Abstract:
The ball milling time affects the magnetic properties its product. Research on the
magnetic properties and the product composition of natural sand of the Rokan River as
a function of optimum time in ball milling has been done . The natural sand samples of
Rokan River that has collected with a mass of 10 Kg were dried under the sun ray
before the separation process between magnetic and non-magnetic particles using an
Iron Sand Separator (ISS). The result of the separation with the Iron Sand Separator is
called product of ISS. The product of ISS was milled as a function of time of 60 hours,
70 hours, 80 hours, 90 hours, 95 hours, 100 hours, 105 hours and 110 hours with 16
pieces of iron balls that has 1.5 cm in diameter. The product of the ball milling then
separated using Neodymium Iron Boron (NdFeB), the result of this separation is called
ball milling product (BM product). The results of this research indicate that the
magnetic induction values of natural samples of Rokan river, ISS product and BM
product in the ranged from 12,338-14,850 mT for the same current of 1000 mA, while
the magnetic susceptibility values obtained in the range 3393,950-24444.817 × 10-5.
The identification of element content in natural sand was done using X-Ray
Fluorescence (XRF) for ball milling product (BM product) as a function of time of 95
hours, 100 hours, 105 hours, and 110 hours. The results of XRF identification showed
that the composition of Fe increased from 30.043% to 51.201%, while the composition
of Si decreased from 36.715% to 21.215%. The results of research showed that the
optimum time for the ball milling method was 100 hours.
