Oven rack having an integral lubricious, dry porcelain surface

Abstract

A lubricious porcelain coated steel wire oven rack. The preferred coated steel wire oven rack includes a plurality of elongated steel wire members joined together to form an oven rack having an outer surface. The plurality of elongated steel wire members are made from a cold drawn steel rod material containing from about 80 to about 99.9% by weight of iron, up to about 0.08% by weight of carbon and from about 0.001 to about 0.2% by weight of a carbon stabilizing transition metal, preferably selected from the group consisting of Vanadium, Tantalum, Titanium and Niobium. In a preferred embodiment, the porcelain surface of the oven rack includes a dry lubricant selected from carbon; graphite; boron nitride; cubic boron nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide; tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.

1 . A lubricious glass-coated metal cooking article capable of withstanding repeated heating and cooling between room temperature and at least 500° F. without chipping or cracking the glass coating, 
 wherein the glass coating includes about 0.1 to about 20% by weight of a homogeneously distributed dry refractory lubricant material selected from the group consisting of carbon; graphite; boron nitride; cubic boron nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide, tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.    
   
   
       2 . The lubricious glass-coated, metal article of  claim 1 , wherein the metal is drawn steel rod and the amount of carbon and the degree of diameter reduction of the steel rod are selected to provide sufficient cavities in the drawn steel such that the glass coating does not chip or crack when the glass-coated article is heated to a temperature above 900° F.  
   
   
       3 . The lubricious glass-coated, drawn steel rod article of  claim 2 , wherein the glass coating is a porcelain material applied in a thickness is the range of 1 to 20 mils.  
   
   
       4 . The lubricious glass-coated, drawn steel rod article of  claim 3 , wherein the glass coating is a porcelain material applied in a thickness is the range of 4 to 10 mils.  
   
   
       5 . The lubricious glass-coated, metal article of  claim 1 , wherein the article is a cooking surface selected from an oven rack, oven ladder rack, burner grate, and a barbeque grill rack.  
   
   
       6 . The lubricious glass-coated, drawn steel article of  claim 3 , wherein the glass coating is a porcelain enamel material.  
   
   
       7 . The lubricious glass-coated, drawn steel article of  claim 6 , wherein the porcelain is applied in multiple coating steps.  
   
   
       8 . The lubricious glass-coated, metal article of  claim 1 , wherein the metal is a metal rod drawn to reduce the diameter at least about 20%.  
   
   
       9 . The lubricious glass-coated, metal article of  claim 8 , wherein the metal is a metal rod drawn to reduce the diameter at least about 30%.  
   
   
       10 . The lubricious glass-coated, metal article of  claim 9 , wherein the metal rod is drawn to reduce the diameter at least about 40%.  
   
   
       11 . The lubricious glass-coated, metal article of  claim 10 , wherein the metal rod is drawn to reduce the diameter at least about 45%.  
   
   
       12 . The lubricious glass-coated, metal article of  claim 11 , wherein the metal rod is drawn to reduce the diameter at least about 50%.  
   
   
       13 . The lubricious glass-coated, metal article of  claim 1 , wherein the metal is a steel rod drawn through cold dies to gradually reduce the rod diameter.  
   
   
       14 . The lubricious glass-coated, metal article of  claim 1 , wherein the metal is steel rod drawn in a cold die to provide sufficient cavities in the metal for receiving hydrogen emitted from the metal such that the glass coating is not damaged by the emitted hydrogen when the article is heated to a temperature above 900° F.  
   
   
       15 . A lubricious glass-coated steel article, said article capable of withstanding a hydrogen-emitting temperature sufficient to emit hydrogen gas from the steel such that hydrogen gas emitted from the steel is contained within cavities formed in the steel during drawing, without escaping through the glass coating, such that the glass coating does not chip or crack at said hydrogen-emitting temperature, wherein the steel rod is drawn to reduce the diameter of the steel rod at least 20%, and the steel comprises the following components by weight:  
     
       
         
               
               
             
                   
               
                   
               
                 Iron 
                 about 80% to about 99.9%; 
               
                 Carbon 
                 up to about 0.08%; and 
               
                 A transition metal selected from Vn, Ta, 
                 0.001% to about 0.2%, 
               
                 Ti, Ni or mixture of any two or more 
               
                   
               
                   
               
           
              
              
             
             
              
              
              
              
              
              
             
          
         
       
       wherein the amount of carbon in the steel rod material, the amount of carbon stabilizing transition metal in the steel rod material and the degree to which the diameter of the cross-sectional area of the steel rod material is reduced, when the steel wire is drawn from the steel rod material, are selected to prevent chipping of the glass material away from the outer surface of the article due to the release of hydrogen gas from the steel wire members when the glass-coated steel wire members are heated to a temperature above 900° F.; and  
       wherein the glass surface includes a dry refractory lubricant material or has been processed for increased lubricity to achieve a reduction in a coefficient of friction in porcelain-to-porcelain sliding contact.  
     
   
   
       16 . The lubricious glass coated, drawn steel rod article of  claim 15 , wherein the amounts of iron, carbon, and transition metal and the degree of diameter reduction of the steel rod are selected to provide sufficient cavities in the drawn steel such-that the glass coating does not chip or crack when the glass-coated article is heated to a temperature above 900° F.  
   
   
       17 . The lubricious glass-coated, drawn steel rod article of  claim 16 , wherein the glass coating is a porcelain material applied in a thickness is the range of 1 to 20 mils.  
   
   
       18 . The lubricious glass-coated, drawn steel rod article of  claim 17 , wherein the glass coating is a porcelain material applied in a thickness is the range of 4 to 10 mils.  
   
   
       19 . The lubricious glass-coated, drawn steel product of  claim 15 , wherein the article is a cooking surface selected from an oven rack, oven ladder rack, and a barbeque grill rack.  
   
   
       20 . The lubricious glass-coated, drawn steel article of  claim 17 , wherein the glass coating is a porcelain enamel material.  
   
   
       21 . The lubricious glass-coated, drawn steel article of  claim 20 , wherein the porcelain enamel material is applied in multiple coating steps.  
   
   
       22 . The lubricious glass-coated, drawn steel article of  claim 15 , wherein the steel rod is drawn to reduce the diameter of the steel rod at least about 30%.  
   
   
       23 . The lubricious glass-coated, drawn steel article of  claim 22 , wherein the steel rod is drawn to reduce the diameter of the steel rod at least about 50%.  
   
   
       24 . The lubricious glass-coated, drawn steel article of  claim 22 , wherein the steel rod is drawn through cold dies to gradually reduce the rod diameter.  
   
   
       25 . The lubricious, glass-coated drawn steel article of claim  1 S, wherein the dry refractory lubricant material is selected from the group consisting of consisting of carbon; graphite; boron nitride; cubic boron-nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide;tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.  
   
   
       26 . A lubricious glass-coated steel wire oven rack comprising: 
 a plurality of elongated steel wire members joined together to form an oven rack having an outer surface;    the plurality of elongated steel wire members being made from a steel rod material containing up to about 0.03% by weight carbon;    the plurality of elongated steel wire members being made from the steel rod material by drawing the steel rod material to form steel wire;    wherein the diameter of the cross-sectional area of the steel rod material is reduced by at least about 20% when the steel rod material is drawn to form the steel wire;    the outer surface of the oven rack being coated by a lubricious glass material;    wherein the amount of carbon in the steel rod material and the degree to which the diameter of the cross-sectional area of the steel rod material is reduced, when the steel wire is drawn from the steel rod material, are selected to prevent chipping of the glass material away from the outer surface of the article due to the release of hydrogen gas from the steel wire members when the glass-coated steel wire members are heated to a temperature above 900° F.    
   
   
       27 . The lubricious glass-coated steel wire oven rack of  claim 26 , wherein the glass material is porcelain coated onto the outer surface of the, steel wire members by first applying a base coat and thereafter applying a lubricious top coat containing 0.1% to about 20% by weight of a homogeneously dispersed dry lubricant material selected from the group consisting of carbon; graphite; boron nitride; cubic boron nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide; tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.  
   
   
       28 . The lubricious glass-coated steel wire oven rack of  claim 26 , wherein the coating thickness is in the range of 4 to 10 mils.  
   
   
       29 . The lubricious glass-coated steel wire oven rack of  claim 26 , wherein the lubricious glass material coating includes two separate applied coatings in which a first ground coat of powdered glass is applied and then a second top coat of lubricious powdered glass is applied in a subsequent coating application.  
   
   
       30 . The lubricious glass-coated steel wire oven rack of  claim 29 , wherein the two applied glass coatings are electrostatically applied.  
   
   
       31 . A method of making a lubricious glass-coated steel wire oven rack, comprising the steps of: 
 a) providing steel rod material containing from about 80 to about 99.9% by weight of iron, up to about 0.08% by weight of carbon and from about 0.001 to about 0.2% by weight of carbon stabilizing transition metal selected from the group consisting of Vanadium, Tantalum, Titanium and Niobium;    b) drawing the steel rod material to form steel wire, wherein the diameter of the cross-sectional area of the steel rod material is reduced by at least about 20%;    c) forming a plurality of elongated steel wire members from said steel wire;    d) joining the plurality of steel wire members to one another to form interconnected parts of a steel wire oven rack; and    e) coating the steel wire oven rack with a lubricious porcelain;    wherein the amount of carbon in the steel rod material, the amount of carbon stabilizing transition metal in the steel rod material and the degree to which the diameter of the cross-sectional area of the steel rod material is reduced, when the steel wire is drawn from the steel rod material, are selected to prevent chipping or spalling of the glass material away from the outer surface of the article due to the release of hydrogen gas from the steel wire members when the glass-coated steel wire members are heated to a temperature above 900° F.    
   
   
       32 . The method of  claim 31 , wherein the lubricious porcelain is coated onto the steel wire oven rack in a wet coating process selected from the group consisting of wet spray, electrostatic wet spray, wet flow coating, wet dip, electro-phoretic deposition, and a combination thereof, followed by heating to a temperature of about 1500° F. to about 1600° F. or higher.  
   
   
       33 . The method of  claim 31 , wherein the lubricious porcelain is coated onto the steel wire oven rack by an immersion or flow coating method selected from the group consisting of hand dipping, tong dipping, automatic dip machine coating, electrophoretic deposition, flow coating, and a combination thereof, followed by heating to a temperature of about 1550° F. or higher.  
   
   
       34 . The method of  claim 32 , wherein the lubricious porcelain coated steel wire oven rack is heated to about 1500° F. to about 1600° F. for about 25 minutes prior to cooling.  
   
   
       35 . The method of  claim 31 , wherein the steel rod is drawn through cold dies to gradually reduce the diameter of the steel rod at least about 20%.  
   
   
       36 . The method of  claim 31 , wherein the coated lubricious porcelain comprises porcelain enamel including a dry lubricant selected from the group consisting of carbon; 
 graphite; boron nitride; cubic boron nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide; tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia;    antimony; antimony oxide; antimony trioxide; and mixtures thereof.    
   
   
       37 . The method of claims  36  wherein the porcelain enamel and dry lubricant portion of the porcelain enamel are milled together.  
   
   
       38 . A lubricious metal carbide-coated steel wire oven rack designed to be received within a porcelain- or ceramic-coated oven cavity, the coated steel wire oven rack comprising: 
 a plurality of elongated steel wire members joined together to form an oven rack shape having an outer surface;    the plurality of elongated steel wire members being made from the steel rod material by drawing the steel rod material to form said steel wire members;    wherein the diameter of the steel rod material is reduced by at least about 20% when the steel rod material is drawn to form the steel wire members;    the outer surface of the oven rack having a lubricious carbon or diamond surface formed by treating the metal carbide with a halogen etchant gas at a temperature in the range of 100° C. to 4000° C.    
   
   
       39 . A method of cleaning a porcelain-coated steel wire oven rack capable of withstanding oven cleaning temperatures above 900° F. without porcelain chipping or cracking, comprising the steps of: 
 heating the oven to a temperature above 900° F., said oven containing said porcelain-coated steel wire oven rack formed by steps a)-e):    a) providing steel rod material containing from about 80 to about 99.9% by weight of iron, up to about 0.08% by weight of carbon and from about 0.001 to about 0.2% by weight of carbon stabilizing transition metal selected from the group consisting of Vanadium, Tantalum, Titanium and Niobium;    b) drawing the steel rod material to form steel wire, wherein the diameter of the cross-sectional area of the steel rod material is reduced by at least about 20% to form cavities in the steel wire in which hydrogen, emitted from the steel wire, is received and compressed at the oven cleaning temperature, without chipping or cracking the porcelain coating;    c) forming a plurality of elongated steel wire members from said steel wire;    d) joining the plurality of steel wire members to one another to form interconnected parts of a steel wire oven rack; and    e) coating the steel wire oven rack with a lubricious porcelain,    wherein the amount of carbon in the steel rod material, the amount of carbon stabilizing transition metal in the steel rod material and the degree to which the diameter of the cross-sectional area of the steel rod material is reduced, when the steel wire is drawn from the steel rod material, are selected to prevent chipping of the glass material away from the outer surface of the article due to the release of hydrogen gas from the steel wire members when the glass-coated steel wire members are heated to a temperature above 900° F.    
   
   
       40 . The method of  claim 39 , wherein the lubricious porcelain coating includes a homogeneously distributed dry lubricant selected from the group consisting of carbon; graphite; boron nitride; cubic boron nitride; molybdenum (IV) sulfide; molybdenum disulfide; molybdenum sulfide; molybdenum (IV) selenide; molybdenum selenide; tungsten (IV) sulfide; tungsten disulfide; tungsten sulfide; silicon nitride (Si 3 N 4 ); TiN; TiC; TiCN; TiO 2 ; TiAlN; CrN; SiC; diamond-like carbon; tungsten carbide (WC); zirconium oxide (ZrO 2 ); zirconium oxide and 0.1 to 40 weight % aluminum oxide; alumina-zirconia; antimony; antimony oxide; antimony trioxide; and mixtures thereof.  
   
   
       41 . The lubricious, glass-coated metal article of  claim 1 , wherein the dry refractory lubricant material is selected from the group consisting of Cr 3 C 2 ; Cr 23 C 6 ; Cr 7 C 3 ; Cr 3 C 2 ; an alloy of Mo, Cr, Si and Co; an alloy of Ni, Cr, W, Si, B, and Co; an alloy of Ni, Cr, W and Co; WC and Co; a combination of Cr 3 C 2  and NiCr; chromium carbide; and mixtures thereof.  
   
   
       42 . The lubricious, glass-coated steel article of  claim 15 , wherein the dry refractory lubricant material is selected from the group consisting of Cr 3 C 2 ; Cr 23 C 6 ; Cr 7 C 3 ; Cr 3 C 2 ; an alloy of Mo, Cr, Si and Co; an alloy of Ni, Cr, W, Si, B, and Co; an alloy of Ni, Cr, W and Co; WC and Co; a combination of Cr 3 C 2  and NiCr; chromium carbide; and mixtures thereof.  
   
   
       43 . The lubricious, glass-coated steel oven rack of  claim 26 , wherein the dry refractory lubricant material is selected from the group consisting of Cr 3 C 2 ; Cr 23 C 6 ; Cr 7 C 3 ; Cr 3 C 2 ; an alloy of Mo, Cr, Si and Co; an alloy of Ni, Cr, W, Si, B, and Co; an alloy of Ni, Cr, W and Co; WC and Co; a combination of Cr 3 C 2  and NiCr; chromium carbide; and mixtures thereof.  
   
   
       44 . The method of  claim 31 , wherein the dry refractory lubricant material is selected from the group consisting of Cr 3 C 2 ; Cr 23 C 6 ; Cr 7 C 3 ; Cr 3 C 2 ; an alloy of Mo, Cr, Si and Co; an alloy of Ni, Cr, W, Si, B, and Co; an alloy of Ni, Cr, W and Co; WC and Co; a combination of Cr 3 C 2  and NiCr; chromium carbide; and mixtures thereof.  
   
   
       45 . The method of  claim 39 , wherein the dry refractory lubricant material is selected from the group consisting of Cr 3 C 2 ; Cr 23 C 6 ; Cr 7 C 3 ; Cr 3 C 2 ; an alloy of Mo, Cr, Si and Co; an alloy of Ni, Cr, W, Si, B, and Co; an alloy of Ni, Cr, W and Co; WC and Co; a combination of Cr 3 C 2  and NiCr; chromium carbide; and mixtures thereof.