Accession Number : ADA263747


Title :   Oxidation and Hot Corrosion of Superalloys Rene 100 and X-40 at Temperatures of 1475 F to 2000 F


Descriptive Note : Final rept.,


Corporate Author : ARMY RESEARCH LAB WATERTOWN MA MATERIALS DIRECTORATE


Personal Author(s) : Levy, M ; Falco, J J ; Pettit, F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a263747.pdf


Report Date : Feb 1993


Pagination or Media Count : 25


Abstract : The oxidation resistance and hot corrosion resistance of two superalloys, Rene 100 and X-40, and an aluminide coating for the protection of one of the superalloys are compared. The comparison is made by using tube- furnace oxidation and hot corrosion tests employing a Mettler TGA apparatus at temperatures of 1475 deg F to 2200 deg F. For hot corrosion tests the samples were precoated with Na2SO4 prior to heating to the desired temperature and introducing air at a flow rate of 57 cm/min. The oxidation behavior to Rene 100 was poor compared to that-of the X-40 alloy, especially at temperatures above 1900 deg F. The X-40 alloy was found to be more resistant to the initiation of hot corrosion than Rene 100. Both alloys, however, undergo attack at rates consistent with an alloy-induced fluxing mechanism. An aluminide coating on Rene 100 caused the initiation of hot corrosion to be delayed. Attack did occur when cumulative applications of Na2SO4 were used. The coatings were penetrated by the Na2SO4 in localized areas after exposure times of less than 200 hours. The hot corrosion test has validity for mechanisms whereby the degradation process is sustained by reaction products from the alloy. It, therefore, can be used to compare the time to establish such conditions in alloys. Rene 100 is more susceptible to this condition than X-40.... Superalloys, Nickel-base superalloys, Cobalt-base superalloys Oxidation resistance, Corrosion, Sulfidation, Aluminide Coatings.


Descriptors :   *CORROSION RESISTANCE , *COATINGS , *OXIDATION , *SUPERALLOYS , FLUX(RATE) , COMPARISON , RATES , FLOW RATE , HEATING , PROTECTION , NICKEL , OXIDATION RESISTANCE , FURNACES , COBALT , TUBES , ALUMINIDES , AIR , DEGRADATION , SODIUM SULFATES , TEST AND EVALUATION , TEMPERATURE


Subject Categories : Physical Chemistry
      Coatings, Colorants and Finishes
      Properties of Metals and Alloys
      Thermodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE