Study on Accelerating Mechanism of Nickel during Synthesis of Tungsten Carbide

The mixed powder of W, active carbon and Ni is ball milled and the resultants are analyzed by means of XRD, SEM and chemical analysis.The results show that WC can be synthesized under the condition of the content of Ni is 5%, the volume ratio of ball and material is 50:1 after 50 hours milling, or under the condition of the content of Ni is 5%, the volume ratio of ball and material is 30:1 after 100 hours milling, while there will be plenty of unreacted W and C left even after 50 hours milling in case of absence of Ni, indicating that Ni can shorten synthesis time of WC, increase reaction velocity.This may be attributed to plenty of Ni centric micro-gathering agglomerates which increase the contact probability and area of W and C, shorten the diffusion distance and the reaction time.