王跃奎
,
杜挺
金属学报
Fe-Cu-Ce,Fe-P-Ce和Fe-Ti-Ce溶液的平衡产物是Ce_2O_2S,而不是Ce与Cu、P、Ti的金属间化合物。测定了Fe液中Ce_2O_2S=2[Ce]+[O]+2[S]反应的平衡常数和溶质之间的相互作用系数。Ce降低Cu和Ti在Fe液中的活度,增大其溶解度,同时增大P的活度,降低其溶解度。
关键词:
铁液
,
Ce
,
Cu
,
P
,
Ti
,
interaction
,
oxygen activity
陆跃华
,
刘纯鹏
金属学报
在1150—1250℃的范围内研究了Cu_2S与Cu_20交互反应的动力学,反应速率随Cu_2O颗粒表面积的增加而增加,温度的影响不明显。假设氧通过反应边界层液膜中的扩散是交互反应速率的控制步骤,最终动力学方程为 α=6.69×10~(-2)At (0<α<0.74) In(1-α)=-A(9.83×10~(-2)t+1.76)(0.74<α<1)
关键词:
Cu_2O
,
Cu_2S
,
interaction
,
kinetics
,
null
Caiyin YOU
材料科学技术（英）
Exchange interaction plays an important role on magnetic properties of nanocomposite magnets consisting of hard- and soft-magnetic phases. Here the exchange interaction in the Sm-Co/Co (and Fe65Co35) magnetic films was characterized by measuring static (mr(H)) and demagnetized (md(H)) remanence curves. According to conventional method: δm(H)=md(H)- [1- 2mr(H)], the exchange interaction was evaluated. The switching fields Hp′ and Hp, at which static (mr(H)) and demagnetized (md(H)) remanence show the fastest change, were identified. The relative ratio of switching fields H0p and Hp has a linear relationship with the maximum value δmmax of δm(H) curves, proposing an alternative way to characterize the exchange interaction.
关键词:
multi-layered films
,
films
,
exchange
,
interaction
贾文鹏
,
陈静
,
林鑫
,
钟诚文
,
黄卫东
金属学报
建立了激光快速成形过程中气/粉两相流送粉、激光熔覆成形温度场及粉末与熔池交互作用联合模型。采用有限单元生死技术模拟了熔覆层的沉积及熔池形成和自由界面形状演化，根据界面温度与粉末粒子动量损失模拟熔池对粒子的捕捉以及工件对粉末的反射，并采用朗格拉日方法实现了对粉末颗粒的跟踪。在此基础上，模拟了激光快速成形过程中316L不锈钢粉末、激光与熔池的交互作用过程，计算结果与实验相吻合。
关键词:
激光快速成形
,
melting pool
,
interaction
WANG Yuekui DU Ting Central Iron and Steel Research Institute
,
Ministry of Metallurgical Industry
,
Beijing
,
China
金属学报(英文版)
The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentified to be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibrium eonstant of Ce_2O_2S=2[Ce]+2[O]+[S] and the interaction coefficients between solutes in Fe-base solution have been determined as follows: K_(Ce_2O_2S)=2.57×10~(-5) e_(Ce)~(Cu)=-0.49;e_(Ce)~P=1.77;e_(Ce)~(Ti)=-3.62 e_(Cu)~(Ce)=-0.22;e_P~(Ce)=0.39;e_(Ti)~(Ce)=-1.23 ε_(Ce)~(Cu)=-128.0;ε_(Ce)~P=-224.1;ε_(Ce)~(Ti)=-710.0 Ce decreases the activities of Cu and Ti in Fe-base solution and increases their solubifities,as well as increases the activity of P and decreases its solubility.
关键词:
Fe-base solution
,
null
,
null
,
null
,
null
,
null
,
null
CHU Shuangjie
,
WANG Haowei
,
WU Renjie
,
LIN Xiaotang(Institute of Composite Materials
,
Shanghai Jiaotong University
,
Shanghai 200030
,
China) Manuscript received 9 May 1995
金属学报(英文版)
The interaction of particles with a solid-liquid interface during solidification of metal matrix composites has been investigated theoretically in this paper.Owing to the presence of particles in the melt,the shape of the solidification front and solute concentration field in front of solidification interface have been disturbed The thermodynamic method was employed,and a mathematical expression of the shape of the solidification interface and solute concentration field were deduced.Meanwhile,a theory is developed for evaluation of critical velocities of particles pushed by the solidification interface.A numerical simulation is done in which the critical velocity is evaluated as a function of particle size,thermal conductivity,diffusion coefficient,temperature gradient at the solidification front,the solid-liquid interfacial energy and the melt viscosity.The critical velocity is shown to be closely linked to the shape of the solidification interface and solute concentration field, and hence all the parameters also affect the shape of the solidification interface and solute concentration field of the front.
关键词:
:metal matrix composite
,
null
,
null
,
null
