Search

The present work reports our efforts to enhance the performance and uniformity for the long tapes of metal–organic deposition YBa2Cu3O7−x (MOD-YBCO) layer on ion-beam-assisted deposition MgO (IBAD-MgO) template. Reflection High-energy electron diffraction (RHEED) is employed to realize the in-situ growth monitor of IBAD-MgO, as well as the correlation between the quantitative RHEED peaks and in-plane texture of Epi-MgO identified by XRD, which is an effective guide to improve the uniformity and performance of long YBCO tapes. In addition, the surface of the LMO layer during the magnetron sputtering process is improved via controlling the O2 flux, and then the critical-current density (Jc) of YBCO films has been improved. By optimizing the texture of the MgO layer and precisely controlling the LMO layer growth conditions, the performance and uniformity of YBCO-coated conductors grown by metal–organic deposition (MOD) have been greatly enhanced. The superconducting current-carrying capacities of 12-mm-wide tapes have upgraded steadily from 400–500 A to 500–550 A in past 3 years. The laminated CC tapes with current-carrying capacities of 150–170 A per 4-mm width show good uniformity and high quality along 500-m length, implying being promising for various commercial power applications. [ABSTRACT FROM AUTHOR]

WS soft-coated tools were produced by medium-frequency magnetron sputtering, multi-arc ion plating, and ion beam-assisted deposition technique on the cemented carbide YT15 (WC + 15 % TiC + 6 % Co) substrates. The thickness, microhardness, surface morphologies, crystallization, and coating/substrate critical load of the coatings were tested and investigated. Dry turning tests on no. 45 quenched and tempered steel were carried out with the coated tool and uncoated YT15 tool. Cutting forces and cutting temperatures were tested, respectively. The result shows that the cutting force of WS soft-coated tool was decreased by 30-35 %, and the cutting temperature was reduced by 10-15 % in comparison with the uncoated YT15 tool. Through cutting force and cutting temperature theoretical analysis, the lower average shear strength of WS soft coating at the tool-chip and tool-workpiece interfaces leads to the decrease of cutting force and cutting temperature during cutting process. The advantage in cutting force and cutting temperature is obvious in relatively high-speed and high-temperature conditions may be because of the high temperature resistance and the oxidation resistance of WS soft coating which is not sensitive to high cutting temperature and high cutting speed. [ABSTRACT FROM AUTHOR]