Synthesis and characterization of chromium carbide nanopowders processed by mechanical alloying assisted microwave heating route

Microwave-Assisted Molten-Salt Facile Synthesis of Chromium Carbide (Cr3C2) Coatings on the Diamond Particles

“…Based on the above mentioned XRD, EDS, and SEM analyses, the result indicates that the surface of diamond particles could be successfully coated with Cr using microwave-assisted molten-salt synthesis method, and Cr 2 C 3 was generated during coating simultaneously. The present result is almost similar to the result of the copper-diamond composites with chromium carbide coatings on the diamond particles by vacuum pressure infiltration technique, the coatings on the diamond particles were Cr 7 C 3 , which were formed with a reaction medium of chromium in mixed molten salt of NaCl and KCl (1:1) [6], and were in good agreement with the result of Cr 2 C 3 prepared from nanometer Cr 2 O 3 and nanometer carbon black by microwave heating technique, in which chromium carbide nanopowders were prepared by a microwave heating method at 1000°C for 1 h [43,44].…”

“…For the present study discussed above, Cr powders can absorb the microwaves, accelerating the motion and distribution of Cr metal and resulting in the coatings more uniform and compact [40]. Furthermore, it has been demonstrated that Cr 3 C 2 can also couple effectively with microwaves [43,44], which results in a more uniform temperature gradient within the billet, making the carbide layer formed on the diamond surface more uniform and compact. Figure 7 illustrates the SEM images of Cr-coated diamond by (a) microwave heating and (b) conventional heating at the temperature of 850°C for 1 h. It can be found in Figure 7(a) that the diamond plating by microwave heating is more uniform and homogeneous than that of conventional heating (Figure 7(b)), illustrating that the chromium carbide coating can be synthesized at 850°C for 1 h by the microwave-assisted molten-salt synthesis.…”

“…The results showed that the single phase Cr 7 C 3 powders with a mean diameter of < 200nm were prepared after electrolysis at 2.8 V for 5 h in 850°C CaCl 2 melt. For chromium carbide fabricated by microwave processing, Zhao et al [43] and Zhao and Hu [44] reported the synthesis of chromium carbide nanopowders from nanometer Cr 2 O 3 and nanometer carbon black by microwave heating technique, and using micron-sized chromic oxide (Cr 2 O 3 ) and nanosized carbon black as raw materials via mechanical alloying assisted microwave heating route, concluding that the synthesis temperature and time required by the microwave heating method is at least 400°C lower and 3 h shorter than those required by the conventional approaches for preparing chromium carbide, making the distribution of particle size more uniform, Gunnewiek and Kiminami [45] reported the fast synthesis of porous chromium carbide by microwave-assisted carbothermal reduction from Cr 2 O 3 and carbon black in only 20 min of reaction time, further proved the advantages of microwave heating for the preparation of chromium carbide coatings.…”

Effect of nano-grain carbide formation on electrochemical behavior of 316L stainless steel

“…The high oxygen content also resulted in oxidation of Cr 2 O 3 to form CrO 3 . The formation of carbides in steel treated for 20 min resulted from the reactions between C and compounds in steels 15 , 35 , 41 : …”

Low-Temperature Synthesis of Monolithic Titanium Carbide/Carbon Composite Aerogel

“…[ 1 , 2 , 3 , 4 , 5 ]. Traditional synthesis methods of carbide include the direct carbonization method [ 6 , 7 , 8 ], the carbothermic method [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ], self-propagation high-temperature synthesis [ 16 , 17 , 18 , 19 , 20 ], the mechanical alloying method [ 21 , 22 , 23 , 24 ], the microwave method [ 25 , 26 ], the molten salt method [ 27 , 28 , 29 , 30 ] and the plasma method [ 31 , 32 ]. The carbothermic method is widely promoted because it possesses the advantages of low cost, simple equipment, high production efficiency and mass production capacity.…”