Bharat B.PANIGRAHI
,
N.Subba REDDY
,
Karabi DAS
材料科学技术（英文）
The effect of Al addition (2 and 5 at. pct) on sintering kinetics of Ti power was investigated. Al reduces the sintering rates, sinter density, increases activation energy of sintering and accelerates the grain growth. Sintering was controlled by mixed mode, i.e. transient liquid phase sintering, formation of intermetallics, and Ti grain boundary diffusion in TiAl2 and other intermetallics.
关键词:
Dilatometry
,
Sintering
,
Diffusion
,
Activati
B. Xu
材料科学技术（英文）
The effect of magnetic field on the growth behavior of compound layer was examined at the interface between the solid Cu and liquid Al during reactive diffusion. It was found that the thickness of compound layer was reduced by the high magnetic field. The growth activation energy in β, γ1 and "2 layers under a high magnetic field was larger than those in non magnetic circumstances, the increment percentage being 4.8%, 13.3% and 5.5%, respectively.
关键词:
Diffusion
B. Xu
材料科学技术（英文）
The effect of magnetic field on the growth behavior of compound layer was examined at the interface between the solid Cu and liquid Al during reactive diffusion. It was found that the thickness of compound layer was reduced by the high magnetic field. The growth activation energy in β, γ1 and "2 layers under a high magnetic field was larger than those in non magnetic circumstances, the increment percentage being 4.8%, 13.3% and 5.5%, respectively.
关键词:
Diffusion
Peng ZHANG
,
Yunhui DU
,
Shuming XING
,
Lizhong ZHANG
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
The bonding of steel plate to aluminum liquid was conducted using rapid solidification.The influence of diffusion time on interfacial structure was studied. The results showed that under the condition of 750ºC for the temperature of aluminum liquid and 200ºC for the preheat temperature of steel plate, when diffusion time was shorter than 4.3 s, there was only Fe-Al solid solution at the interface. When diffusion time was longer than 4.3 s, Fe-Al compound began to form at the interface. The relationships between diffusion time t and thickness of Fe-Al compound layer H are H=-9.72+2.62t-0.08t2 (4.3 s[t[15 s) and H=2.79+0.647t-0.033t2 (t>15 s).
关键词:
Diffusion
,
null
,
null
Fenghua LI
金属学报(英文版)
Dual titanium boride layers consisting of continuous TiB2 top-layer and TiB whisker sub- layer were formed on the surface of Ti6Al4V alloy using powder-pack boriding technique. An iso-thickness diagram of the whole boride layer was fitted with the data of thickness of the coating, treatment time and process temperature using Sigma Plot10.0 software. Growth kinetics of the titanium boride layer were analyzed by measuring the extent of penetration of TiB2 and TiB whisker as a function of boriding time in the range of 5-20 h and boriding temperature in the range of 1000 - 1100 ℃. By the linear regression analysis of growth kinetics of titanium boride layer, the diffusivity K and average diffusion activation energy (Q) of boron atoms in Ti6Al4V alloy were calculated, respectively.
关键词:
Boriding
,
固体粉末法
,
Ti6Al4V合金
,
动力学
,
扩散
Xiaotao LIU
,
Jianzhong CUI
,
Yanhui GUO
,
Xiaoming WU
,
Jun ZHANG
材料科学技术（英文）
The influence of an alternative magnetic field on the growth of the diffusion of Al and Mg in Al-Mg diffusion couple is studied. The diffusion zone is composed of two intermediate phases, namely β and γ phase. Thickness of each intermediate phase is examined. The results show that the alternative magnetic field increase the thicknesses of β and γ phase zone and the layer growth of β and γ phase obeys the parabolic rate law. The growth rate of the β and γ phase are increased with the application of the alternative magnetic field. This change is manifested through a change in the frequency factor k0 and not through a change in the activation energy Q. The frequency factor k0 for intermediate phase growth with an alternative magnetic field is 39.95 cm2/s for γ phase and 2.84×10-4 cm2/s for β phase compared with those without the magnetic field is 22.4 cm2/s for γ phase and 1.53×10-4 cm2/s for β phase.
关键词:
Alternative magnetic field
,
null
,
null
,
null
,
null
Zheng LIU
,
Ligang WANG
,
Lai WANG
材料科学技术（英文）
The microstructures, the changing rule of carbon-enriched zone, the diffusion behaviors of elements C and Cr, and the carbide type of 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints after aging at 500℃ for various times and after long-term service in technical practice were investigated by using the optical microscopy, electron probe microanalysis, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that in aging 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints, the main carbides are M3C and a few carbides are M7C3 and M23C6. The M3C carbide decomposition and dissolution with increasing aging time or aging temperature and the anti-diffusion of C and Cr cause the decrease and disappearance of the carbon-enriched zone. The results are different from those of the A302/1Cr5Mo dissimilar welded joints in previous studies.
关键词:
Dissimilar welded joint
,
null
,
null
,
null
Ximiao PAN
,
Zhanpeng JIN
材料科学技术（英文）
The phase equilibrium relations of the ternary Ni-Cr-Zr system at 900°C have been investigated by means of diffusion triple and electron probe microanalysis (EMPA) techniques. A series of tie lines and triangles have been determined, and the corresponding tentative isothermal section is presented based on the current information.
关键词:
Nickel
,
null
,
null
,
null
魏小荣
,
赵世金
上海金属
采用分子动力学模拟了Fe-1.95％ Cu-1.95％ Ni合金在823 K下的时效过程.结果表明:在Fe-Cu-Ni合金中,Cu和Ni之间存在一种相互促进扩散相互促进析出的协同作用；Cu、Ni的扩散过程都存在三个扩散速率不同的阶段,分别为自由迁移形成团簇的过程,溶质团簇的不断形成过程和团簇的长大过程.
关键词:
Fe-1.95％Cu-1.95％Ni合金
,
分子动力学模拟
,
时效
,
扩散
