FUNDAMENTAL EFFECTS OF COLD-WORK ON SOME COBALT-CHROMIUM-NICKEL-IRON BASE CREEP-RESISTANT ALLOYS

摘要

The influence of cold-working on the creep properties of an alloy containing 20 percent cobalt, 20 percent chromium, 20 percent nickel, and the balance iron and on the same alloy modified by small additions of tungsten alone or tungsten, molybdenum, and columbium in combination was studied. It was concluded that the effects of cold-working on creep resistance were the same for all the alloys studied. This was from the standpoint of the temperature range over which cold-working could be expected to be beneficial (temperatures up to l600° F) and also the maximum amount of cold-working which could be used to improve creep properties at about 1200° F (between 15 and 40 percent). These conclusions were reached in part by studying the creep properties and also in part by studying internal stress relaxation at the test temperatures which previous work had shown to be the controlling factor in the response of such alloys to cold-working.