贾皓张振强于湛邓康雷作胜任忠鸣
金属学报
doi:10.3724/SP.J.1037.2012.00093
通过物理模拟实验研究板坯连铸流动控制结晶器(flow control mold II, 即FC Mold II)电磁制动过程中, 磁场强度和分布对结晶器内金属液流动的影响规律. 实验中, 以水银为模拟工质, 在模型拉速为0.41, 0.52和0.82 m/min(分别相当于生产拉速1.00, 1.30和2.00 m/min), 电磁制动的上区磁场强度B1=0.18, 0.36和0.50 T, 下区磁场保持B2=0.50 T不变的匹配(组合)条件下, 考察结晶器(模型)内的水银流态和流速分布, 并以此分析上、下区磁场强度匹配(组合)对水口出流、液面流动以及结晶器窄面模壁所受冲刷等的影响规律. 结果表明, 在上述拉速条件下, FC Mold II电磁制动的上、下区磁场强度匹配关系, 分别取B1/B2=0.36, 0.72和1.00时, 结晶器中金属液的制动效果最好.
关键词:
板坯连铸
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FC Mold II
,
metal flow
,
electromagnetic braking
,
physical simulation
L. P. Karjalainen (Department of Mechanical Engineering
,
University of Oulu
,
Oulu
,
Finland)
金属学报(英文版)
Modelling has become a more and more valuable tool in the design, control and development of steel processing. Empirical regression equations, physically based approachs, artificial neural networks and hybrid models are being theied in computer modelling. In all cases, relevant data are necessary, which can be most economically obtained by physical simulation. Physical simulation with a Gleeble simulator has been used in a large number of tasks at the University of Oulu for ten years in cooperotion with the Finnish metals industry. Some examples of these will be described and discussed below, such as the optimization of the recrystallization controlled rolling process, the improvement of the hot strength model for the control of coiling tension and the optimization of continuous strip annealing schedules.Finally,brief remarks will be then on a couple of projects now under way.
关键词:
physical simulation
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null
,
null
,
null
,
null
L.P. Karjalainen
,
M.C. Somani
,
S.F. Medina
金属学报(英文版)
The analysis of numerous experimental equations published in the literature reveals a
wide scatter in the predictions for the static recrystallization kinetics of steels. The
powers of the deformation variables, strain and strain rate, similarly as the power
of the grain size vary in these equations. These differences are highlighted and the
typical values are compared between torsion and compression tests. Potential errors
in physical simulation testing are discussed.
关键词:
physical simulation
,
null
,
null
,
null
,
null
Z. Li
,
G.Q. Zhang
,
Z.H. Zhang
,
S.F. Tian
金属学报(英文版)
In order to evaluate the deformation characteristics of spray formed superalloy GH742
and determine the appropriate forging procedure of the alloy on this basis, the influence
of deformation temperature and strain rate on the ductility of spray formed GH742
was investigated by using the Gleeble-3500 thermal-mechanical testing machine. It is
shown that the forgeability of spray formed GH742 is better than conventional GH742
by ingot metallurgy because of refined grain structure and enhanced chemical homo-geneity of spray formed GH742. In the temperature range of 1020 to 1100℃, the
ductility of spray formed GH742 is dependent on the deformation temperature and is
increased linearly in proportion to the increment of deformation temperature, which
is more than 40% at 1020℃ and more than 60% at the temperature between 1100
and 1140℃. Furthermore, the results indicate the flow stress is affected considerably
by the deformation temperature and strain rate. In the temperature range of 1020 to
1140℃, the maximum flow stress of spray formed GH742 increases with the increment
of strain rate and decreases with the increment of the deformation temperature.
关键词:
spray forming
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null
,
null
,
null
L.H. Zhan
,
J. Zhong
,
X.Q. Li
,
M.H. Huang
金属学报(英文版)
A series of simulating experimental studies on the rheological behavior and its influential factors of aluminum alloy in continuous roll-casting process have been explored in this paper with a Gleeble-1500 Thermal-Mechanical Simulation Tester and a set of special clamp system. Relevant rheological rules in the process of coupling transient solidification and continuous deformation of roll-casting conditions are obtained. Experimental results indicate that four different characteristic stages exist in the whole rheological process, and relative constitutive models suitable for the given conditions of continuous roll casting process have been established through multivariable linear regression analysis of the experimental data.
关键词:
continuous roll-casting
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null
,
null
赵长亮
,
汪成义
,
孙彦辉
,
王正
,
沈宏俊
钢铁研究学报
doi:10.13228/j.boyuan.issn1001-0963.20140412
进行了300t脱磷转炉水模型实验,研究了8支底吹元件下不同底吹布置方式、底吹流量大小、顶吹参数、废钢加入比及不同废钢单重对熔池混合效果的影响.研究得出,当底吹元件集中对称布置在炉底0.42D圆周上,底吹供气强度达到2.94 m3/h,氧枪的枪位控制在58～88 mm之间时,熔池的混匀效果较好.通过熔池废钢加入的研究得出,当废钢比增加到10％时,熔池混匀时间值变化非常显著,不同单重废钢对熔池的混匀规律影响相似,在顶吹流量为30000 m3/h时,对于1.5t废钢单重,达到悬浮重量须满足底吹流量不小于4010 m3/h,研究结果可为实际操作工艺参数的优化提供参考依据.
关键词:
脱磷转炉
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物理模拟
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底吹布置
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混匀时间
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熔池废钢
宋剑锋
,
张文志
,
董永刚
材料科学与工艺
为了获得高温加工过程中41Cr4钢的动态再结晶体积百分数、真应力、真应变以及稳态应力和稳态应变,在不同变形温度、变形量和变形速度条件下,在GLEEBLE 3500试验机上完成了物理模拟试验.实验结果表明:变形刚开始时位错密度增大较快,因此应力迅速增大,产生加工硬化过程,随着应变的累积,动态回复的发生导致应力增加速度减慢,当应变进一步增大到超过临界应变时,动态再结晶软化导致流变应力降低.在此基础上建立41Cr4钢的流变应力模型时,考虑了加工硬化、动态再结晶以及动态回复对流变应力的影响,给出了与实验值比较接近的41Cr4钢的流变应力模型.
关键词:
流变应力
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物理模拟
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41Cr4钢
,
加工硬化
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动态回复
,
动态再结晶
赵福泽
,
朱绍珍
,
冯小辉
,
杨院生
材料工程
doi:10.11868/j.issn.1001-4381.2016.07.003
为研究高能超声处理制备纳米复合材料过程中纳米增强相在熔体中的分散过程，采用甘油为介质分别进行了数值模拟以及物理模拟。数值模拟结果表明，当超声作用于甘油中时，甘油中会形成中心-底面-壁面-中心的环形流动，变幅杆探头端面边缘附近甘油流体存在最大的流动速度，且随着超声功率的增大，流体运动速度增大。物理模拟实验结果显示，高能超声作用下甘油的实际运动行为与数值模拟结果相符合，存在环形流动；此外，高能超声作用下甘油中存在明显的空化效应；纳米晶须在超声作用下于甘油中分散良好，且随着超声功率的增大，达到充分分散所需时间变短。
关键词:
超声分散
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纳米晶须
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数值模拟
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物理模拟
李睿鑫
,
张浩
,
孔进丽
,
谢国柱
,
王青峰
,
王玉辉
钢铁研究学报
采用有限元方法对热压缩物理模拟过程进行了模拟，分析了接触静摩擦系数、形变量、应变速率对热压缩方向应变及应变速率均匀性的影响，对不同取样位置及分析方向的形变均匀性进行了分析，并观察相对应的原奥氏体晶粒，进行验证。结果表明，试样热压缩方向的应变及应变速率由心部向端部逐步减小，距试样中心1／4位置处最接近设定的应变及应变速率；接触静摩擦系数对试样热压缩方向形变不均匀性影响显著，形变量、应变速率对形变不均匀性的影响较小；推荐自热压方向1／4位置处取样，该处应变及应变速率基本符合设定条件，且形变均匀性最好。
关键词:
热压缩
,
物理模拟
,
形变不均匀性
,
有限元
,
再结晶
