Heat shield film and method of forming heat shield film

Patent metadata

Field	Value
Publication number	US-2016201555-A1
Application number	US-201414912261-A
Country	US
Kind code	A1
Filing date	Aug 18, 2014
Priority date	Aug 22, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

A heat shield film ( 100 ) that is formed on a wall surface of an aluminum-based member (W) includes: a matrix layer ( 10 ) diffusion-bonded to the wall surface (diffusion bonding layer ( 10 ′)), having a coefficient of linear expansion of 15×10 −6 /K to 25×10 −6 /K in a temperature range of ordinary temperature to 200° C. and made of a porcelain enamel material; and hollow particles ( 20 ) dispersed in the matrix layer ( 10 ).

First claim

1 . A heat shield film comprising:
a matrix layer having a coefficient of linear expansion of 15×10 −6 /K to 25×10 −6 /K in a temperature range of ordinary temperature to 200° C. and made of a porcelain enamel material; and hollow particles dispersed in the matrix layer, wherein the heat shield film is formed on a wall surface of an aluminum-based member, and the heat shield film is diffusion-bonded to the wall surface.

2 . The heat shield film according to claim 1 , wherein
a glass transition temperature of the porcelain enamel material is lower than or equal to 400° C., and a heat-resistant temperature of the porcelain enamel material is higher than or equal to 450° C.

3 . The heat shield film according to claim 1 , wherein
the porcelain enamel material contains silica, each of the hollow particles has a silica-based outer shell, and a surface of each silica-based outer shell is modified with a hydrophilic group.

4 . The heat shield film according to claim 1 , wherein
the heat shield film has a two-layer structure of an upper layer and a base layer adjacent to the wall surface, and the base layer contains no hollow particles or contains the hollow particles in an amount smaller than that of the upper layer.

5 . A method of forming a heat shield film, comprising:
a first step of manufacturing an intermediate product formed of an aluminum-based plate and the heat shield film on a surface of the plate by applying a mixed material of hollow particles, a glass frit and a glaze onto the surface of the plate, melting the glass frit by heating, and forming the heat shield film, formed of a matrix layer and the hollow particles dispersed in the matrix layer, on the surface of the plate, the matrix layer having a coefficient of linear expansion of 15×10 −6 /K to 25×10 −6 /K in a temperature range of ordinary temperature to 200° C. and made of a porcelain enamel material; and a second step of forming the heat shield film on a wall surface of an aluminum-based member formed of a molten metal hardened portion and the plate integrated with the hardened portion by accommodating the intermediate product in a die and casting aluminum-based molten metal on the plate of the intermediate product.

6 . The method according to claim 5 , wherein
a thickness of a plate ranges from 1 mm to 2 mm.

Assignees

• Toyota Motor Co Ltd

Inventors

• Eda Akinori

Classifications

• C23D5/02

  by wet methods · CPC title

• B22D21/007

  with low melting point, e.g. Al 659 degrees C, Mg 650 degrees C · CPC title

• F02B77/11 Primary

  Thermal or acoustic insulation · CPC title

• B22D19/08

  for building-up linings or coverings, e.g. of anti-frictional metal · CPC title

• C03C8/14 Primary

  Glass frit mixtures having non-frit additions, e.g. opacifiers, colorants, mill-additions · CPC title