From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and...From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation.展开更多
In the process of particle settling in a dilute,a density graded distribution of the liquid below the suspension needs to be designed according to the gravity of the suspension prior to sedimentation.In the present pa...In the process of particle settling in a dilute,a density graded distribution of the liquid below the suspension needs to be designed according to the gravity of the suspension prior to sedimentation.In the present paper a compositionally graded W-Mo composite was formed via the settling of the W and Mo particles,with a density gradient distributed in the initial clear liquid along the settling direction.展开更多
A new kind of method, co sedimentation method, was used to fabricate functional gradient material(FGM) in order to eliminate the interfaces in gradient materials. The deposit bodies obtained from the sedimentation of ...A new kind of method, co sedimentation method, was used to fabricate functional gradient material(FGM) in order to eliminate the interfaces in gradient materials. The deposit bodies obtained from the sedimentation of Ti and Mo particles were densified at 1 673 K under a pressure of 20 MPa in flowing argon for 1 h. Finally, Ti Mo system FGM with continuous change of composition was successfully prepared. The results reveal that the sedimentation method is an effective way to manufacture FGM with continuous change of composition. Moreover, the results also show that the compositional gradient of FGM can be adjusted in a wide range through both particle size distribution and the ratio of powders. [展开更多
A sedimentation method is proposed to fabricate functionally graded materials (FGMs) with the continuous andsmooth variations of composition. The relations between the compositional distribution of deposited body and ...A sedimentation method is proposed to fabricate functionally graded materials (FGMs) with the continuous andsmooth variations of composition. The relations between the compositional distribution of deposited body and thepowder characteristics of raw materials as well as settling parameters are derived. Subsequently, the mathematicalmodel of forming FGM based on the co-sedimentation has been established. At last, numerical simulations areconducted to explore the effects of the particle sizes of raw materials and suspension height on the compositionaldistribution of final products.展开更多
以金属共沉积理论为依据,对Cu2+、Ni2+共沉积进行计算,结果发现,理论计算值与实际工艺参数值之间存在极大差异。表明在化学沉积Ni Cu P合金过程中,由于Ni2+的重要作用———诱导在活性表面上放电及维持表面活性,使得Cu2+、Ni2+的共沉... 以金属共沉积理论为依据,对Cu2+、Ni2+共沉积进行计算,结果发现,理论计算值与实际工艺参数值之间存在极大差异。表明在化学沉积Ni Cu P合金过程中,由于Ni2+的重要作用———诱导在活性表面上放电及维持表面活性,使得Cu2+、Ni2+的共沉积不同于一般阴电极上金属共沉。展开更多
The manner by which the particles settle in the laminar flow region is first described and the characteristics of co sedimentation of two species particles are summarized.The subsequent introduction is focused on th...The manner by which the particles settle in the laminar flow region is first described and the characteristics of co sedimentation of two species particles are summarized.The subsequent introduction is focused on the fabrication process of continuously graded composites using co sedimentation technique.Finally,the authors point out the key problem that should be solved immediately,based on their current work.展开更多
文摘From the process of sedimentation the mathematical relationships among deposition Volume and powder properties as well as sedimentation parameters were deduced. Based on the formula a mathematical model was set up and simulated through the computer. At last the validity of mathematical model was supported by the representative experiment on Ti-Mo system FGM prepared by co-sedimentation.
文摘In the process of particle settling in a dilute,a density graded distribution of the liquid below the suspension needs to be designed according to the gravity of the suspension prior to sedimentation.In the present paper a compositionally graded W-Mo composite was formed via the settling of the W and Mo particles,with a density gradient distributed in the initial clear liquid along the settling direction.
文摘A new kind of method, co sedimentation method, was used to fabricate functional gradient material(FGM) in order to eliminate the interfaces in gradient materials. The deposit bodies obtained from the sedimentation of Ti and Mo particles were densified at 1 673 K under a pressure of 20 MPa in flowing argon for 1 h. Finally, Ti Mo system FGM with continuous change of composition was successfully prepared. The results reveal that the sedimentation method is an effective way to manufacture FGM with continuous change of composition. Moreover, the results also show that the compositional gradient of FGM can be adjusted in a wide range through both particle size distribution and the ratio of powders. [
基金This research is sponsored by the National Natural Science Foundation of China under grant No,50171049the Doctoral Science Foundation of Ministty of Education of China under the grant 1999049702.
文摘A sedimentation method is proposed to fabricate functionally graded materials (FGMs) with the continuous andsmooth variations of composition. The relations between the compositional distribution of deposited body and thepowder characteristics of raw materials as well as settling parameters are derived. Subsequently, the mathematicalmodel of forming FGM based on the co-sedimentation has been established. At last, numerical simulations areconducted to explore the effects of the particle sizes of raw materials and suspension height on the compositionaldistribution of final products.
基金FundedbytheNationalNaturalScienceFoundationofChi na (GrantNo.5 0 1710 4 9)
文摘The manner by which the particles settle in the laminar flow region is first described and the characteristics of co sedimentation of two species particles are summarized.The subsequent introduction is focused on the fabrication process of continuously graded composites using co sedimentation technique.Finally,the authors point out the key problem that should be solved immediately,based on their current work.
