摘要 |
<p>A nickel- or cobalt-based alloy of the type containing, by weight, 5 to 40% chromium, up to about 10% aluminum, up to about 10% titanium, up to about 30%, in combination, of elements from the group tantalum, tungsten, molybdenum, columbium, rhenium, or vanadium, up to about 2% silicon, up to about 5% hafnium, and up to about 5% reactive elements such as lanthanum, yttrium or other rare earths. Manganese is present in an amount from 0.1 to 12%, preferably 0.5 to 4%. Silicon in amounts from 1.0 to 2.0 by weight, or hafnium in amounts from 0.1 to 5.0% by weight may also be used. Alloys in accordance with this invention are particularly suitable for casting by the single crystal technique; however, the alloys can also be used in the production of polycrystalline components such as directionally solidified, conventionally solidified (equiaxed), wrought, or dispersion strengthened materials. In the latter case, grain boundary modifiers such as carbon, boron, zirconium and hafnium are utilized. The alloys produced are advantageously used as structural alloys for use in gas turbine rotor blades and stator vanes which require high temperature strength, high temperature ductility, oxidation and hot corrosion resistance, and microstructural stability.</p> |