Gas-loading furnace for deuterium-charged alloy-casting.

A furnace was developed and characterized to allow for safe and controlled gas-loading or degassing of alloys. This oven is able to process samples under varying atmospheres, such as high vacuum or nitrogen containing 10 vol. % deuterium, as well as for pressures up to 800 hPa. Thermal desorption spectroscopy and scanning electron microscopy demonstrate the enhancing effects of high loading-gas concentration, high pressures, high temperatures above liquidus (50-150 K above the liquidus temperature of the cast hypoeutectic aluminum-copper model-alloy), and long holding times (up to 60 min) on the amount of retained gas in the solidified sample. Lack of copper segregation in the casting is confirmed by energy dispersive x-ray diffraction and Rutherford backscattering spectroscopy. It is shown that the facility allows for the controlled generation of distinct amounts of gas pores, down to a nil amount (only shrinkage porosity appearing in the sample).