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
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null
,
null
Peng ZHANG
,
Yunhui DU
,
Hanwu LIU
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
The pressing bonding of steel plate with QTi3.5-3.5graphite slurry was studied. The relationship among preheating temperature of steel plate, preheating temperature of dies, solid fraction of QTi3.5-3.5graphite slurry, and interfacial shear strength of bonding plate could be established with artificial neural networks perfectly. This model could be optimized with a genetic algorithm. The results show that the optimum bonding parameters are: 618℃ for preheating temperature of steel plate, 526℃ for preheating temperature of dies and 46.2% for solid fraction of QTi3.5-3.5graphite slurry, and the largest interfacial shear strength of bonding plate is 128.3 MPa.
关键词:
Steel-mushy QTi3.5-3.5graphite bonding
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null
,
null
Peng ZHANG
,
Yunhui DU
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
For the first time, the distribution of graphite particles in QTi3.5-3.5 graphite ingot was studied by using semi-solid casting technology. The results show that: the relationship between solid fraction and stirring temperature of QTi3.5-3.5 graphite slurry is y=759.4-0.711x (where y is solid fraction, x is stirring temperature). With the increasing of solid fraction of QTi3.5-3.5 graphite slurry, the agglomeration of graphite particles in ingot reduces gradually. The condition to prepare QTi3.5-3.5 graphite lubricant material with even distribution of graphite particles is that the solid fraction of QTi3.5-3.5 graphite slurry is larger than 40%.
关键词:
Peng ZHANG
,
Yunhui DU
,
Hanwu LIU
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
The electromagnetic-mechanical stirring technology was used to prepare QTi3.5-15/graghite slurry. The distribution of graphite particles in QTi3.5-15/graghite slurry was studied using cold quenching method. The results show that solid fraction of QTi3.5-15/graphite slurry increases with the decreasing of stirring temperature. There is a linear relationship between solid fraction and stirring temperature. With the increasing of solid fraction, the distribution of graphite particles in slurry becomes uniform gradually. When the solid fraction is larger than 45%, the rising of graphite particles in slurry can be restricted, and QTi3.5-15/graghite slurry with uniform distribution of graphite particles can be prepared.
关键词:
null
,
null
,
null
Peng ZHANG
,
Yunhui DU
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
The influence of solid fraction of AL-20Sn alloy mushy on gravity segregation of Sn in casting was studied and, the relationship between solid fraction and the temperature of alloy mushy and that between solid fraction of alloy mushy and size of Sn particle in ingot were determined. The results show that the relationship between solid fraction and the temperature of alloy mushy was f(s)=1683-4.86t+0.0035t(2). The extent of gravity segregation of Sn in casting reduced gradually with the increasing of solid fraction of alloy mushy. When solid fraction of alloy mushy was larger than 40%, the gravity segregation of Sn in casting could be removed basically, and the relationship between solid fraction of alloy mushy and size of Sn particle in ingot was s=-0.64f(s)+70.8.
关键词:
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
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null
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null
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null
,
null
Peng ZHANG
,
Yunhui DU
,
Hanwu LIU
,
Daben ZENG
,
Jianzhong CUI
,
Limin BA
材料科学技术（英文）
The rolling treatment of steel-mushy QTi3.5-3.5 graphite composite was conducted under different relative reduction at room temperature. The effect of room-temperature rolling on interfacial mechanical property of steel-mushy QTi3.5-3.5 graphite composite was studied and the relationship between interfacial shear strength and relative reduction was established. The results show that, for steel-mushy QTi3.5-3.5 graphite composite, which consists of 1.2 mm-thick 08Al steel plate and 2.8 mm-thick QTi3.5-3.5 graphite layer, there is a nonlinear relationship between interfacial shear strength and relative reduction in graphite layer. When relative reduction is smaller than 1.1%, interfacial shear strength increases with increasing the relative reduction. When relative reduction is larger than 1.1%, interfacial shear strength decreases with increasing the relative reduction. When relative reduction is 1.1%, the largest interfacial shear strength of 145.2 MPa can be obtained.
关键词:
Rolling
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null
,
null
,
null
Zhihao ZHAO
,
Jianzhong CUI
,
Jie DONG
,
Beijiang ZHANG
材料科学技术（英文）
The horizontal direct chill (HDC) casting process is a well-established production route for aluminum alloy ingot but the ingot may suffer from macrosegregation sometimes. In order to control the defect, a low frequency electromagnetic field has been applied in HDC casting process and the relevant influence has been studied. The results show that application of low frequency electromagnetic field can reduce macrosegregation in HDC casting process; and two main parameters of electromagnetic field density and frequency, have great influences on the solution distribution along the diameter of ingot. Moreover, the mechanisms of reduction of macrosegregation by electromagnetic field have been discussed.
关键词:
Low frequency electromagnetic field
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null
Peng ZHANG
,
Yunhui DU
,
Xueping REN
,
Limin BA
,
Hanwu LIU
,
Jianzhong CUI
材料科学技术（英文）
This paper studied the fractal characteristic of the interfacial shear surface of steel-Al solid to liquid bonding plate, and determined the relationship between fractal dimension and interfacial shear strength. The research results showed that the relationship between fractal dimension and interfacial shear strength could be described as y=26.2x+4.2 (where y was interfacial shear strength, x was fractal dimension) and when 08Al steel plate was coarsened by steel wire wheel which was made up with steel wires whose diameter were 1.4-1.6 mm, the optimum coarsening pattern of the steel plate surface could be got, the corresponding maximum interfacial shear surface fractal dimension of the bonding plate was 2.33, and the maximum interfacial shear strength of the bonding plate was 65.3 MPa.
关键词:
Furong CAO
,
Jianzhong CUI
,
Jinglin WEN
,
Fang LEI
材料科学技术（英文）
Mechanical properties and microstructure evolution of Mg-8.4 wt pet Li alloy have been investigated. The superplastic elongation-to-failure 920% at 573 K and initial strain rate of 5 x 10(-4) s(-1) at low nominal stress 2 MPa has been demonstrated. It was shown through optical microstructure that the average grain sizes at gauge length section before and after superplastic tension and at grip section were 7.5 mu m, 31.7 mu m and 20 mu m respectively, indicating significant deformation induced grain growth and static grain growth. Comparison of experiment data with published data for superplastic Mg-Li alloys shows that fine grain size and about 50 to 50 phase ratio contribute to achieving the largest superplasticity. Some related research works in other alloys are compiled and further evidences to such theoretic argument are provided.
关键词:
