Wide-gap filler material

Abstract

This invention relates to a composition for repairing metallic articles which in its initial state is in the form of an adhesive, self-supporting putty, capable of being molded including 5-15% by weight of a sacrificial binder containing at least one acrylic resin and volatile solvent. The invention also relates to a kit for the composition and methods for repair.

1 - 37 . (canceled)  
   
   
       38 . A method of repairing a metallic alloy article having a defect cavity greater than about 0.010 inches (2.54×10 −4  m) in maximum width, the method comprising the steps of: 
 providing a first metallic filler material in the defect cavity such that the metallic filler material substantially fills the cavity, the composition of the first metallic filler material corresponding substantially to that of the metallic alloy article;    providing a second metallic filler material over the first metallic filler material, wherein the second metallic filler material includes between about 0 wt. % and about 40 wt. % metallic filler material of a composition corresponding substantially to the metallic alloy article, and between about 100 wt. % and about 60 wt. % metallic filler material having the same basis as the composition of the metallic alloy article and including a melting point depressant in an amount substantially in excess of that in the metallic alloy article;    effecting isothermal solidification by thermally processing the article through a heat treatment comprising:    heating the article to a temperature above the solidus of the second metallic filler material to melt the second metallic filler material and isothermally solidify repair of the defect cavity greater than about 0.010 inches (2.54×10 −4  m) in maximum width.    
   
   
       39 . The method of  claim 38  wherein the metallic alloy article is a nickel base superalloy article.  
   
   
       40 . The method of  claim 38  wherein the defect cavity has a maximum width between about 0.010 inches (2.5×10 −4  m) and about 0.030 inches (7.6×10 −4  m).  
   
   
       41 . The method of  claim 38  wherein surface oxides are removed from the defect cavity prior to providing the first metallic filler material in the defect cavity.  
   
   
       42 . The method of  claim 38  wherein the metallic alloy article comprises a composition in weight percent of 9% chromium, 10% cobalt, 12.5% tungsten, 1% columbium, 2% titanium, 5% aluminum, 2% hafnium, 0.015% boron, balance nickel.  
   
   
       43 . The method of  claim 38  wherein between about 1% and 3%, boron, by weight, is present as the melting point depressant in the second metallic filler material.  
   
   
       44 . The method of  claim 38  wherein the article is heated to between about 2000° F. (1093° C.) and about 2400° F. (1316° C.) for between about 5 hours and about 30 hours, whereby the second metallic filler material melts and infiltrates the first metallic filler material to produce a void free structure.  
   
   
       45 . A method of repairing a metallic alloy article having a defect cavity, the method comprising the steps of: 
 providing a first metallic filler material in the defect cavity such that the metallic filler material substantially fills the cavity, the composition of the first metallic filler material corresponding substantially to that of the metallic alloy article;    providing a second metallic filler material over the first metallic filler material, wherein the second metallic filler material includes between about 0 wt. % and about 40 wt. % metallic filler material of a composition corresponding substantially to the metallic alloy article, and between about 100 wt. % and about 60 wt. % metallic filler material having the same basis as the composition of the metallic article and including a melting point depressant in an amount substantially in excess of that in the metallic alloy article;    effecting isothermal solidification by thermally processing the article through a heat treatment comprising: 
 heating the article to a temperature (T1) capable of sintering the first metallic filler material, but below the solidus of the second metallic filler material, such as between about 2000° F. (1093° C.) and about 2400° F. (1316° C.) for about 4 hours; and then  
 holding at a temperature (T2) above the solidus of the second metallic filler material, such as between about 2000° F. (1093° C.) and about 2400° F. (131 6° C.) for between about 5 hours and about 30 hours to melt the second metallic filler material and isothermally solidify the repair, whereby T2 is greater than T1.  
   
   
   
       46 . A method of repairing a metallic alloy article having a defect cavity greater than about 0.010 inches (2.5×10 −4  m) in maximum width, the method comprising the steps of: 
 providing a first metallic filler paste in the defect cavity such that the metallic filler paste substantially fills the cavity, the metallic filler paste comprising a binder and a first metallic filler material having composition corresponding substantially to that of the metallic alloy article;    providing a second metallic filler paste over the first metallic filler paste, wherein the second metallic filler paste comprises a binder and a second metallic filler material having between about 0 wt. % and about 40 wt. % metallic filler material of a composition corresponding substantially to the metallic article, and between about 100 wt. % and about 60 wt. % metallic filler material having the same basis as the composition of the metallic alloy article and including a melting point depressant in an amount substantially in excess of that in the metallic alloy article;    effecting isothermal solidification by thermally processing the article through a heat treatment by: 
 heating the article to a temperature between about 1000° F. (538° C.) and about 1200° F. (649° C.) and holding at that temperature until the binder is driven off;  
 holding at a temperature capable of sintering the first metallic filler material of the first metallic filler paste, but below solidus of the second metallic filler paste, between about 1850° F. (1010° C.) and about 2200° F. (1204° C.) for about 4 hours; and  
 holding at a third temperature, between about 2000° F. (1093° C.) and about 2400 ° F. (1316° C.) for between about 5 hours and about 30 hours, to melt the second metallic filler paste and thereby isothermally solidify a repair of the defect cavity greater than about 0.010 inches (2.5×10 −4  m) in maximum width.  
   
   
   
       47 . A method of repairing a metallic alloy article having a defect cavity, the method comprising the steps of: 
 providing a first metallic filler material in the defect cavity such that the metallic filler material substantially fills the cavity, wherein the first metallic filler material is a blend of at least two distinct metallic filler materials, one metallic filler material, present in at least 60 wt. %, corresponds substantially in composition to that of the metallic alloy article, and another metallic filler material has the same basis as the metallic alloy article and includes a melting point depressant in an amount substantially in excess of that in the article;    providing a second metallic filler material over the first metallic filler material, wherein the second metallic filler material includes between about 0 wt. % and about 40 wt. % metallic filler material of a composition corresponding substantially to the metallic alloy article, and between about 100 wt. % and about 60 wt. % metallic filler material having the same basis as the metallic alloy article and including a melting point depressant in an amount substantially in excess of that in the metallic alloy article;    effecting isothermal solidification by thermally processing the article through a heat treatment comprising: 
 heating the article to a temperature above the solidus of the second metallic filler material to melt the second metallic filler material and isothermally solidify the repair.  
   
   
   
       48 . A method of repairing a metallic alloy article having a defect cavity of from 0.030 inch to ⅛ inch in width, the method comprising the steps of: 
 providing a first metallic filler material in the defect cavity such that the first metallic filler material substantially fills the cavity, the first metallic filler material comprising a first metallic filler and a first binder, the composition of the first metallic filler corresponding substantially to the composition of the metallic alloy article, the first binder consisting essentially of 25-50% by weight of a first thermoplastic resin, 25-60% by weight of a first solvent for the first thermoplastic resin which substantially vaporizes at temperatures up to 200° C., 0-30% by weight of a first plasticizer and 0-5% by weight of a first wetting agent; the first metallic filler material comprising 85-95% by weight of the first metallic filler and 5-15% by weight of the first binder;    providing a second metallic filler material over the first metallic filler material, wherein the second metallic filler material includes a second metallic filler and a second binder, the second metallic filler comprising about 100 wt. % of a metallic filler having the same basis as the composition of the metallic alloy article and including a melting point depressant in an amount substantially in excess of any amount of melting point depressant in the metallic alloy article, the second binder consisting essentially of 25-50% by weight of a second thermoplastic resin, 25-60% by weight of a second solvent for the second thermoplastic resin which substantially vaporizes at temperatures up to 200° C., 0-30% by weight of a second plasticizer and 0-5% by weight of a second wetting agent; the second metallic filler material comprising 85-95% by weight of the second metallic filler and 5-15% by weight of the second binder;    effecting isothermal solidification by thermally processing the article through a heat treatment comprising:    heating the article to a temperature up to 200° C. to remove the solvents in the first and second binders so as to dry the article;    heating the article to a temperature sufficient to decompose remaining binder into gaseous products; heating the article to a temperature sufficient to evaporate the gaseous products; and    heating the article to a temperature above the solidus of the second metallic filler material to melt the second metallic filler material and isothermally solidify repair of the defect cavity.    
   
   
       49 . The method of  claim 48  wherein the defect cavity has a width of about 0.030 inches (7.6×10 −4  m).  
   
   
       50 . The method of  claim 48  wherein about 2.7% boron by weight is present as the melting point depressant in the second metallic filler material.  
   
   
       51 . The method of  claim 48  wherein the article is heated to between about 1176° C. and about 1204° C. for between about 5½ hours and about 7 hours, whereby the second metallic filler melts and infiltrates the first metallic filler material to produce a void free structure.  
   
   
       52 . A method of repairing a metallic alloy article having a defect cavity of from about 0.010 inches to about ⅛ inch in width, the method comprising the steps of: 
 providing a first metallic filler material in the defect cavity such that the first metallic filler material substantially fills the cavity, the first metallic filler material comprising a first binder and a first metallic filler, the first metallic filler having a composition corresponding substantially to the composition of the metallic alloy article; the first binder consisting essentially of 25-50% by weight of a first thermoplastic resin, 25-60% by weight of a first solvent for the first thermoplastic resin which substantially vaporizes at temperatures up to 200° C., 0-30% by weight of a first plasticizer and 0-5% by weight of a first wetting agent; the first metallic filler material comprising 85-95% by weight of the first metallic filler and 5-15% by weight of the first binder;    providing a second metallic filler material over the first metallic filler material, wherein the second metallic filler material comprises a second binder and a second metallic filler, the second metallic filler comprising about 100 wt. % of a metallic filler having the same basis as the composition of the metallic alloy article and including a melting point depressant in an amount substantially in excess of any amount of melting point depressant in the metallic alloy article, the second binder consisting essentially of 25-50% by weight of a second thermoplastic resin, 25-60% by weight of a second solvent for the second thermoplastic resin which substantially vaporizes at temperatures up to 200° C., 0-30% by weight of a second plasticizer and 0-5% by weight of a second wetting agent; the second metallic filler material comprising 85-95% by weight of the second metallic filler and 5-15% by weight of the second binder; effecting isothermal solidification by thermally processing the article through a heat treatment comprising:    heating the article to a temperature up to 200° C. to remove the solvents in the first and second binders so as to dry the article;    heating the article to a temperature sufficient to decompose remaining binder into gaseous products;    heating the article to a temperature sufficient to evaporate the gaseous products; and    holding at a temperature capable of sintering the first metallic filler of the first metallic filler material, but below the solidus of the second metallic filler material; and holding at a third temperature sufficient to melt the second metallic filler material and thereby isothermally solidify the repair of the defect cavity.