Određivanje otpornosti na dejstvo kavitacije uzoraka pirofilita

Abstract

U radu je ispitivana otpornost pod dejstvom kavitacije uzoraka sinterovanog pirofilita. Polazni uzorak pirofilita iz ležišta Parsović-BiH mleven je u vibracionom mlinu na granulaciju 20mm, presovan je i sinterovan na temperaturama (ºC): 1000; 1100; 1200. Za procenu kavitacione otpornosti praćena je promena mase uzorka u funkciji vremena delovanja kavitacije. Primenjena je ultrazvučna vibraciona metoda sa stacionarnim uzorkom prema standardu ASTM G32. Izračunate su kavitacione brzine za sve uzorke, kao osnovni pokazatelj otpornosti materijala pod dejstvom kavitacije. Promena morfologije površine uzorka sa vremenom ispitivanja praćena je primenom skenirajuće elektronske mikroskopije. Na osnovu vrednosti kavitacione brzine i analize morfologije oštećenja površine određena je kavitaciona otpornost ispitivanih uzoraka na bazi pirofilita. Dobijeni rezultati ukazuju da uzorci sinterovanog pirofilita imaju zadovoljavajuću otpornost na dejstvo kavitacije i mogu se primeniti u uslovima manjih kavitacionih opterećenja.

The resistance under the action of cavitation of sintered pyrophillite samples was investigated. The initial sample of pyrophillite from the Parsovic-BiH deposit was ground a vibrating mill to a granulation of 20 mm, pressed and sintered at temperatures (⁰C): 100; 1100; 1200. To assess cavitation resistance, the change in sample mass as a function of cavitation time was monitored. The cavitation erosion test was performed using the ultrasonic vibratory cavitation test method according to the ASTM G-32 standard. Cavitation velocites were calculated for all samples, as a basic indicator of the resistance of the material under the action of cavitation. The change in the morphology of the surface with the test time was followed by scanning electron microscopy. Based on the values of cavitation velocity and analysis of the surface damage morphology, the cavitation resistance of the tested samples based on pyrophillite was determined. The obtained results indicate that the samples of sintered pyrophillite have satisfactory resistance to the action of cavitation and be applied in conditions of lower cavitation loads.