The combined effects of direct current pulsed magnetic field (DC-PMF) and inoculation on pure aluminum were investigated, the grain refinement behavior of DC-PMF and inoculation was discussed. The experimental results indicate that the solidification micro structure of pure aluminum can be greatly refined under DC-PMF. Refinement of pure aluminum is attributed to electromagnetic undercooling and forced convection caused by DC-PMF. With single DC-PMF, the grain size in the equiaxed zone is uneven. However, under DC-PMF, by adding 0.05% (mass fraction) Al5Ti-B, the grain size of the sample is smaller, and the size distribution is more uniform than that of single DC-PMF. Furthermore, under the combination of DC-PMF and inoculation, with the increase of output current, the grain size is further reduced. When the output current increases to 100 A, the average grain size can decrease to 113 μn.
After the pyrogenation of carbon black and nanometer-sized iron catalyst at atmospheric pressure and a temperature of 1 100 ℃,new-diamond nanometer-particles were synthesized.The new-diamond was analyzed by X-ray diffraction(XRD).The lattice constant of the new-diamond is determined as 0.359 4 nm.Based on the ab initio principle of density functional theory,the electronic structure of the new-diamond was investigated.The results indicate that the new-diamond is a metallic form of carbon.