WANG Yanbin
,
WANG Anrong
,
CHU Wuyang
,
XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China associate professor
,
Department of Materials Physics
,
University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
The formation and aggravation of hydrogen damage in Fe-3 wt-% Si alloy during cathodic charging Were studied by means of Lange transmission X-ray topography.Results showed that hydrogen damage did not form in the specimens charged in 0.5 mol/L H_2S0_4 so- lution without poison,and occurred with addition of 250 mg/L As_2O_3 even at very low charge current density.As charging at a certain current density,the size of the damage may enlarge up to a limit yet no more by prolonged time.The damage size increased with increase of charging current density,but not so apparent at high current density. An external tensile stress could promote the formation of hydrogen damage obviously. It seems that for charging in H_2SO_4 solution containing poison,the drop of hydrogen permeation curve against time prolongation is due to the formation of hydrogen damages.
关键词:
hydrogen embrittlement
,
null
,
null
CHEN Niug
,
YU Zongsen University of Science and Technology Beijing
,
Beijing
,
China professor
,
Department of Materials Physics
,
University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
Si segregation was observed in the vacancy condensation pits,formed by supersaturated vacancies beneath the oxidation layer of Al-0.35wt-%Si alloy,by optical microscopy,X- ray photoelectron spectroscopy and microhardness tests.This phenomenon could only be explained by vacancy-Si complex inducing non-equilibrium segregation.
关键词:
non-equilibrium segregation
,
null
,
null
,
null
,
null
ZHANG Sanhong HE Xinlai CHU Youyi~* KE Jun University of Science and Technology Beijing
,
Beijing
,
China lecturer
,
Department of Materials Physics
,
University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
The behaviour of baron segregation at grain boundaries in Fe-3% Si has been studied by means of particle tracking autoradiography(PTA).The results indicate that the tendency of equilibrium segregation of B at grain boundaries in Fe-3% Si is higher than that in austenitic alloys.No observable nonequilibrium segregation of B at grain boundaries was revealed in Fe-3% Si alloy during cooling and isothermal holding.The binding energy between boron at- oms and grain boundaries is 55.7±1.7 kJ/mol.Based on the complex mechanism of B segre- gation of quenching-induce-nonequilibrium segregation,different behaviours of B segrega- tion in γ-Fe and bcc Fe-3% Si alloy were discussed.
关键词:
Boron
,
null
,
null
,
null