Abstract: A gas amount measuring device including a vacuum container, a first pipe, an air release valve being attached to the first pipe, a second pipe, a calibration gas generator being attached to the first pipe, a third pipe, a vacuum gauge, a first valve, a leak valve, a second valve, a turbomolecular pump, a third valve, and a roughing pump being attached to the third pipe in order from a vacuum container side, a first bypass pipe connecting the third pipe between the vacuum container and the first valve to the third pipe between the leak valve and the second valve, a fourth valve being attached to the first bypass pipe, and a second bypass pipe connecting the third pipe between the leak valve and the second valve to the third pipe between the third valve and the roughing pump, a fifth valve being attached to the second bypass pipe.

Abstract: Disclosed is a method of adding silicon to aluminum. The method is characterized in that silicon particles having a diameter ranging between 2 mm and 50 mm are added to a molten aluminum together with a flux represented by the general formula XaMFb, where "X" represents an element included in the third or fourth period of the Periodic Table, "M" is a III or IV group element of the Periodic Table, and "F" is fluorine. A part of the flux may be added in the form of coating on the surface of the silicon particle.