Metal material having excellent corrosion resistance
View Patent ↗A metal material of the present invention is composed of an underlying metal and a phosphate compound-based film which is disposed on the surface of the underlying metal and has a surface part, in which the surface part of the phosphate compound-based film contains Zr.
1. A metal material comprising:
an underlying metal; and
a phosphate compound-based film which is disposed on a surface of the underlying metal and has a surface part,
wherein the phosphate compound-based film consists of a phosphate matrix of one or more of zinc phosphate, zinc-ferrous phosphate, calcium phosphate, and iron phosphate, and a Zr phosphate and a Zr hydrogen phosphate dispersed in the phosphate matrix, and the surface part of the phosphate compound-based film contains Zr.
2. The metal material according to claim 1 ,
wherein the phosphate compound-based film contains Zr in an amount equal to or more than 1 mg/m 2 .
3. The metal material according to claim 1 ,
wherein the phosphate matrix of the phosphate compound-based film is mainly zinc phosphate.
4. The metal material according to claim 1 ,
wherein an amount equal to or more than 75% by mass of Zr contained in the phosphate compound-based film exists in an area from the surface to a depth of 50% in a thickness direction of the phosphate compound-based film.
5. The metal material according to claim 1 ,
wherein an amount of the phosphate compound-based film is equal to or more than 1 g/m 2 and equal to or less than 20 g/m 2 in terms of P.
6. The metal material according to claim 1 further comprising:
a lubricative film disposed on the phosphate compound-based film.
7. The metal material according to claim 1 , wherein a main component of the surface of the underlying metal is iron.
8. A metal material comprising:
an underlying metal;
a phosphate compound-based film disposed on a surface of the underlying metal; and
a Zr phosphate film disposed on a surface of the phosphate compound-based film,
wherein the Zr phosphate film consists of a Zr phosphate and a Zr hydrogen phosphate,
an amount of the Zr phosphate film is equal to or more than 1 mg/m 2 and equal to or less than 200 mg/m 2 in terms of Zr, and
the phosphate compound-based film is a zinc phosphate film.
9. The metal material according to claim 8 ,
wherein an amount of the phosphate compound-based film is equal to or more than 1 g/m 2 and equal to or less than 20 g/m 2 in terms of P.
10. The metal material according to claim 8 further comprising:
a lubricative film disposed on the Zr phosphate film.
11. The metal material according to claim 8 , wherein a main component of the surface of the underlying metal is iron.