冷却壁水管铸造过程中氧化渗碳及防护

针对高炉冷却壁的铸造过程,分析了此过程中冷却水管的渗碳和内表面的氧化机理及对冷却壁使用性能的影响．在此基础上概述、归纳了几种防护和消除的方法．     

冷却壁水管铸造过程中氧化渗碳及防护

针对高炉冷却壁的铸造过程,分析了此过程中冷却水管的渗碳和内表面的氧化机理及对冷却 壁使用性能的影响.在此基础上概述、归纳了几种防护和消除的方法.     

Superconducting Properties and Microstructure in MgB2 Bulks, Wires and Tapes

We prepared a series of MgB2 bulk samples under different temperatures, holding time and increasing rates in temperature by the solid state reaction. The thermodynamic behavior and phase formation in the Mg-B system were studied by using DTA, XRD and SEM. The results indicate that the formation of the MgB2 phase is very fast and the high increasing rate in temperature is necessary to obtain high quality MgB2. In addition, the effects of the Zr-doping in Mg1-xZrxB2 bulk samples fabricated by the solid state reaction at ambient pressure on phase compositions, microstructure and flux pinning behavior were investigated by using XRD, SQUID magnetometer, SEM and TEM. Critical current density Jc can be significantly enhanced by the Zr-doping and the best data are achieved in Mg0.9Zr0.1B2. For this sample, Jc values are remarkably improved to 1. 83 × 106 A/cm2 in self-field and 5. 51 × 105 A/cm2in 1T at 20K. Also, high quality MgB2/Ta/Cu wires and tapes with and without Ti-doping, MgB2/Fe wires and 18 filamen