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The development of the ISD method has made it possible to deposit a film with in-plane alignment on a polycrystalline metal substrate and achieve a value ten times higher than normal PLD tape. We also confirmed that the resulting mechanical properties and other practical properties are improved. Since the ISD method can be used with metal substrates, which are inexpensive and easily made into long tape material, it is believed that it will be a very powerful method for future mass production.

The recent progress on the development of LPE process for fabricating coated conductors was reviewed. In order to prevent the reaction between liquid and metal, it was clarified that the combination of MgO or NiO buffer layer and MgO- or NiO-saturated liquid are both effective. There is difference in the influence of buffer material-addition to liquid for growth of the 1 LPE layer. Although the MgO addition affect little to the Y-solubility and of 123, NiO addition makes the able temperature range for Y123 growth decrease due to decrease of and increase of crystallization temperature of the low temperature phase. Additionally, it was found that the suitable selection of RE for each layers to suppress dissolution of the 1 layer at dipping for the 2 layer, which means stable growth of the 2 layer. Consequently, the double layered LPE structure successfully realized on metal substrates, which reveal high superconducting performance. Then, the suitable constructions for the LPE coated conductors were confirmed as that lower growth temperature for the 2 LPE layer should be selected than of the 1 LPE layer material. Additionally, a higher material than Y123 such as Nd- or Sm-system has to be selected for the 1 LPE layer in the NiO saturated system.

Next stage, the textured substrates such as the MgO deposited by using ISD technique or NiO fabricated by the SOE method will be applied to obtain high and . Furthermore, the process has to be extended to the long tape processing in parallel with improving and .

The development of the ISD method has made it possible to deposit a film with in-plane alignment on a polycrystalline metal substrate and achieve a value ten times higher than normal PLD tape. We also confirmed that the resulting mechanical properties and other practical properties are improved. Since the ISD method can be used with metal substrates, which are inexpensive and easily made into long tape material, it is believed that it will be a very powerful method for future mass production.

The development of the ISD method has made it possible to deposit a film with in-plane alignment on a polycrystalline metal substrate and achieve a value ten times higher than normal PLD tape. We also confirmed that the resulting mechanical properties and other practical properties are improved. Since the ISD method can be used with metal substrates, which are inexpensive and easily made into long tape material, it is believed that it will be a very powerful method for future mass production.

Solution deposition of coated conductors shows potential to be the lowest cost process toward workable coated conductors, but is confronted with several issues. Among these are the need for demonstration of high in multimicron thicknesses, and the need for scale-up of the crystallization anneal. While a value of 91 A/cm width has been obtained from a 6 layer, 0.7 MA/cm, 1.3 m diol-derived YBCO film, a method for fabricating yet thicker films of higher is certainly desired. It is hoped the delayed water introduction method, and improvements in crystallization kinetics will play a role in this development. Of key concern is development of a process to enable YBCO crystallization of layers greater than 0.3 m without significant -axis content; this remains an issue for both solution deposited and evaporated BaF process films. An additional area of concern is the scale-up of the crystallization anneal, and ability of the anneal to remove reaction products uniformly from the film. It is hoped that the parallel studies of evaporated BaF process film crystallization and scale-up will prove applicable to solution deposition due to the similarity of crystallization mechanisms in these processes.

The Combustion Chemical Vapor Deposition (CCVD) technique presents an attractive route for the deposition of low-cost, practical lengths of second-generation coated superconductors. CCVD-deposited buffer layers on textured nickel substrates have enabled high-performance superconductors of greater than 1 MA/cm. Thin films of YBCO deposited by CCVD exhibit excellent materials characteristics (epitaxy, composition, and microstructure) and electrical properties on single crystal substrates with critical current densities greater than 1MA/cm. The CCVD technology is very amenable to scale-up as has been demonstrated by the fabrication of 1 and 10 m lengths of buffered nickel. The incorporation of ccvd superconductor depositions can also be easily realized. Because of the inexpensive chemical and capital equipment costs, CCVD is well-positioned to fabricate commercial quantities of YBCO-coated conductor that meet DOE’s cost target of $10/kA-m.

The recent progress on the development of LPE process for fabricating coated conductors was reviewed. In order to prevent the reaction between liquid and metal, it was clarified that the combination of MgO or NiO buffer layer and MgO- or NiO-saturated liquid are both effective. There is difference in the influence of buffer material-addition to liquid for growth of the 1 LPE layer. Although the MgO addition affect little to the Y-solubility and of 123, NiO addition makes the able temperature range for Y123 growth decrease due to decrease of and increase of crystallization temperature of the low temperature phase. Additionally, it was found that the suitable selection of RE for each layers to suppress dissolution of the 1 layer at dipping for the 2 layer, which means stable growth of the 2 layer. Consequently, the double layered LPE structure successfully realized on metal substrates, which reveal high superconducting performance. Then, the suitable constructions for the LPE coated conductors were confirmed as that lower growth temperature for the 2 LPE layer should be selected than of the 1 LPE layer material. Additionally, a higher material than Y123 such as Nd- or Sm-system has to be selected for the 1 LPE layer in the NiO saturated system.

Next stage, the textured substrates such as the MgO deposited by using ISD technique or NiO fabricated by the SOE method will be applied to obtain high and . Furthermore, the process has to be extended to the long tape processing in parallel with improving and .

Pulsed Electron-beam Deposition (PED) is a relatively obscure but potentially a powerful technique for cost effective manufacturing of high temperature superconducting (HTS) films for Coated Conductor applications. This chapter is intended to introduce the reader to this novel deposition technique with a hope of creating sufficient interest among the coated conductor researchers, accelerating progress in this field. The PED technique is compared and contrasted with a popular and well established HTS deposition method, the Pulsed Laser Deposition (PLD). The detailed mechanism of the phenomena and all the features that contribute to the success of the PED technique are not clear at this point of time, reminiscent of the early stages of the historic trail of the evolution of PLD during the last 14 years. Several improvements are anticipated in the immediate future, both in the pulsed electron source performance and PED-based HTS process technologies to close the gap between the current research phase and the commercial scale-up stage. Rapid progress is expected, since the ‘technology road-map’ for coated conductors has already been established, with PLD as the fore-runner, identifying critical milestones that need to be realized, both from a cost and performance points of view. HTS films deposited on single crystalline substrates as well as textured RABiTS substrates have already indicated a film quality close to what is needed for practical applications. With its intrinsic cost-effectiveness, PED could very well become the deposition method of choice for high volume manufacturing of coated conductors.

The BaF process is a very attractive fabrication process for YBCO conductors since it allows the deposition and the formation steps of YBCO films to be separately performed, and it has been demonstrated that the films with high critical current densities can be fabricated on the buffered metallic substrates. However, we still face one major challenge for this process to be made as a commercially viable fabrication method. This is the avoidance of non--axis-oriented growth of YBCO when the thickness and the growth rates for the films are increased significantly beyond what are currently achieved. Meeting both the thickness and the growth-rate requirements simultaneously is extremely difficult. One possible way to make the rate requirement reduced is to find winding methods of the tapes in such ways that the both-sided tapes can be reacted in a batch process. Although the winding fixture will be more complicated than a simple dram, I believe that there are ways to construct such fixtures if the subatmospheric-pressure processing is incorporated in the design for reacting the wide precursor tapes. Then, we are only faced with the problem of growing the -axis-oriented thick YBCO films. In order to overcome the latter difficulty, we need a detailed understanding of the YBCO nucleation kinetics in thick films under various atmoshperic conditions. Such an understanding is likely to lead to the development of new or modified precursor-deposition methods and/or reaction-heat treatment procedures to facilitate the growth of the thick YBCO layers without the non--axis-oriented YBCO growth.

The development of the ISD method has made it possible to deposit a film with in-plane alignment on a polycrystalline metal substrate and achieve a value ten times higher than normal PLD tape. We also confirmed that the resulting mechanical properties and other practical properties are improved. Since the ISD method can be used with metal substrates, which are inexpensive and easily made into long tape material, it is believed that it will be a very powerful method for future mass production.