| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for predicting a corrosion rate of a metal and a prediction method of a corrosion life of a metal capable of predicting the corrosion rate and the corrosion life of the metal in a time shorter than that of the conventional one. <P>SOLUTION: This method for predicting the corrosion rate of a metal according to the present invention calculates an oxygen dissolution velocity R<SB POS="POST">O2</SB>to a water film by R<SB POS="POST">O2</SB>=α×10<SP POS="POST">-βc</SP>exp(-γT) using a salt level c in the water film attached to the surface of the metal, a temperature T and coefficients α, β, and γ; when the thickness L of the water film attached to the surface, a diffusion coefficient D of the oxygen diffusing the water film, and oxygen saturation concentration C<SB POS="POST">O2</SB><SP POS="POST">0</SP>of the water film satisfy R<SB POS="POST">O2</SB>>D×C<SB POS="POST">O2</SB><SP POS="POST">0</SP>/L, an oxygen amount N<SB POS="POST">O2</SB>per unit time reaching a metal surface and per unit area is defined as N<SB POS="POST">O2</SB>=D×C<SB POS="POST">O2</SB><SP POS="POST">0</SP>/L, when R<SB POS="POST">O2</SB>≤D×C<SB POS="POST">O2</SB><SP POS="POST">0</SP>/L, then N<SB POS="POST">O2</SB>=R<SB POS="POST">O2</SB>, and the corrosion rate Rcor is predicted by Rcor=4×N<SB POS="POST">O2</SB>×w/n by using the acquired N<SB POS="POST">O2</SB>, a molar mass w of the metal and a valence n when the metal is ionized. <P>COPYRIGHT: (C)2012,JPO&INPIT |
