Abstract 1. A METHOD FOR DEPOSITING AN OXIDATION EROSION RESISTANT COATING ON A NICKEL BASE DIRECTIONALLY SOLIDIFIED EUTECTIC TYPE ALLOY COMPRISING, IN SEQUENCE, THE STEPS OF: DEPOSITING AN INTERMEDIATE COATING LAYER OF NICKEL, COBALT OR NICKEL-COBALT ALLOY ON SAID SUBSTRATE; DIFFUSION HEAT TREATING THE INTERMEDIATE METAL LAYER EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT CHROMIZING STEP TO DIFFUSE THE INTERMEDIATE METAL INTO THE EUTECTIC ALLOY SUBSTRATE; CHROMIZING THE SURFACE OF THE INTERMEDIATE COATING LAYER; DIFFUSION HEAT TREATING EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT ALUMINIZING STEP TO ESTABLISH A CONCENTRATION GRADIENT ACROS THE INTERMEDIATE LAYER WITH THE INITIAL CHROMIUM CONTENT AT THE INTERMEDIATE METAL-EUTECTIC INTERFACE NOT EXCEEDING THE MAXIMUM SOLUBILITY OF CHROMIUM IN THE EUTECTIC PHASES; ALUMINIZING THE SRUFACE OF THE CHROMIUM MODIFIED INTERMEDIATE METAL LAYER INCLUDING A DIFFUSION HEAT TREATMENT AT A TEMPERATURE AND FOR A TIME SUFFICIENT O EFFECT AN ALLOYING REACTION TO FORM ON A OUTER PORTION OF SAID INTERMEDIATE LAYER AN OUTER LAYER OF NIAL OR COAL SUBSTANTIALLY SATURATED WITH CHROMIUM AND HAVING ANY EXCESS CHROMIUM PRECIPITATED THEREIN.
A METHOD FOR DEPOSITING AN OXIDATION EROSION RESISTANT COATING ON A NICKEL BASE DIRECTIONALLY SOLIDIFIED EUTECTIC TYPE ALLOY COMPRISING, IN SEQUENCE, THE STEPS OF: DEPOSITING AN INTERMEDIATE COATING LAYER OF NICKEL, COBALT OR NICKEL-COBALT ALLOY ON SAID SUBSTRATE; DIFFUSION HEAT TREATING THE INTERMEDIATE METAL LAYER EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT CHROMIZING STEP TO DIFFUSE THE INTERMEDIATE METAL INTO THE EUTECTIC ALLOY SUBSTRATE; CHROMIZING THE SURFACE OF THE INTERMEDIATE COATING LAYER; DIFFUSION HEAT TREATING EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT ALUMINIZING STEP TO ESTABLISH A CONCENTRATION GRADIENT ACROS THE INTERMEDIATE LAYER WITH THE INITIAL CHROMIUM CONTENT AT THE INTERMEDIATE METAL-EUTECTIC INTERFACE NOT EXCEEDING THE MAXIMUM SOLUBILITY OF CHROMIUM IN THE EUTECTIC PHASES; ALUMINIZING THE SRUFACE OF THE CHROMIUM MODIFIED INTERMEDIATE METAL LAYER INCLUDING A DIFFUSION HEAT TREATMENT AT A TEMPERATURE AND FOR A TIME SUFFICIENT O EFFECT AN ALLOYING REACTION TO FORM ON A OUTER PORTION OF SAID INTERMEDIATE LAYER AN OUTER LAYER OF NIAL OR COAL SUBSTANTIALLY SATURATED WITH CHROMIUM AND HAVING ANY EXCESS CHROMIUM PRECIPITATED THEREIN.
Claim 2
Independent Claim
172 words
A METHOD FOR DEPOSITING AN OXIDATION EROSION RESISTANT COATING ON A NICKEL BASE DIRECTIONALLY SOLIDIFIED EUTECTIC TYPE ALLOY COMPRISING, IN SEQUENCE, THE STEPS OF: DEPOSITING AN INTERMEDIATE COATING LAYER OF NICKEL, COBALT OR NICKEL-COBALT ALLOY ON SAID SUBSTRATE; DIFFUSION HEAT TREATING THE INTERMEDIATE METAL LAYER EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT CHROMIZING STEP TO DIFFUSE THE INTERMEDIATE METAL INTO THE EUTECTIC ALLOY SUBSTRATE; CHROMIZING THE SURFACE OF THE INTERMEDIATE COATING LAYER; DIFFUSION HEAT TREATING EITHER SEPARATELY OR AS PART OF THE SUBSEQUENT ALUMINIZING STEP TO ESTABLISH A CONCENTRATION GRADIENT ACROS THE INTERMEDIATE LAYER WITH THE INITIAL CHROMIUM CONTENT AT THE INTERMEDIATE METAL-EUTECTIC INTERFACE NOT EXCEEDING THE MAXIMUM SOLUBILITY OF CHROMIUM IN THE EUTECTIC PHASES; ALUMINIZING THE SRUFACE OF THE CHROMIUM MODIFIED INTERMEDIATE METAL LAYER INCLUDING A DIFFUSION HEAT TREATMENT AT A TEMPERATURE AND FOR A TIME SUFFICIENT O EFFECT AN ALLOYING REACTION TO FORM ON A OUTER PORTION OF SAID INTERMEDIATE LAYER AN OUTER LAYER OF NIAL OR COAL SUBSTANTIALLY SATURATED WITH CHROMIUM AND HAVING ANY EXCESS CHROMIUM PRECIPITATED THEREIN.