Reports, 2017Co-Authors: Qiu Xu, Jie-peng ZhangAbstract:Iron is the most widely used metal in the world. However, hydrogen Embrittlement in steels—iron based alloys—is an important issue related to the safety of our infrastructure, such as railroads and bridges. Therefore, the prevention of hydrogen Embrittlement in steels is necessary. In the present study, we demonstrate two novel methods for the prevention of hydrogen Embrittlement in iron: one involves the low-energy implantation of helium, which is usually an element harmful to metals, into iron, the other is inducing damage to the iron surface by ion irradiation. In general, irradiation with high-energy particles leads to metal brittleness. In the former method, the driving force for hydrogen Embrittlement in iron is weakened, in the latter method, hydrogen diffusion in iron is prevented because of trapping of hydrogen atoms in the vacancies produced by the irradiation. As a result, hydrogen Embrittlement in iron was suppressed by both methods.
L. C. Lim - One of the best experts on this subject based on the ideXlab platform.
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Embrittlement of brazed martensitic stainless steel
Materials Science and Technology, 1998Co-Authors: G. K. L. Goh, L. C. LimAbstract:AbstractBrazing of AISI 410 martensitic stainless steel (12%Cr ) with boron containing nickel based filler metal was observed to lead to two major Embrittlement effects – temper Embrittlement and brazement Embrittlement. Temper Embrittlement, resulting from slow cooling of the material after brazing, affects both the dimple rupture and final brittle fracture portions of the impact energy of the. material. Brazement Embrittlement, resulting largely from the fine intra- and intergranular boride precipitates in the base metal adjacent to the braze, significantly limits the extent of dimple rupture before the onset of brittle fracture of the material under impact conditions. A simple analysis is presented which shows that the dimple rupture portion Ed and the brittle fracture portion Eb of the impact energy are affected differently by theabove Embrittlement mechanisms. Their order of significance is as follows: , where the double prime and si...
Rouholah Ashiri - One of the best experts on this subject based on the ideXlab platform.
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liquid metal Embrittlement free welds of zn coated twinning induced plasticity steels
Scripta Materialia, 2016Co-Authors: Rouholah Ashiri, M Shamanian, H R Salimijazi, Anwarul Haque, Changwook Ji, Kwanggeun Chin, Yeongdo ParkAbstract:Abstract The high electrical resistivity of twinning induced plasticity steels makes their resistance spot welding difficult and limits their weldability. Meanwhile, liquid metal Embrittlement of Zn-coated twinning induced plasticity steel welds is one of the most important challenges facing the scientific community. Liquid metal Embrittlement also limits weldability of the steels and influences the mechanical response of welds. This work addresses this challenge by developing an innovative pathway to obtain liquid metal Embrittlement-free welds which is able to extend the weldable current range of the steels. Simulations demonstrate that the method can perform a smart management of heating which is critically required to obtain Embrittlement-free welds.
Kenichi Takai - One of the best experts on this subject based on the ideXlab platform.
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dependence of hydrogen induced lattice defects and hydrogen Embrittlement of cold drawn pearlitic steels on hydrogen trap state temperature strain rate and hydrogen content
Acta Materialia, 2014Co-Authors: Tomoki Doshida, Kenichi TakaiAbstract:Abstract The effects of the hydrogen state, temperature, strain rate and hydrogen content on hydrogen Embrittlement susceptibility and hydrogen-induced lattice defects were evaluated for cold-drawn pearlitic steel that absorbed hydrogen in two trapping states. Firstly, tensile tests were carried out under various conditions to evaluate hydrogen Embrittlement susceptibility. The results showed that peak 2 hydrogen, desorbed at temperatures above 200 °C as determined by thermal desorption analysis (TDA), had no significant effect on hydrogen Embrittlement susceptibility. In contrast, hydrogen Embrittlement susceptibility increased in the presence of peak 1 hydrogen, desorbed from room temperature to 200 °C as determined by TDA, at temperatures higher than −30 °C, at lower strain rates and with higher hydrogen content. Next, the same effects on hydrogen-induced lattice defects were also evaluated by TDA using hydrogen as a probe. Peak 2 hydrogen showed no significant effect on either hydrogen-induced lattice defects or hydrogen Embrittlement susceptibility. It was found that hydrogen-induced lattice defects formed under the conditions where hydrogen Embrittlement susceptibility increased. This relationship indicates that hydrogen Embrittlement susceptibility was higher under the conditions where the formation of hydrogen-induced lattice defects tended to be enhanced. Since hydrogen-induced lattice defects formed by the interaction between hydrogen and strain were annihilated by annealing at a temperature of 200 °C, they were presumably vacancies or vacancy clusters. One of the common atomic-level changes that occur in cold-drawn pearlitic steel showing higher hydrogen Embrittlement susceptibility is the formation of vacancies and vacancy clusters.
Hidetoshi Fujii - One of the best experts on this subject based on the ideXlab platform.
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Improved resistance to hydrogen Embrittlement of friction stir welded high carbon steel plates
International Journal of Hydrogen Energy, 2015Co-Authors: Hidetoshi FujiiAbstract:Abstract The hydrogen Embrittlement of the friction stir welded high carbon steel plates was evaluated by the cathodic hydrogen charging method. The welding was performed below Ac1 transformation point and therefore the stir zone of the welds contained refined ferrite matrix distributed with cementite particles. After hydrogen charging for 4 h, large quantities of irreversible dome-shaped blisters were formed on the surface of the base metal. However, no blisters were observed in the stir zone even after charging for 16 h. In addition, hydrogen-induced internal cracks were formed throughout the thickness of the base metal. But the development of the internal cracks in the base metal was restricted when getting close to the stir zone. The hydrogen charged stir zone showed less reduction of ductility than the base metal during tensile testing, which reveals that the friction stir welded steel joints showed higher resistance to hydrogen embrittelment than base metal.
