The Experts below are selected from a list of 273 Experts worldwide ranked by ideXlab platform

Jiang Zhengyi - One of the best experts on this subject based on the ideXlab platform.

  • Effect of large load on the wear and corrosion behavior of high-strength EH47 Hull Steel in 3.5wt% NaCl solution with sand
    'Sociological Research Online', 2020
    Co-Authors: Zhang Hongmei, Li Yan, Yan Ling, Zhu Yangyang, Ai Fangfang, Jiang Zhengyi
    Abstract:

    © 2020, University of Science and Technology Beijing and Springer-Verlag GmbH Germany, part of Springer Nature. To simulate the wear and corrosion behavior of high-strength EH47 Hull Steel in a complicated marine environment in which seawater, sea ice, and sea sand coexist, accelerated wear and corrosion tests were performed in a laboratory setting using a tribometer. The effect of large loads on the behavior of abrasion and corrosion in a 3.5wt% NaCl solution with ice and sand to simulate a marine environment were investigated. The experimental results showed that the coefficient of friction (COF) decreases with increasing working load; meanwhile, the loading force and sand on the disk strongly influence the COF. The mechanisms of friction and the coupling effect of abrasion and corrosion in the 3.5wt% NaCl solution with sand were the wear and corrosion mechanisms; furthermore, the wear mechanism exerted the predominant effect

  • Influences of Load and Microstructure on Tribocorrosion Behaviour of High Strength Hull Steel in Saline Solution
    'Sociological Research Online', 2019
    Co-Authors: Wu Hui, Li Yan, Li Zhou, Cheng Xiawei, Hasan Mahadi, Zhang Hongmei, Jiang Zhengyi
    Abstract:

    The tribocorrosion behaviour of two diferent Hull Steels (namely, EH36 and EH47) was investigated using a ball-on-disk tribometer under varying normal loads from 10 to 100 N in a 3.5 wt% NaCl saline solution. Sliding in pure water was also performed for a comparison purpose. The results indicate that the corrosion products mainly consist of lath lepidocrocite (γ-FeOOH) with residual NaCl crystals when sliding against both Steels EH36 and EH47 in the saline solution. Tribocorrosion on EH36 (pearlitic Steel) shows lower coefcient of friction (COF) values than those obtained in water, while tribocorrosion on EH47 (bainitic Steel) leads to higher COF values instead. The former is due to the formation of considerable hydroxide particulates and flms with small sizes. In contrast, the latter is ascribed to the ploughing of hydroxides with smaller amounts and bigger sizes. In particular, the synergistic efects of corrosion and wear in tribocorrosion result in much higher total materials degradation, compared to that obtained through pure mechanical wear in water

  • The behaviour of tribocorrosion on EH47 high-strength ship Hull Steel in a 3.5% NaCl solution
    'Sociological Research Online', 2019
    Co-Authors: Zhang Hongmei, Li Yan, Yan Ling, Zhu Yangyang, Wang Changshun, Ai Fangfang, Jiang Zhengyi
    Abstract:

    © 2019 The Authors. In this paper, the tribocorrosion behaviour of EH 47 high-strength ship Hull Steel in a 3.5% NaCl solution was investigated. The tribological and corrosion tests were carried out on a Si3N4 ball-on-EH47 high-strength ship Hull Steel disc tribometer under different sliding time conditions. The disks were continuously immersed in sandy 3.5% NaCl solution during the whole process of the tribological tests. After the tribological tests, electrochemical tests were carried out to obtain typical polarization curves and electrochemical impedance spectroscopy diagrams. The corrosion experiments were performed to investigate the effect of abrasion on corrosion behaviour by immersing the samples in a container with 3.5% NaCl solution and 5 wt. % silica sand at room temperature for 7, 14, and 49 days. The micrographs, compositions and corrosion products of the worn scars were evaluated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) microanalyses

I. M. Robertson - One of the best experts on this subject based on the ideXlab platform.

  • Temper resistance of pressure Hull Steel microalloyed with niobium, titanium, and vanadium
    Materials Science and Technology, 1993
    Co-Authors: I. M. Robertson
    Abstract:

    AbstractThe role of microalloying additions (0·001–0·03 wt-%) to the quenched and tempered Steel ASTM A517 F has been examined. Steels with different levels of the microalloying elements were prepared and assessed via transmission electron microscopy and hardness loss during tempering. The extent of precipitation of the microalloys was also calculated using published expressions for the solubility of carbonitride phases. It was found that titanium is precipitated at high temperature and does not affect the temper resistance of the Steel. However, vanadium remains in solution at the austenitising temperature and has a significant effect on hardness loss during tempering. When niobium is also added, there is some precipitation in austenite with the titanium but the temper resistance is further increased.MST/1820

Huajian Liu - One of the best experts on this subject based on the ideXlab platform.

M. Z. Shah Khan - One of the best experts on this subject based on the ideXlab platform.

  • Influence of loading profile and superimposed flutter load frequency on the fracture behaviour of a submarine Hull Steel in seawater
    International Journal of Fatigue, 1993
    Co-Authors: M. Z. Shah Khan
    Abstract:

    Abstract Fracture surface examination is a useful approach in gaining an understanding of the fracture behaviour of materials. In this study the fracture surfaces of submarine Hull Steel specimens, which failed by corrosion fatigue in seawater, were examined in order to determine the micromechanics of the fracture process. Results show that the early stage of crack advance, corresponding to an approximate zone of 0.5 mm from crack initiation, was environment-controlled and independent of the loading profile and superimposed flutter load frequencies. Beyond this zone the influence of loading profile and superimposed flutter load frequency on the fracture morphology was clearly in evidence. The changes in the fracture morphology are described. The combinations of loading profile and superimposed flutte load frequency which influenced the cracking behaviour are identified. The influence of cracking modes on the overall fatigue life is also discussed.

  • S-N Behaviour and Flutter Load Frequency Effects on the Corrosion Fatigue Life of Submarine Hull Steels
    1993
    Co-Authors: M. Z. Shah Khan, I. A. Burch
    Abstract:

    A British experimental submarine Hull Steel, designated as RQT 701, was tested in seawater and under fatigue loading using a basic low frequency trapezoidal waveform and a superimposed flutter loading ranging in frequency between 1 Hz to 30 Hz. Similar test conditions were used in a previous investigation on the Australian submarine Hull Steel, BIS 812 EMA. Results showed that the fatigue life (S-N curve) of RQT 701 Steel was similar to that observed for the BIS 812 EMA Steel at a maximum cyclic stress of 753 MPa. At lower stress levels however, the fatigue life of RQT 701 Steel was marginally higher than the BIS 812 EMA Steel. When superimposed with flutter loading, both Steels showed similar fatigue lives in the frequency range of 1 Hz to 20 Hz. At 30 Hz however, RQT 701 Steel exhibited reduced fatigue life than that obtained for BIS 812 EMA Steel. In this work, fracture surfaces of specimens belonging to both Steels were examined and the micromechanics of fracture discussed and related to the observed fatigue life behaviour exhibited under superimposed flutter loads.

  • Effect of cyclic waveforms with superimposed high frequency flutter on the corrosion fatigue behaviour of a submarine Hull Steel
    International Journal of Fracture, 1991
    Co-Authors: M. Z. Shah Khan, I. A. Burch
    Abstract:

    Abstract : In the past, several investigators have reported changes in the stress corrosion fatigue behavior when small amplitude high frequency flutter loading was superimposed on a static load or the hold portion of cycle waveform. In a more recent study it was reported that in the presence of seawater the fatigue life (basic trapezoidal cycles) decreased when the superimposed flutter frequency increased from 1 Hz to 20 Hz. Above 20 Hz, and up to 30 Hz at least, no further frequency dependence was observed. The significance of the past findings are of considerable practical importance especially dealing with a new Steel (Australian designation BIS 812 EMA) for a submarine pressure Hull application.

Zhang Hongmei - One of the best experts on this subject based on the ideXlab platform.

  • Effect of large load on the wear and corrosion behavior of high-strength EH47 Hull Steel in 3.5wt% NaCl solution with sand
    'Sociological Research Online', 2020
    Co-Authors: Zhang Hongmei, Li Yan, Yan Ling, Zhu Yangyang, Ai Fangfang, Jiang Zhengyi
    Abstract:

    © 2020, University of Science and Technology Beijing and Springer-Verlag GmbH Germany, part of Springer Nature. To simulate the wear and corrosion behavior of high-strength EH47 Hull Steel in a complicated marine environment in which seawater, sea ice, and sea sand coexist, accelerated wear and corrosion tests were performed in a laboratory setting using a tribometer. The effect of large loads on the behavior of abrasion and corrosion in a 3.5wt% NaCl solution with ice and sand to simulate a marine environment were investigated. The experimental results showed that the coefficient of friction (COF) decreases with increasing working load; meanwhile, the loading force and sand on the disk strongly influence the COF. The mechanisms of friction and the coupling effect of abrasion and corrosion in the 3.5wt% NaCl solution with sand were the wear and corrosion mechanisms; furthermore, the wear mechanism exerted the predominant effect

  • Influences of Load and Microstructure on Tribocorrosion Behaviour of High Strength Hull Steel in Saline Solution
    'Sociological Research Online', 2019
    Co-Authors: Wu Hui, Li Yan, Li Zhou, Cheng Xiawei, Hasan Mahadi, Zhang Hongmei, Jiang Zhengyi
    Abstract:

    The tribocorrosion behaviour of two diferent Hull Steels (namely, EH36 and EH47) was investigated using a ball-on-disk tribometer under varying normal loads from 10 to 100 N in a 3.5 wt% NaCl saline solution. Sliding in pure water was also performed for a comparison purpose. The results indicate that the corrosion products mainly consist of lath lepidocrocite (γ-FeOOH) with residual NaCl crystals when sliding against both Steels EH36 and EH47 in the saline solution. Tribocorrosion on EH36 (pearlitic Steel) shows lower coefcient of friction (COF) values than those obtained in water, while tribocorrosion on EH47 (bainitic Steel) leads to higher COF values instead. The former is due to the formation of considerable hydroxide particulates and flms with small sizes. In contrast, the latter is ascribed to the ploughing of hydroxides with smaller amounts and bigger sizes. In particular, the synergistic efects of corrosion and wear in tribocorrosion result in much higher total materials degradation, compared to that obtained through pure mechanical wear in water

  • The behaviour of tribocorrosion on EH47 high-strength ship Hull Steel in a 3.5% NaCl solution
    'Sociological Research Online', 2019
    Co-Authors: Zhang Hongmei, Li Yan, Yan Ling, Zhu Yangyang, Wang Changshun, Ai Fangfang, Jiang Zhengyi
    Abstract:

    © 2019 The Authors. In this paper, the tribocorrosion behaviour of EH 47 high-strength ship Hull Steel in a 3.5% NaCl solution was investigated. The tribological and corrosion tests were carried out on a Si3N4 ball-on-EH47 high-strength ship Hull Steel disc tribometer under different sliding time conditions. The disks were continuously immersed in sandy 3.5% NaCl solution during the whole process of the tribological tests. After the tribological tests, electrochemical tests were carried out to obtain typical polarization curves and electrochemical impedance spectroscopy diagrams. The corrosion experiments were performed to investigate the effect of abrasion on corrosion behaviour by immersing the samples in a container with 3.5% NaCl solution and 5 wt. % silica sand at room temperature for 7, 14, and 49 days. The micrographs, compositions and corrosion products of the worn scars were evaluated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) microanalyses