Method of making oxidation-resistant alloy melt and alloy casting from such a melt, oxidation-resistant alloy melt and alloy casting

摘要

In the present invention, there is disclosed a magnesium-based casting alloy having good salt-spray corrosion resistance and improved creep resistance, tensile yield strength and bolt-load retention, particularly at elevated temperatures of at least 150 degC. The inventive alloy comprises, 2 to 9 percent by weight of aluminum and 0.1 to 7 percent by weight of strontium, with the balance being magnesium except for impurities commonly found in magnesium alloys. A method of making an oxidation-resistant alloy melt, and the alloy melt prepared by such a method, are also provided. The inventive method comprises: melting the alloying metals under an atmosphere of an inert gas selected from a mixture of carbon dioxide and sulfur fluoride gas, a mixture of nitrogen and sulfur dioxide gas, and combinations thereof. Further provided is a method of making a magnesium-based alloy casting from the above-identified alloy melt, and the alloy casting prepared by such a method.