TN942 : Increasing the wear resistant of the grinding media and liners of the grinding equipment by producing an wear resistant nano coating in order to increase performance
Thesis > Central Library of Shahrood University > Mining, Petroleum & Geophysics Engineering > PhD > 2019
Authors:
Abstarct: Nanotechnology developments and its vast application is entirely known by everyone. The effect of high entropy alloy nano coating to increase the abrasive resistance against grinding load on the mining grinding load equipment substrate was investigated in the study. To do so, oxyfuel powder spray (OFP) was chosen as the most accessible method after examining the most proper and economical methods of coating on target equipment. Since most costs are incurred in abrasion and crushing sectors, milling rod and ball were selected for coating in order to enhance abrasive resistance. Therefore, a high entropy nano alloy was produced. The results of atomic microscope of Fe-SEM and EDX images analysis showed that the particles size was less than 20 nanometer and they are uniformly scattered. Nano coating tests require high precision, so, to compare the nano sizes of the high entropy alloy before and after welding, SEM atomic microscope analysis was applied at each phase. After studying the results of hardness measurement baxsed on ASTMG-65 is was realized that 67 Rockwell was gained for the hardness of the high entropy alloy. The assumed hardness and the nanostructure of the high entropy alloy have modern insight into creating high resistance against abrasion to milling rod, ball, and substrate. With the purpose of investigating the usage of the invented high entropy nano alloy in treating minerals, three mineral samples were chosen as reagent sample for mill abrasion test. The results of bond abrasion index and use of a standard baxse alloy compared to the coated part by high entropy nano alloy indicated that the rates of abrasion for iron ore, oxide copper, and porphyry copper samples were reduced from 0.1647 gr to 0.0908 gr, 0.1472 gr to 0.0803 gr, and 0.1472 gr to 0.0837 gr respectively. The results of standard deviation, repeatability and duplicability in bond abrasion test for the steel blade coated by high entropy nano alloy 0.00016, 0.00047, and 0.00040 were calculated sequentially for the iron ore sample, and 0.0003, 0.000047, and 0.00042 for the oxide copper ore sample. The results of corrosion test on rod mill and ball was evaluated, compared according to baxse electrode SCE, observed and reported once before the coating and the second time after coating by high entropy nano alloy. The results showed that the corrosion potential reaches more positive amount from - 400 mV exposed to SCE baxse electrode to + 1000 mV, the corrosion rate in the ordinary ball reduced from 0.211 millimeter per year to 0.0006 millimeter per year.
Keywords:
#Nano High Entropy Alloy (NN-HEA) #Hard coatings #Abrasion resistant of mining grinding load equipment #MD simulations #corrosion resistant #Optimizing energy consumption mining grinding load Link
Keeping place: Central Library of Shahrood University
Visitor:
Keeping place: Central Library of Shahrood University
Visitor: