JP4706489B2 - Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate - Google Patents
Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate Download PDFInfo
- Publication number
- JP4706489B2 JP4706489B2 JP2006017746A JP2006017746A JP4706489B2 JP 4706489 B2 JP4706489 B2 JP 4706489B2 JP 2006017746 A JP2006017746 A JP 2006017746A JP 2006017746 A JP2006017746 A JP 2006017746A JP 4706489 B2 JP4706489 B2 JP 4706489B2
- Authority
- JP
- Japan
- Prior art keywords
- metal
- corrosion
- corrosion resistance
- corrosion rate
- thickness
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Landscapes
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
Description
本発明は、腐食環境において使用される金属および被覆金属板の寿命を予測する耐食性予測方法に関する。 The present invention relates to a corrosion resistance prediction method for predicting the life of metals and coated metal plates used in corrosive environments.
近年、自動車や建築物、家電製品などの商品の長寿命化やライフサイクルコストを最小化することが社会的に求められている。構造体としての要求寿命と同等の耐久性が、それらに使用される材料に対しても求められる。上述構造体に使用される材料の耐久性のうち耐食性に関しては、一般に各種の腐食促進試験や暴露試験によって評価が行われる。
しかし、これらの試験は実使用環境との相関が曖昧であるため、実際の耐用年数を決定することができなかった。
In recent years, there has been a social demand for extending the life of products such as automobiles, buildings, and home appliances and minimizing life cycle costs. Durability equivalent to the required life as a structure is also required for the materials used for them. Of the durability of the materials used for the structure, the corrosion resistance is generally evaluated by various corrosion acceleration tests and exposure tests.
However, since these tests have a vague correlation with the actual usage environment, the actual useful life could not be determined.
一方非特許文献１には、実環境下で長期間走行する自動車の腐食事例を多数収集し、ニューラルネットワーク非線形多変量解析手法により腐食現象を定量解析し、目標防錆年数に見合う防錆仕様を選択することが記載されている。しかしこの手法によりさび発生の予測については高い正当率が示されたものの、防錆鋼板の種類やめっき付着量等の材料を決定する手法にはなっていない。 On the other hand, Non-Patent Document 1 collects many corrosion cases of automobiles that run for a long time in a real environment, quantitatively analyzes the corrosion phenomenon using a neural network nonlinear multivariate analysis method, and provides a rust prevention specification that matches the target rust prevention years. The selection is described. However, although this method showed a high validity rate for the prediction of rust generation, it is not a method for determining materials such as the type of rust-proof steel plate and the amount of plating.
実使用環境、構造における材料の耐食寿命を予測する、あるいは要求される耐食寿命を過不足無く満足する材料の設計が必要とされている。
実環境に近い環境に試験片を暴露して、試験片の腐食量から耐食寿命を推定する方法では、自動車や建築物などの構造体に使用する材料を対象とした場合、何十年という長期にわたる試験期間を必要とする。また、過去の暴露データが存在しても、試験片と実構造物の複雑な構造とには単純な相関関係があるわけではなく、従来の暴露試験では、実構造体の耐食寿命を予測することは難しいという問題があった。 The method of estimating the corrosion resistance life from the amount of corrosion of a test piece by exposing the test piece to an environment close to the actual environment is a long period of several decades when targeting materials used in structures such as automobiles and buildings. Requires an extended test period. In addition, even if past exposure data exists, there is no simple correlation between the specimen and the complex structure of the actual structure, and the conventional exposure test predicts the corrosion resistance life of the actual structure. There was a problem that it was difficult.
また、長期間使用した実構造物の腐食の実態を調査することにより材料の耐食寿命を推定することが行われている。しかし、実構造物が腐食するには長時間を要するばかりでなく、調査に要する期間や費用が膨大になるという問題がある。
一方、前記の非特許文献１をはじめとして材料の耐食性を評価するために、従来から各種腐食促進試験法が規格化あるいは新試験法が提案されてきているが、実環境と腐食機構が異なっているばかりでなく、相関が曖昧であり、ひどいものでは材料間の耐食性の序列が逆転するという欠点がある。
In addition, the corrosion resistance life of materials is estimated by investigating the actual state of corrosion of actual structures that have been used for a long time. However, there is a problem that not only it takes a long time for the actual structure to corrode, but also the time and cost required for the survey become enormous.
On the other hand, various corrosion acceleration test methods have been standardized or new test methods have been proposed in order to evaluate the corrosion resistance of materials including the above-mentioned Non-Patent Document 1, but the actual environment differs from the corrosion mechanism. In addition, the correlation is ambiguous, and the worst is that the order of corrosion resistance between materials is reversed.
本発明は、上記のような課題を解決するためになされたものであり、実環境、構造における材料の耐食寿命を予測するものであり、その耐食寿命予測により予測された材料、およびその材料を組み込んだ商品を提供することを目的とする。 The present invention has been made to solve the above-described problems, and is intended to predict the corrosion resistance life of a material in a real environment or structure. The purpose is to provide embedded products.
本発明の要旨は、以下のとおりである。
（１）実環境における腐食速度が既知の２種の金属Ａ、Ｂと、実環境における腐食速度が未知の金属Ｃについてそれぞれ複数の腐食試験環境において腐食速度または耐食時間を求める第１の工程と、
前記金属Ａを基準金属として、この基準金属に対する金属Ｂの腐食速度比を実環境と前記複数の腐食試験環境について求める第２の工程と、
前記金属Ｃについて、前記第１の工程の結果より前記複数の腐食試験環境における腐食速度または耐食時間を求めて、基準金属に対する腐食速度比または耐食時間比を求める第３の工程と、
前記第２の工程で得られた基準金属に対する金属Ｂの腐食速度比と、第３の工程で得られた基準金属に対する金属Ｃの腐食速度比または耐食時間比との相関を求め、この相関関係から実環境における基準金属に対する金属Ｃの腐食速度比または耐食時間比を求めることにより金属Ｃの実環境における腐食速度または耐食時間を予測する第４の工程と、
を有することを特徴とする金属の耐食性予測方法。
The gist of the present invention is as follows.
(1) a first step of obtaining a corrosion rate or corrosion resistance time in a plurality of corrosion test environments for two types of metals A and B with known corrosion rates in the actual environment and a metal C with unknown corrosion rates in the actual environment; ,
A second step of using the metal A as a reference metal and determining a corrosion rate ratio of the metal B to the reference metal for an actual environment and the plurality of corrosion test environments;
For the metal C, a third step for obtaining a corrosion rate or corrosion resistance time ratio with respect to a reference metal by obtaining a corrosion rate or corrosion resistance time in the plurality of corrosion test environments from the result of the first step;
Correlation between the corrosion rate ratio of metal B to the reference metal obtained in the second step and the corrosion rate ratio or corrosion resistance ratio of metal C to the reference metal obtained in the third step is obtained, and this correlation is obtained. A fourth step of predicting the corrosion rate or corrosion resistance time of the metal C in the actual environment by determining the corrosion rate ratio or corrosion resistance ratio of the metal C to the reference metal in the actual environment from
A method for predicting corrosion resistance of a metal, characterized by comprising:
（２）基準金属である金属Ａが鋼、金属Ｂが亜鉛であり、金属Ｃが亜鉛含有合金である（１）に記載の金属の耐食性予測方法。
（３）基準金属である金属Ａが鋼、金属Ｂが亜鉛または亜鉛めっきであり、金属Ｃが表面処理層を含む亜鉛含有合金または亜鉛含有合金めっきであり、
前記第１の工程において求められる金属Ｃの腐食速度または耐食時間が、表面処理層と亜鉛含有合金または亜鉛含有合金めっきとの平均の腐食速度または合計の耐食時間である（１）に記載の金属の耐食性予測方法。
(2) The metal corrosion resistance prediction method according to (1), wherein metal A as a reference metal is steel, metal B is zinc, and metal C is a zinc-containing alloy.
(3) The metal A which is a reference metal is steel, the metal B is zinc or zinc plating, the metal C is a zinc-containing alloy or zinc-containing alloy plating including a surface treatment layer,
The metal according to (1), wherein the corrosion rate or corrosion resistance time of the metal C required in the first step is an average corrosion rate or total corrosion resistance time between the surface treatment layer and the zinc-containing alloy or the zinc-containing alloy plating. Corrosion resistance prediction method.
（４）基準金属である金属Ａが鋼、金属Ｂが亜鉛であり、金属Ｃが表面処理層である（１）に記載の金属の耐食性予測方法。
（５）前記表面処理層が、塗膜、有機皮膜、無機皮膜、有機無機複合皮膜、拡散層、から選ばれる１以上である（３）または（４）に記載の金属の耐食性予測方法。
（６）（１）ないし（５）のいずれかに記載の金属の耐食性予測方法により求めた金属Ｃの腐食速度または耐食時間を用いて、以下の式により、金属Ａが金属Ｃにより被覆されてなる被覆金属板の耐食寿命を求めることを特徴とする被覆金属板の耐食性予測方法。
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）
(4) The metal corrosion resistance prediction method according to (1), wherein metal A as a reference metal is steel, metal B is zinc, and metal C is a surface treatment layer.
(5) The metal corrosion resistance prediction method according to (3) or (4), wherein the surface treatment layer is one or more selected from a coating film, an organic film, an inorganic film, an organic-inorganic composite film, and a diffusion layer.
(6) The metal A is coated with the metal C according to the following formula using the corrosion rate or corrosion time of the metal C obtained by the method for predicting corrosion resistance of the metal according to any one of (1) to (5). A method for predicting the corrosion resistance of a coated metal sheet, comprising: obtaining a corrosion resistance life of the coated metal sheet.
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
（７）（１）ないし（５）のいずれかに記載の金属の耐食性予測方法により求めた金属Ｃの腐食速度または耐食時間と、金属Ａが金属Ｃにより被覆されてなる被覆金属板の設定された耐食寿命と、下地金属（金属Ａ）の厚さとを用いて、以下の式により、被覆層（金属Ｃ）の厚さを決定することを特徴とする被覆金属板の選定方法。
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）
(7) Corrosion rate or corrosion time of metal C obtained by the method for predicting corrosion resistance of metal according to any one of (1) to (5), and a coated metal plate in which metal A is coated with metal C are set. A method for selecting a coated metal plate, wherein the thickness of the coating layer (metal C) is determined by the following formula using the corrosion resistance life and the thickness of the base metal (metal A).
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
（８）（１）ないし（５）のいずれかに記載の金属の耐食性予測方法により求めた金属Ｃの腐食速度または耐食時間と、金属Ａが金属Ｃにより被覆されてなる被覆金属板の設定された耐食寿命と、被覆層（金属Ｃ）の厚さとを用いて、以下の式により、下地金属（金属Ａ）の厚さを決定することを特徴とする被覆金属板の選定方法。
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）
（９）被覆金属板が自動車、建材、家電製品の部材として使用されることを特徴とする（７）または（８）に記載の被覆金属板の選定方法。
(8) Corrosion rate or corrosion time of metal C obtained by the method for predicting corrosion resistance of metal according to any one of (1) to (5), and a coated metal plate formed by coating metal A with metal C are set. A method for selecting a coated metal plate, wherein the thickness of the base metal (metal A) is determined by the following formula using the corrosion resistance life and the thickness of the coating layer (metal C).
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
(9) The method for selecting a coated metal plate according to (7) or (8), wherein the coated metal plate is used as a member of an automobile, a building material, or a home appliance.
（１０）被覆金属板が自動車に塗装若しくは無塗装で使用される内板、外板、フレーム、ピラー、メンバー、補強部材（リンフォースやビームなど）、ケース、排気系部品として使用されることを特徴とする（７）または（８）に記載の被覆金属板の選定方法。 (10) The coated metal plate is used as an inner plate, an outer plate, a frame, a pillar, a member, a reinforcing member (such as reinforcement or beam), a case, or an exhaust system part used in automobiles with or without painting. The method for selecting a coated metal plate according to (7) or (8), which is characterized .
本発明の耐食性予測方法によれば、実構造において長時間使用されてきた腐食速度が既知の２種以上の金属の腐食速度を基準に、実環境・実構造体において耐食性が未知な金属（めっき、拡散層、塗膜、有機皮膜、無機皮膜、有機無機複合皮膜などの被覆層を含む）について、短期間の腐食促進試験により実環境・実構造体における未知な金属の腐食速度および耐食時間を精度よく推定することが可能となり、また耐食寿命を計算に入れた実構造の寿命設計が可能となり、最近求められているライフサイクルコスト寿命技術に寄与することが可能となる。 According to the corrosion resistance prediction method of the present invention, a metal (plating) whose corrosion resistance is unknown in the actual environment and the actual structure is based on the corrosion rates of two or more types of metals whose corrosion rates have been used for a long time in the actual structure. , Diffusion layers, coatings, organic coatings, inorganic coatings, organic-inorganic composite coatings, and other coating layers), the corrosion rate and corrosion resistance of unknown metals in real environments and actual structures can be determined through short-term corrosion acceleration tests. It is possible to estimate with high accuracy, and it is possible to design a life of an actual structure that takes the corrosion resistance life into account, thereby contributing to the recently demanded life cycle cost life technology.
図１は本発明の実施形態に係る金属および被覆層の耐食性予測方法、その金属、被覆層および構造体の設計方法、さらにその製造方法の処理過程までをフローチャート化したものである。
（ＳＴ１）：はじめに製品条件が提示される。製品条件とは、例えば腐食環境（使用地域、構造、部位など）や材料条件（許容腐食量、許容腐食穴深さ、許容塗膜膨れ幅、下地金属や被覆層の厚みや種類など）である。
FIG. 1 is a flowchart showing a method for predicting corrosion resistance of a metal and a coating layer according to an embodiment of the present invention, a method for designing the metal, the coating layer and the structure, and a process of the manufacturing method.
(ST1): First, product conditions are presented. Product conditions include, for example, the corrosive environment (use area, structure, site, etc.) and material conditions (allowable corrosion amount, allowable corrosion hole depth, allowable coating blister width, base metal and coating layer thickness and type, etc.) .
（ＳＴ２）：実環境での腐食速度が未知の金属について耐食寿命を予測する工程であり、次の（ＳＴ２−１）ないし（ＳＴ２−４）から構成される。
ここで耐食寿命を予測する、若しくは予測するために腐食速度を求める金属としては、図２に示すように、（ａ）下地となる金属単体、（ｂ）下地金属に塗膜、有機皮膜、無機皮膜、有機無機複合皮膜、拡散層、から選ばれる表面処理層、めっきなどで構成される単層の被覆層を有するもの、または（ｃ）下地金属に前記の多層の被覆層を有するものがある。被覆層に非金属の成分を有するものを含め、（ｂ）、（ｃ）を合わせて以下「被覆金属板」という。
(ST2): This is a step of predicting the corrosion resistance life of a metal whose corrosion rate in the actual environment is unknown, and is composed of the following (ST2-1) to (ST2-4).
Here, as shown in FIG. 2, the metal for which the corrosion resistance life is predicted or the corrosion rate is calculated is as follows: (a) a single metal as a base, (b) a coating on the base metal, an organic film, an inorganic There is a surface treatment layer selected from a film, an organic-inorganic composite film, a diffusion layer, a single-layer coating layer composed of plating, or (c) a base metal having the above-mentioned multilayer coating layer . Including those having a non-metallic component in the coating layer, (b) and (c) are collectively referred to as “coated metal plate” hereinafter.
（ＳＴ２−１）：寿命予測を行うためのデータを揃える工程であり、実環境における腐食速度が既知の２種の金属（以下金属Ａ、Ｂとする）と、実環境における腐食速度が未知の金属（以下金属Ｃ）について複数の腐食試験を実施し、それぞれについて腐食速度または耐食時間を求める。腐食速度とは、例えば図３に示すように、ある時間腐食試験を実施して、得られた腐食量を単位時間の腐食量に換算した値をいう。また耐食時間とは、設定された腐食量に到達するまでの時間をいう。金属Ｃは、前記したように非金属成分をも含む場合がある。また金属Ｃは複数種の金属の代表であり、１種類である必要はない。 (ST2-1): This is a process of preparing data for life prediction, and two types of metals with known corrosion rates in the real environment (hereinafter referred to as metals A and B) and the corrosion rates in the real environment are unknown. A plurality of corrosion tests are performed on the metal (hereinafter referred to as metal C), and the corrosion rate or corrosion resistance time is determined for each. For example, as shown in FIG. 3, the corrosion rate refers to a value obtained by conducting a corrosion test for a certain time and converting the obtained corrosion amount into a corrosion amount per unit time. Further, the corrosion resistance time is a time required to reach a set amount of corrosion. The metal C may contain a nonmetallic component as described above. The metal C is a representative of a plurality of types of metals, and need not be one type.
（ＳＴ２−２）：上記腐食試験を実施した金属のうち、製品に使用された実績などから実環境における腐食速度が既知の２種の金属Ａ、Ｂについて、金属Ａを基準金属とし、これに対する金属Ｂの腐食速度比を実環境と複数の腐食試験環境についてそれぞれ求める。
（ＳＴ２−３）：開発されて間がないなどの理由により実環境における腐食速度が未知の金属Ｃについて、複数の腐食試験環境における前記（ＳＴ２−２）の基準金属に対する腐食速度比または耐食時間比を求める。
(ST2-2): Among the metals subjected to the above corrosion test, with respect to the two types of metals A and B whose corrosion rates in the actual environment are known from the results used for products, etc., the metal A is the reference metal. The corrosion rate ratio of metal B is determined for each of the actual environment and a plurality of corrosion test environments.
(ST2-3): Corrosion rate ratio or corrosion resistance time with respect to the reference metal of (ST2-2) in a plurality of corrosion test environments with respect to the metal C whose corrosion rate in the actual environment is unknown due to reasons such as short development. Find the ratio.
（ＳＴ２−４）：上記（ＳＴ２−２）で求めた腐食速度比または耐食時間比と（ＳＴ２−３）で求めた腐食速度比または耐食時間比との相関を求め、この相関関係から実環境における金属Ｃの基準金属に対する腐食速度比または耐食時間比を予測する。例えば腐食試験の結果から得られた相関の回帰曲線を実環境に外挿することにより、実環境における金属Ｃの基準金属に対する腐食速度比または耐食時間比を求め、得られた腐食速度または耐食時間比から耐食寿命を予測する。 (ST2-4): Correlation between the corrosion rate ratio or corrosion resistance ratio obtained in (ST2-2) above and the corrosion rate ratio or corrosion resistance ratio obtained in (ST2-3) is obtained, and the actual environment is determined from this correlation. Corrosion rate ratio or corrosion resistance time ratio of metal C to reference metal is estimated. For example, by extrapolating the correlation regression curve obtained from the results of the corrosion test to the actual environment, the corrosion rate ratio or corrosion resistance ratio of metal C to the reference metal in the actual environment is obtained, and the obtained corrosion rate or corrosion resistance time is obtained. The corrosion-resistant life is predicted from the ratio.
たとえば図４に示すように、実環境下で腐食速度が既知である金属Ｂの基準金属に対する腐食速度比を各腐食試験について横軸にプロットし、各プロット位置に縦線を引く。つぎに実環境下で腐食速度が未知である金属Ｃの基準金属に対する腐食速度比を各腐食試験について縦線にプロットすると、図４の白丸のようなカーブが描かれ、矢印に示すように実環境下における腐食速度比の値（黒丸で示す）が推定できる。 For example, as shown in FIG. 4, the corrosion rate ratio of the metal B, whose corrosion rate is known in the actual environment, to the reference metal is plotted on the horizontal axis for each corrosion test, and a vertical line is drawn at each plot position. Next, when the corrosion rate ratio of metal C, whose corrosion rate is unknown in the actual environment, to the reference metal is plotted on a vertical line for each corrosion test, a curve like the white circle in FIG. The value of the corrosion rate ratio under the environment (indicated by black circles) can be estimated.
腐食速度を予測した金属が被覆層である場合、被覆金属板の腐食速度と耐食寿命の関係は、図５のように示すことができる。すなわち、全体の腐食期間は被覆層の腐食期間と、下地金属の腐食期間との和であり、つぎの式（１）
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度） ・・・（１）
を用いて耐食寿命を決定することができる。なお、この式の右辺第１項は被覆層（金属Ｃ）の耐食時間である。
When the metal whose corrosion rate is predicted is a coating layer, the relationship between the corrosion rate of the coated metal plate and the corrosion resistance life can be shown as shown in FIG. That is, the total corrosion period is the sum of the corrosion period of the coating layer and the corrosion period of the base metal, and the following equation (1)
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A) (1)
Can be used to determine the corrosion resistance life. The first term on the right side of this formula is the corrosion resistance time of the coating layer (metal C).
なお、以上腐食速度から耐食寿命を求める場合について説明したが、耐食時間を用いて耐食寿命を求める場合には、つぎに示す式（２）を前記の式（１）に代入することにより式（３）が得られ、これを用いて耐食寿命を決定することができる。
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）
・・・（２）
耐食寿命＝被覆層（金属Ｃ）の耐食時間＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度） ・・・（３）
また、耐食時間はつぎに示す式（４）によっても求めることができ、これを前記の式（３）に代入して耐食寿命を決定することができる。
In addition, although the case where the corrosion resistance life is obtained from the corrosion rate has been described above, when the corrosion resistance life is obtained using the corrosion resistance time, the following equation (2) is substituted into the above equation (1) to obtain an equation ( 3) is obtained, which can be used to determine the corrosion resistance life.
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
... (2)
Corrosion resistance = Corrosion resistance time of coating layer (metal C) + (thickness of base metal (metal A) / corrosion rate of metal A) (3)
Further, the corrosion resistance time can also be obtained by the following equation (4), which can be substituted into the above equation (3) to determine the corrosion resistance life.
被覆層（金属Ｃ）の耐食時間＝（金属Ｃに相当する耐食性を有する金属Ｂの厚さ／金属Ｂの腐食速度） ・・・（４）
ここで、金属Ｃに相当する耐食性を有する金属Ｂの厚さは、腐食試験の結果から得られた厚みを変えた金属Ｂの腐食量、または同じく厚みを変えた金属Ｂを被覆層とした金属Ａの腐食量と、金属Ｂの厚さとの相関関係と、金属Ｃの腐食量または金属Ｃを被覆層とした金属Ａの腐食量から求めることができる。
Corrosion resistance time of coating layer (metal C) = (thickness of metal B having corrosion resistance corresponding to metal C / corrosion rate of metal B) (4)
Here, the thickness of the metal B having corrosion resistance corresponding to the metal C is the amount of corrosion of the metal B obtained by changing the thickness obtained from the result of the corrosion test, or the metal having the same thickness as the coating layer. It can be determined from the correlation between the corrosion amount of A and the thickness of the metal B and the corrosion amount of the metal C or the corrosion amount of the metal A using the metal C as a coating layer.
また、各金属の厚さは、長さの値を用いればよいが、被覆層とする場合には、付着量（単位面積当たりの質量）に換算した値を用いてもよい。
（ＳＴ３）：以上の（ＳＴ２−１）ないし（ＳＴ２−４）の処理により求めた材料の腐食寿命が、要求される耐用年数を満足するか否かを判断して、製品に使用する材料を選定する。
The thickness of each metal may be a value of length, but in the case of a coating layer, a value converted into an adhesion amount (mass per unit area) may be used.
(ST3): It is determined whether the corrosion life of the material obtained by the above processes (ST2-1) to (ST2-4) satisfies the required service life, and the material used for the product is determined. Select.
要求される耐用年数を満足するように材料を設計して、製品の構造部材として選定してもよい。例えば、上記被覆金属板の腐食速度と耐食寿命の関係式において、耐食寿命と下地金属の腐食許容厚さが既知である場合は被覆層の厚さを、耐食寿命と被覆層の腐食許容厚さが既知の場合は下地金属の厚さを決定することにより、金属および被覆層の厚さや下地金属の厚さを決定することができる。 The material may be designed to satisfy the required service life and selected as a structural member of the product. For example, in the relational expression between the corrosion rate of the coated metal plate and the corrosion resistance life, if the corrosion resistance life and the allowable corrosion thickness of the base metal are known, the thickness of the coating layer is set to the corrosion resistance life and the allowable corrosion thickness of the coating layer. Is known, the thickness of the metal and the coating layer and the thickness of the base metal can be determined by determining the thickness of the base metal.
耐用年数を満足する金属Ｃが存在しない場合には、本発明の寿命予測方法を用いて新たに設計する。
上記のように決定された被覆金属板は、自動車、建材、家電製品の部材として使用されることが好ましい。特に自動車に塗装もしくは無塗装で使用される内板、外板、フレーム、ピラー、メンバー、補強部材（リンフォース、ビームなど）、ケース、排気系部品として使用されることが好ましい。
When there is no metal C that satisfies the service life, a new design is performed using the life prediction method of the present invention.
The coated metal plate determined as described above is preferably used as a member for automobiles, building materials, and home appliances. In particular, it is preferably used as an inner plate, an outer plate, a frame, a pillar, a member, a reinforcing member (reinforce, a beam, etc.), a case, and an exhaust system component that are used in automobiles with or without painting.
（実施例１）
表１は、４種類の金属について、３種類の従来腐食試験機および実環境下での腐食速度を求めた結果である。ここでは、下地金属である鋼板（記号Ｆｅとする、以下同様）および亜鉛めっき（Ｚｎ）が実環境下において実績があり、Ｚｎ含有合金めっき（ＺＡ）単層と有機皮膜を有する亜鉛含有合金めっき（ＯＺＡ）についてこれまで実環境下での使用実績がなく、腐食速度が不明であった。
Example 1
Table 1 shows the results of determining the corrosion rates under three types of conventional corrosion test machines and actual environments for the four types of metals. Here, a steel plate (symbol Fe, hereinafter the same) and zinc plating (Zn), which are the base metals, have a track record in actual environments, and a zinc-containing alloy plating having a Zn-containing alloy plating (ZA) single layer and an organic film. (OZA) has not been used in actual environments so far, and the corrosion rate was unknown.
３種類の腐食試験および実環境下において、腐食環境が変化することによる各金属の腐食速度の変化に一様の決まりなく、従来、各種腐食試験単独、若しくは鋼や亜鉛など使用実績のある金属の腐食速度との関係から、亜鉛合金や有機皮膜を有する亜鉛含有合金めっきなどの実環境における腐食速度が未知の金属について、腐食速度や耐食寿命を予測することはできなかった（寿命判定×）。 In the three types of corrosion tests and in the actual environment, the change in the corrosion rate of each metal due to the change in the corrosive environment is not uniform. From the relationship with the corrosion rate, the corrosion rate and corrosion resistance life could not be predicted for metals with unknown corrosion rate in the real environment, such as zinc alloy and zinc-containing alloy plating with organic coating (life determination ×).
（実施例２）
表２は本発明における実施形態（ＳＴ２−２）および（ＳＴ２−３）の処理により、実施例１で得られた結果を整理したものである。４種類の金属のうち鋼を基準金属として、他の３種類の金属との腐食速度比を求めた。
(Example 2)
Table 2 summarizes the results obtained in Example 1 by the processing of the embodiments (ST2-2) and (ST2-3) in the present invention. Of the four types of metals, steel was used as the reference metal, and the corrosion rate ratio with the other three types of metals was determined.
この腐食速度比について実環境下での腐食速度が既知の鋼と亜鉛めっきＺｎの腐食速度比を横軸に取り、図４で説明した手法によって、他の金属の腐食速度比をプロットし、実環境下における腐食速度を予測したのが図６である。表２にはその予測値（［ ］で示す）が記入してある。
予測結果は、その後実施した実環境下において測定された亜鉛含有合金めっきおよび有機皮膜を有する亜鉛含有合金めっきの腐食速度と鋼の腐食速度比の値と良く対応しており（判定◎）、腐食試験の結果から実環境下における亜鉛含有合金めっきおよび有機皮膜を有する亜鉛含有合金めっきの腐食速度を予測できることが示された。
With respect to this corrosion rate ratio, the corrosion rate ratio between steel and galvanized Zn with known corrosion rates in the actual environment is plotted on the horizontal axis, and the corrosion rate ratios of other metals are plotted using the method described in FIG. FIG. 6 shows a prediction of the corrosion rate under the environment. Table 2 shows the predicted values (indicated by []).
The prediction results correspond well with the values of the corrosion rate ratio of the zinc-containing alloy plating and the zinc-containing alloy plating with an organic coating, which were measured in the actual environment, and the corrosion rate ratio of the steel (determination ◎). The test results show that the corrosion rate of zinc-containing alloy plating and zinc-containing alloy plating with organic coating can be predicted in the actual environment.
Claims (10)
前記金属Ａを基準金属として、この基準金属に対する金属Ｂの腐食速度比を実環境と前記複数の腐食試験環境について求める第２の工程と、
前記金属Ｃについて、前記第１の工程の結果より前記複数の腐食試験環境における腐食速度または耐食時間を求めて、基準金属に対する腐食速度比または耐食時間比を求める第３の工程と、
前記第２の工程で得られた基準金属に対する金属Ｂの腐食速度比と、第３の工程で得られた基準金属に対する金属Ｃの腐食速度比または耐食時間比との相関を求め、この相関関係から実環境における基準金属に対する金属Ｃの腐食速度比または耐食時間比を求めることにより金属Ｃの実環境における腐食速度または耐食時間を予測する第４の工程と、
を有することを特徴とする金属の耐食性予測方法。 A first step of determining a corrosion rate or a corrosion resistance time in a plurality of corrosion test environments for two types of metals A and B with known corrosion rates in the actual environment and a metal C with unknown corrosion rates in the actual environment;
A second step of using the metal A as a reference metal and determining a corrosion rate ratio of the metal B to the reference metal for an actual environment and the plurality of corrosion test environments;
For the metal C, a third step for obtaining a corrosion rate or corrosion resistance time ratio with respect to a reference metal by obtaining a corrosion rate or corrosion resistance time in the plurality of corrosion test environments from the result of the first step;
Correlation between the corrosion rate ratio of metal B to the reference metal obtained in the second step and the corrosion rate ratio or corrosion resistance ratio of metal C to the reference metal obtained in the third step is obtained, and this correlation is obtained. A fourth step of predicting the corrosion rate or corrosion resistance time of the metal C in the actual environment by determining the corrosion rate ratio or corrosion resistance ratio of the metal C to the reference metal in the actual environment from
A method for predicting corrosion resistance of a metal, characterized by comprising:
前記第１の工程において求められる金属Ｃの腐食速度または耐食時間が、表面処理層と亜鉛含有合金または亜鉛含有合金めっきとの平均の腐食速度または合計の耐食時間である請求項１に記載の金属の耐食性予測方法。 The metal A as the reference metal is steel, the metal B is zinc or zinc plating, the metal C is a zinc-containing alloy or zinc-containing alloy plating including a surface treatment layer,
2. The metal according to claim 1, wherein the corrosion rate or corrosion resistance time of the metal C required in the first step is an average corrosion rate or total corrosion resistance time between the surface treatment layer and the zinc-containing alloy or zinc-containing alloy plating. Corrosion resistance prediction method.
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度） A coated metal obtained by coating metal A with metal C according to the following formula using the corrosion rate or corrosion time of metal C obtained by the method for predicting corrosion resistance of metal according to any one of claims 1 to 5. A method for predicting the corrosion resistance of a coated metal sheet, wherein the corrosion resistance life of the sheet is obtained.
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度） 6. Corrosion rate or corrosion resistance time of metal C obtained by the method for predicting corrosion resistance of metal according to any one of claims 1 to 5, and a set corrosion resistance life of a coated metal plate in which metal A is coated with metal C And the thickness of the base metal (metal A), and the thickness of the coating layer (metal C) is determined by the following equation.
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
耐食寿命＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度）＋（下地金属（金属Ａ）の厚さ／金属Ａの腐食速度）
被覆層（金属Ｃ）の耐食時間＝（被覆層（金属Ｃ）の厚さ／金属Ｃの腐食速度） 6. Corrosion rate or corrosion resistance time of metal C obtained by the method for predicting corrosion resistance of metal according to any one of claims 1 to 5, and a set corrosion resistance life of a coated metal plate in which metal A is coated with metal C And the thickness of the coating layer (metal C), and the thickness of the base metal (metal A) is determined by the following equation.
Corrosion resistance life = (thickness of coating layer (metal C) / corrosion rate of metal C) + (thickness of base metal (metal A) / corrosion rate of metal A)
Corrosion resistance time of coating layer (metal C) = (thickness of coating layer (metal C) / corrosion rate of metal C)
The plate coated metal plate is used in the painting or unsubstituted painted automobile outer panel, frame, pillar, member, reinforcement member, the case, according to claim 7 or 8, characterized in that it is used as an exhaust system part To select the coated metal plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006017746A JP4706489B2 (en) | 2005-01-26 | 2006-01-26 | Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005018382 | 2005-01-26 | ||
| JP2005018382 | 2005-01-26 | ||
| JP2006017746A JP4706489B2 (en) | 2005-01-26 | 2006-01-26 | Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2006234802A JP2006234802A (en) | 2006-09-07 |
| JP4706489B2 true JP4706489B2 (en) | 2011-06-22 |
Family
ID=37042590
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006017746A Expired - Lifetime JP4706489B2 (en) | 2005-01-26 | 2006-01-26 | Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4706489B2 (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4946821B2 (en) * | 2006-12-28 | 2012-06-06 | Ｊｆｅスチール株式会社 | Method for determining structure structure |
| JP5206386B2 (en) * | 2008-12-15 | 2013-06-12 | Ｊｆｅスチール株式会社 | Corrosion promotion test method and corrosion amount prediction method for organic coated steel for civil engineering |
| JP5413293B2 (en) * | 2010-04-22 | 2014-02-12 | Ｊｆｅスチール株式会社 | Corrosion accelerated test method for heavy anti-corrosion coated steel |
| JP5510352B2 (en) * | 2010-04-22 | 2014-06-04 | Ｊｆｅスチール株式会社 | Pre-corrosion cross-section prediction method for heavy anti-corrosion coated steel materials, strength deterioration prediction method for heavy anti-corrosion coating structures, management method for heavy anti-corrosion coating structures |
| JP5413292B2 (en) * | 2010-04-22 | 2014-02-12 | Ｊｆｅスチール株式会社 | Corrosion accelerated test method for heavy anti-corrosion coated steel |
| JP5505291B2 (en) * | 2010-12-20 | 2014-05-28 | 住友電装株式会社 | Evaluation method of thermal stability and degree of deterioration of resin products |
| CN112345439B (en) * | 2020-11-26 | 2021-09-14 | 东风汽车集团有限公司 | Device and method for measuring corrosion of automobile parts |
| JP7684209B2 (en) * | 2021-12-28 | 2025-05-27 | トヨタ自動車株式会社 | A method for predicting the depth of corrosion in painted steel panels. |
| AU2024374433A1 (en) * | 2023-10-31 | 2026-02-19 | Nippon Steel Corporation | Prediction device, prediction method, and prediction program |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04183894A (en) * | 1990-11-19 | 1992-06-30 | Mitsubishi Motors Corp | Corrosion resistant steel sheet |
| JP2002328085A (en) * | 2001-02-27 | 2002-11-15 | Nkk Corp | Method for predicting corrosion life of surface-treated steel, surface-treated steel, method for designing surface-treated steel, and method for producing surface-treated steel |
| JP3665965B2 (en) * | 2001-09-11 | 2005-06-29 | Ｊｆｅスチール株式会社 | Method for selecting coated steel for peripheral part of photovoltaic power generation system, coated steel material for peripheral part of photovoltaic power generation system, and photovoltaic power generation system |
| JP2003121339A (en) * | 2001-10-11 | 2003-04-23 | Mitsubishi Heavy Ind Ltd | Method and apparatus for evaluating corrosion resistance of metallic material |
| JP2003231945A (en) * | 2002-02-12 | 2003-08-19 | Nippon Steel Corp | Al-Zn plated steel sheet with excellent corrosion resistance |
| JP2003329573A (en) * | 2002-03-08 | 2003-11-19 | Jfe Steel Kk | Method for evaluating corrosion resistance of metal material, method for predicting corrosion life of metal material, metal material, method for designing metal material, and method for manufacturing metal material |
-
2006
- 2006-01-26 JP JP2006017746A patent/JP4706489B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP2006234802A (en) | 2006-09-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| LeBozec et al. | Accelerated corrosion tests in the automotive industry: a comparison of the performance towards cosmetic corrosion | |
| JP6213426B2 (en) | Corrosion resistance evaluation method and corrosion resistance evaluation apparatus for painted metal | |
| JP4706489B2 (en) | Method for predicting corrosion resistance of metal and coated metal plate, method for selecting coated metal plate | |
| JP6436688B2 (en) | Corrosion resistance evaluation method and corrosion resistance evaluation apparatus for painted metal | |
| Diler et al. | Real‐time monitoring of the degradation of metallic and organic coatings using electrical resistance sensors | |
| Shreepathi et al. | Service life prediction of organic coatings: electrochemical impedance spectroscopy vs actual service life | |
| JP2003329573A (en) | Method for evaluating corrosion resistance of metal material, method for predicting corrosion life of metal material, metal material, method for designing metal material, and method for manufacturing metal material | |
| CN105074042A (en) | Al-Zn-based plated steel sheet | |
| Bierwagen | Corrosion and its control by coatings | |
| JP4946821B2 (en) | Method for determining structure structure | |
| JP2011227004A (en) | Method for testing corrosion acceleration of double anticorrosive coating steel material | |
| WO2006080542A1 (en) | Method of estimating corrosion resistance of metal or coated metal plate | |
| LeBozec et al. | Influence of climatic factors in cyclic accelerated corrosion test towards the development of a reliable and repeatable accelerated corrosion test for the automotive industry | |
| KR102100040B1 (en) | method of estimating at least one of coating weight and alloy degree of zinc alloy plated sheet | |
| JP2002318227A (en) | Life prediction method for surface-treated steel, surface-treated steel, design of surface-treated steel, and method of manufacturing the same | |
| JP3665965B2 (en) | Method for selecting coated steel for peripheral part of photovoltaic power generation system, coated steel material for peripheral part of photovoltaic power generation system, and photovoltaic power generation system | |
| Britner et al. | Corrosion protection for cold‐formed structural steel elements | |
| Chenoll-Mora et al. | Review and long-term corrosion analysis of coatings based on ZincAluminium-Magnesium alloys, as an alternative to traditional zincbased coatings for cable trunking systems in electrical installations | |
| Jayaraman et al. | Electrochemical Assessment of Zinc-based Anti-corrosive Solutions for Reinforced concrete structures and strategies for a Reliable Monitoring Plan | |
| CN120611544B (en) | Construction method of quantitative model for time-varying corrosion of alloy-coated steel wires in bridge cables | |
| Han et al. | Element-resolved electrochemical database: AESEC polarization curves of ZnAlMg alloy coating constituents | |
| Davidson et al. | Perforation corrosion performance of autobody steel sheet in on-vehicle and accelerated tests | |
| KR102110677B1 (en) | Method of estimating iron content of galvannealed steel | |
| KR102586135B1 (en) | Method of measuring coating adhesion amount of steel sheet | |
| Townsend et al. | License plate cosmetic corrosion test of automotive coated steel sheet |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20080925 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20101215 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20101221 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20110127 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20110215 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20110228 |