Abstract: In continuous casting of a non-ferrous metal melt by a gas-pressure impartation method, the cast skin of a large size ingot is usually impaired by the chilling effect of a mold, and it is difficult to stably produce a large size ingot. This difficulty is overcome by controlling the quantity of gas inflow in accordance with the quantity of the light emitted from a light source provided below a mold and laterally to an ingot, which light reaches a separate chamber for gas-pressure impartation.

Abstract: A direct chill casting of metals, particularly hot top casting of aluminum and its alloy, is improved by applying a gas pressure to the metals from directly below the overhang of a feed reservoir for receiving a melt to be cast.The direct chill casting is further improved by supplying a lubricating oil from a slit for conveying the gas to the inner wall of the mold.By using the process and the apparatus according to the invention, ingots having excellent smooth surfaces and reduced segregation can be reliably produced with a reduction in the amount of the lubricating oil used.

Abstract: An aluminum alloy consisting essentially of 8 to 15% by weight of silicon, 0.05 to 0.7% by weight of magnesium, 1 to 4.5% by weight of copper, the balance being aluminum, wherein a silicon crystal in eutectic structure crystallized out in an aluminum matrix has a mean grain size not larger than 5 microns and intermetallic compounds of magnesium and copper are finely precipitated in the matrix as age-hardening elements for the matrix, and the alloy has at least 40 kg/mm.sup.2 tensile strength and at least 10% elongation, good antiwearing and excellent workability.The disclosure is also concerned with a method of making the above-mentioned aluminum alloy.