Alloy articles for use at high temperatures

Claim 1

A HEAT RESISTANT ALLOY ARTICLE WHICH IN NORMAL USE IS EXPOSED TO ELEVATED TEMPERATURES UPWARDS OF 1200*F. AND HAS GREAT STRENGTH AND STABILITY WHEN SUBJECTED TO HIGH STRESSES AT SUCH ELEVATED TEMPERATURES, SAID ARTICLE BEING COMPOSED OF A MACHINABLE, CASTABLE, WELDABLE, HOTWORKABLE ALLOY CONSISTING OF 15% TO 25% CHROMIUM; MORE THAN 25% BUT NOT MORE THAN 45% NICKEL; 10% TO 25% COBALT; MORE THAN 10% BUT NOT MORE THAN 15% TUNGSTEN; UP TO ABOUT 3.5% MOLYBDENUM; AN AGGREGATE OF 0.5% TO 3% OF ONE OR MORE OF THE ELEMENTS OF THE GROUP CONSISTING OF COLUMBIUM, TANTALUM, TITANIUM AND VANADIUM, THE AMOUNT OF ANY SINGLE ELEMENT OF THE LASTNAMED GROUP BEING LESS THAN 2% OF THE ALLOY EXCEPT THE TITANIUM CONTENT BEING NOT IN EXCESS OF 1.5%; UP TO 2% MANGANESE; UP TO 1% SILICON; UP TO 1% CARBON; 0.05% TO 0.25% NITROGEN; AND THE REMAINDER IRON AND INCIDENTAL IMPURITIES, THE IRON CONTENT BEING AT LEAST 5%.