Mechanochemically Synthesis And The Spark Plasma Sintering Of The Niobium Carbide Nanoparticles

According to the method of mechanochemistry,high-energy ball milling was used totreat the mixture of niobium powder and1-octane,the powder after ball miling wassintered by the spark-plasma-sintering(SPS).Then the composition, phases and thevariation of powders after the high energy ball milling and the bulks sintered dealt withdifferent milling time were studied by XRD instrument, the variation of the displacementand shrinking rate of different ball milling had been analyzed; we had also analyzed thedensity of bulks by Archimedes law, the hardness of bulks sintered by a Vickers hardnesstester and the content of carbon and the toughness of the sample. At last, we discussed theoxidation and corrosion resistance of Nb2C/NbC.The results of XRD showed that with the action of high energy ball milling, we hadprepared a new materials-NbC successfully, the size of crystallite had reached thenanoscale.the particle size and grain size of original niobium powders had refined,thenon-crystallization tendency of Nb appeared after high energy ball milling.It was showed that we had successfully prepared the bulks of the NbC by the sparkplasma sintering；the densification of the samples during the sintering was completed in ashort period of time, the temperatures of shrinking increased by the ball milling time.The results of analysis showed that with the extension of the milling time, the carboncontent of prepared bulk had increased, so we found that the ball milling time can be usedto tune the ratio x of C/Nb，the density decreased and the hardness rose; The results of theDifferential Thermal Analysis (DTA) indicated that under570℃the oxidation resistanceof NbC is better than Nb2C’s,while above760℃the oxidation resistance of Nb2C is betterthan NbC’s.Studying on the electrochemical corrosion tests, we found that the corrosionresistance of the sample-NbC is better than the sample-Nb2C.