材料期刊网

SURFACE STATE AND CATALYTIC ACTIVITY OF ACTIVATED AMORPHOUS Fe_(80)Zr_(12)B_8 ALLOY

WANG Xike SHEN Ningfu CHEN Haisong Zhengzhou Institute of Technology , Zhengzhou , ChinaZHANG Haifeng Luoyang Research Institute for Ship Materials , Luoyang , ChinaGU Haicheng Xi'an Jiaotong University , Xi'an , China Professor , Research Centre for Materials , Zhengzhou Institute of Technology , Zhengzhou 450002 , China

金属学报(英文版)

The depth profile of composition,chemical state of elements and morphology of as- received and activated amorphous Fe_(80)Zr_(12)B_8 alloy ribbons have been studied by means of Auger electron spectroscopy,X-ray photoelectron spectroscopy and scanning Auger microprobe combined with Ar ion bombardment.Both dull and free sides of the as- received ribbons were covered with an iron oxide layer.While a pronounced surface segregation and oxidation of B and precipitation of microcrystalline α-Fe particles were observed on both sides of activated ribbons,B and Zr were oxidized selectively in subsurface layer.On both sides of ribbons,a porous surface structure formed. The BET surface area was measured to be increasing from 0.11 to 2.68 m~2/g.The principal mechanism of in situ activation has been discussed.

关键词: amorphous Fe_(80)Zr_(12)B8 alloy , null , null , null

FATIGUE BEHAVIOUR OF M/B DUPLEX STRUCTURE IN A HIGH CARBON Cr-Mo-W STEEL

TIAN Baohong ZHENG Shi'an WU Lei Luoyang Institute of Technology , Luoyang , China ZHENG Shi'an , associate professor , Department of Materials Engineering , Luoyang Institute of Technology , Luoyang 471039 , China

金属学报(英文版)

Determination was carried out of fatigue crack propagation rate of steel 65Cr5Mo3W2VSiTi (LM2)with various bainite contents and M/B duplex structure tempered at various tempera- tures.The threshold value of fatigue for each processing was estimated by experimental data. The mechanism for fatigue crack propagation of M/B duplex structure in steel LM2 seems to be non-continuous.The calculated fatigue crack micro-propagation rates are found to agree with the experimental data.

关键词: duplex structure , null , null , null

TRACKING OBSERVATION ON SUBSURFACE CRACK IN BEARING STEEL GCr15 UNDER ROLLING CONTACT

CHEN Longqing Zhengzhou Institute of Technology , Zhengzhou , China CHEN Qing Luoyang Institute of Technology , Luoyang , China

金属学报(英文版)

Based on the sequent tracking observation on spalling of steel GCr15 under rolling contact fa- tigue,an expression for estimating the propagation of subsurface cracks was derived.The rol- ling contact fatigue life was found to be markedly related to the subsurface crack propagation angle.A new explanation of reason why the rolling contact fatigue life can be prolonged by residual compressive stress and retained austenite was advanced.

关键词: contact fatigue , null , null , null , null

INFLUENCE OF AUSTENITIZING TEMPERATURE ON IMPURITY SEGREGATION ALONG GRAIN BOUNDARIES IN STEEL 4330M

SHI Qunxing Luoyang Ship Material Research Institute , Luoyang , ChinaWU Jiansheng LIN Dongliang Shanghai Jiaotong University , Shanghai , China

金属学报(英文版)

The effect of austenitizing temperature on segregation of impurities along grain boundaries in steel 4330M has been examined by AES.The impurity segregation was computed quantitatively.Results showed that the quantity of impurity segregation changed with the austenitizing temperature.The limitation of the McLean′s expression for equilibrium segrega- tion was discussed.

关键词: steel 4330M , null , null , null

Mechanism of Work-hardening for Austenitic Manganese Steel under Non-severe Impact Loading Conditions

XIE Jingpei JIANG Qichuuan HE Zhenming LUO Quanshun K.Sommer ** Luoyang Institute of Technology , Luoyang , 471039 , China*** Stuttgart University , Germany+ To whom correspondence should be addressed

材料科学技术（英文）

The effect of C,Mn and heat-treatment on work-hardening of austenitic Mn steel and the work-hardening mechanism have been investigated under non-severe impact loading condition.The results show that the ability of work-hardening in- creases with the increase of C and aging tempera- ture but decreases with Mn.The work-hardening with high austenitic stability results mainly from dislocations,and that with low austenitic stability results mainly from combined effects of strain-in- duced martensite and high density of dislocations under non-severe impact loading conditions.The wear resistance of medium manganese steel (Mn7) is 1.64-2.46 times that of Hadfield steel (Mnl3).

关键词: austenitic manganese steel , null

EFFECT OF Al AND Si ADDITIVES ON CORROSION RESISTANCE OF Al_2O_3-C REFRACTORIES IN MOLD COVER FLUX

CHEN Zhaoyou TIAN Shouxin Luoyang Institute of Refractories Research , Ministry of Metallurgical Industry , Luoyang , China

金属学报(英文版)

Simulative study on corrosion of Al_2O_3-C refractories by mold cover flux has been carried out by means of immersion method.The results show that there fractory exhibits best resistance to the flux corrosion while the ratio of additive Al and Si is approximately equal to one.In addi- tion,ZrO_2-C specimens exhibit better corrosion resistance to mold cover.flux than Al_2O_3-C specimens.

关键词: refractoty , null , null , null

REVERSIBLE TRANSFORMATION BETWEEN MATRIX AND MARTENSITE IN Ni-Ti SHAPE MEMORY ALLOYS

LI Yan WU Yigui Luoyang Institute of Technology , Luoyang , ChinaHASHIMOTO Hatsujiro Okayama University of Science , Japan

金属学报(英文版)

The reversible transformation between matrix and martensite in Ni-Ti shape memory alloys has been dynamically observed under TEM.The orientation relation between martensite and austenite as well as the structural change near the transition temperature has been also studied with the help of HREM SADP.The results show that the orientation relation between martensite and austenite is[11]_A//[10]_M,[110]_A//[001]_M,(110)_A//(001)_M and the angle between(110)_A and(010)_M is about 6.5°.The crystal defects of martensite are found to be twin and stacking fault,and the twin plane as(100).

关键词: Ni-Ti alloy , null , null

Luoyang Institute of Refractories Research Ministry of Metallurgical Industry

ZHONG Xiangchong Luoyang Institute of Refractories Research , Luoyang , China.

材料科学技术（英文）

关键词:

EFFECT OF HIGH TEMPERATURE REPRESSING ON PHOSPHORUS SEGREGATION IN 93W-4.5Ni-2.5Fe ALLOY

LI Zhi XI Jukui YANG Yunlin Luoyang Institute of Technology , Luoyang , China

金属学报(英文版)

The influence of high temperature repressing treatment on the segregation of phosphorus in the 93W alloy was carefully investigated by means of Auger electron spectroscope,EPMA, TEM and SEM.The segregation of phosphorus has been observed at the tungsten-tungsten grain boundaries,particularly at the tungsten-matrix interphases when the specimens were kept at the temperature in the range of 1200—1500℃ ,followed by furnace cooling.However, no segregation of phosphorus was observed at the interfaces after the specimens were re- pressed at the range of temperature,followed by furnace cooling.After investigation,the dis- locations in the matrix phase of as-repressed specimens directly influenced the phosphorus segregation to the interfaces.After annealing,the mechanical properties were reduced because of the phosphorus segregation at the interface boundaries.

关键词: 93W-4.5Ni-2.5Fe alloy , null , null , null , null