Özet:

Copper (Cu) based composites, especially compositions containing refractory metals such as tungsten (W) or molybdenum, exhibit superior physical and mechanical properties over a wide range of temperatures compared to conventional materials. Due to their high hardness, good electrical and thermal conductivities, and excellent arc-erosion resistance; Cu-based refractory metal reinforced composites are frequently used as electrical contact materials. Although, it is possible to produce aforementioned composites via ball milling technique, this method also contains several parameters that have to be investigated in detail, such as process control agent, milling speed, ball-to-powder weight ratio, milling time, and so on. In this paper; the effect of process control agent, which is one of the most important parameters in ball milling technique, on production of Cu-based W-reinforced composite powder was investigated. For this purpose, two different liquid process control agents, namely ethanol and methanol were separately added to powder mixtures containing elemental Cu and W, and then ball milling experiments were performed using a two stationary planetary-type ball mill. The effects of ethanol and methanol additions on particle size and morphology of Cu25W powder mixture was investigated using laser diffraction analysis (Mastersizer) and scanning electron microscopy (SEM). It was found that average particle size values of both compositions decreased with increasing milling duration. Considering its improved particle size reduction effectiveness as a process control agent, methanol at the amount of 2 wt.% was found to be more effective comparing to the same amount of ethanol in terms of producing Cu25W composite powder. Besides, more homogeneous dispersion of elements was achieved in powder mixture containing methanol after ball milling duration of 25 hours.

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