Method for manufacturing enamel layer and coated article having the same

Abstract

A method for manufacturing enamel layer includes the steps of: a substrate is provided; a spray paint is provided, the spray paint includes liquid fuel and enamel powders; providing a spraying device for spraying the spray paint, the liquid fuel of the spray paint spayed by the spraying device fires to heat and sinter the enamel powder to deposit on the substrate and form the enamel layer. The article manufactured by the method is also provided.

What is claimed is: 
     
         1 . A method for manufacturing an enamel layer, comprising:
 providing a substrate;   providing a spray paint, the spray paint comprising liquid fuel and enamel powder;   providing a spraying device for spraying the spray paint, the liquid fuel of the spray paint spayed by the spraying device firing to heat and sinter the enamel powder to deposit the enamel powder on the substrate and form the enamel layer.   
     
     
         2 . The method as claimed in  claim 1 , wherein in the spray paint, the mass ratio of the enamel powder to the liquid fuel is about 0.75:1 to about 0.85:1. 
     
     
         3 . The method as claimed in  claim 1 , wherein the liquid fuel comprises at least one selected from a group consisting of alcohol-based liquid fuel, bio-alcohol oil, and heavy oil. 
     
     
         4 . The method as claimed in  claim 3 , wherein the alcohol-based liquid fuel comprises methanol, ethanol, and water, wherein the volume percentage of the methanol is about 80% to about 90%, the volume percentage of the ethanol is about 5% to about 10%, and the volume percentage of the water is about 4% to about 6%. 
     
     
         5 . The method as claimed in  claim 3 , wherein the liquid fuel further comprises a combustion improver. 
     
     
         6 . The method as claimed in  claim 1 , wherein the enamel powder consists of silicon oxide, aluminium oxide, sodium oxide, and potassium oxide, wherein the mass percentage of the silicon oxide is about 60 to about 70%, the mass percentage of the aluminum oxide is about 15 to about 20%, the mass percentage of the sodium oxide is about 4 to about 6%, and the mass percentage of the potassium oxide is about 4 to about 6%. 
     
     
         7 . The method as claimed in  claim 6 , wherein the enamel powder further comprises at least one selected from a group consisting of ferric oxide, calcium oxide, magnesium oxide, and titanium oxide. 
     
     
         8 . The method as claimed in  claim 1 , wherein the diameter of the enamel powder is about 50 nm to about 120 nm. 
     
     
         9 . The method as claimed in  claim 1 , wherein the spraying device comprises an inner pipe, an outer pipe surrounding to the inner pipe, the inside diameter of the inner pipe is about 4.5 mm to about 6.5 mm. 
     
     
         10 . The method as claimed in  claim 9 , wherein the length of the inner pipe is about 27 cm to about 30 cm. 
     
     
         11 . The method as claimed in  claim 1 , wherein during the spraying process, the spraying amount of the spray paint is about 4 Kg/h to about 9 Kg/h, the spraying rate is about 260 m/s to about 320 m/s. 
     
     
         12 . The method as claimed in  claim 1 , wherein the enamel layer has a porosity of about 0 to about 1%. 
     
     
         13 . A coated article, comprising:
 a substrate; and   an enamel layer formed on the substrate, the enamel layer having a porosity of about 0 to about 1%, the diameter of holes formed in the enamel layer being about 100 mm to about 1000 mm.   
     
     
         14 . The coated article as claimed in  claim 13 , wherein the enamel layer consists of silicon oxide, aluminium oxide, sodium oxide, and potassium oxide, wherein the mass percentage of the silicon oxide is about 60 to about 70%, the mass percentage of the aluminum oxide is about 15 to about 20%, the mass percentage of the sodium oxide is about 4 to about 6%, and the mass percentage of the potassium oxide is about 4 to about 6%. 
     
     
         15 . The coated article as claimed in  claim 14 , wherein the enamel layer further comprises at least one selected from a group consisting of ferric oxide, calcium oxide, magnesium oxide, and titanium oxide. 
     
     
         16 . The coated article as claimed in  claim 13 , wherein the substrate is made of stainless steel, titanium alloy, or nickel-chromium alloy. 
     
     
         17 . The coated article as claimed in  claim 13 , wherein the substrate is made of ceramic.