Heat Shield Component and Manufacturing Method Thereof

Abstract

A heat shield component includes a substrate, and a ceramic porous layer arranged on the substrate, the ceramic porous layer including a base body including ceramic, and pores included in the base body. Inner walls of the pores are covered with thermoplastic resin, and a porosity of the ceramic porous layer is in a range of 40% to 70%. The heat shield component can achieve high heat-insulating properties.

1 . A heat shield component comprising:
 a substrate; and   a ceramic porous layer arranged on the substrate, the ceramic porous layer including a base body including ceramic, and pores included in the base body,   wherein inner walls of the pores are covered with thermoplastic resin, and   a porosity of the ceramic porous layer is in a range of 40% to 70%.   
     
     
         2 . The heat shield component according to  claim 1 , wherein a thermal conductivity of the ceramic is 5 W/(m·K) or less, and a thermal conductivity of the ceramic porous layer is 1 W/(m·K) or less. 
     
     
         3 . The heat shield component according to  claim 1 , wherein a thermal conductivity of the ceramic is 5 W/(m·K) or less, and a thermal conductivity of the ceramic porous layer is 0.5 W/(m·K) or less. 
     
     
         4 . The heat shield component according to  claim 1 , wherein a volumetric specific heat of the ceramic porous layer is 1500 kJ/m 3 K or less. 
     
     
         5 . The heat shield component according to  claim 1 , wherein a volumetric specific heat of the ceramic porous layer is 1000 kJ/m 3 K or less. 
     
     
         6 . The heat shield component according to  claim 1 , wherein the ceramic is zirconia. 
     
     
         7 . The heat shield component according to  claim 1 , wherein the ceramic is aluminum nitride. 
     
     
         8 . The heat shield component according to  claim 1 , further comprising a cover layer including silica and covering a surface of the ceramic porous layer. 
     
     
         9 . A manufacturing method of a heat shield component, the manufacturing method comprising:
 a mixing step of mixing sol including a ceramic precursor with heat-expandable microspheres having an outer shell formed of thermoplastic resin and encapsulating a foaming agent so as to obtain a mixed solution;   a coating step of applying the mixed solution to a substrate to obtain a coated product; and   a heating step of heating the coated product to form a base body including ceramic from the ceramic precursor, and leading the heat-expandable microspheres to foam so as to form a ceramic porous layer including closed pores in the base body,   the ceramic porous layer having a porosity in a range of 40% to 70%.   
     
     
         10 . The manufacturing method of a heat shield component according to  claim 9 , wherein a temperature for heating the coated product is 280° C. or lower.