JPH0421799A - Through defect-detecting solution - Google Patents
Through defect-detecting solutionInfo
- Publication number
- JPH0421799A JPH0421799A JP12109390A JP12109390A JPH0421799A JP H0421799 A JPH0421799 A JP H0421799A JP 12109390 A JP12109390 A JP 12109390A JP 12109390 A JP12109390 A JP 12109390A JP H0421799 A JPH0421799 A JP H0421799A
- Authority
- JP
- Japan
- Prior art keywords
- plating
- defects
- soln
- ammonia
- concentration
- 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.)
- Pending
Links
- 230000007547 defect Effects 0.000 claims abstract description 40
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000007747 plating Methods 0.000 claims abstract description 30
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 17
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 15
- 238000001514 detection method Methods 0.000 claims description 23
- 239000007788 liquid Substances 0.000 claims description 17
- 239000007864 aqueous solution Substances 0.000 claims description 14
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 13
- 230000000149 penetrating effect Effects 0.000 claims description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052802 copper Inorganic materials 0.000 claims description 9
- 239000010949 copper Substances 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 8
- 230000035515 penetration Effects 0.000 claims description 7
- 229910052804 chromium Inorganic materials 0.000 claims description 3
- 239000011651 chromium Substances 0.000 claims description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 18
- 235000019441 ethanol Nutrition 0.000 description 11
- 238000007689 inspection Methods 0.000 description 10
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 239000002131 composite material Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000009472 formulation Methods 0.000 description 3
- 229910052742 iron Inorganic materials 0.000 description 3
- 239000012085 test solution Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 230000007096 poisonous effect Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
Landscapes
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
本発明は素材の下地に銅をメッキしてなるクロムメッキ
製品の貫通ピンホールの欠陥を検出する貫通欠陥検出液
に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a penetration defect detection liquid for detecting defects in penetration pinholes in chrome-plated products made by plating copper on the base of a material.
〈従来の技術〉
例えば銅板圧延用ロールの位置制訂を目的として設置さ
れた油圧シリンダは、冷却水等の腐食環境、酸化鉄を主
体とした粉塵、等の過酷な条件に曝され、更に摺動によ
る摩耗も避けることができないため、これらの防止を目
的として、ロッドには下地に銅メッキした後、表面に硬
質クロムメッキを被覆した複合メッキが主に用いられて
いる。<Prior art> For example, hydraulic cylinders installed for the purpose of regulating the position of copper plate rolling rolls are exposed to harsh conditions such as a corrosive environment such as cooling water, dust mainly composed of iron oxide, etc. In order to prevent this, composite plating is mainly used for rods, in which the base is plated with copper and the surface is coated with hard chrome plating.
したがって、製作したシリンダーの検査では、耐摩耗性
の観点から表面硬度を、また耐食性の観点から、クロム
メッキ層から、母材に貫通した欠陥の有無が問題となる
。Therefore, when inspecting manufactured cylinders, the issue is the surface hardness from the viewpoint of wear resistance, and the presence or absence of defects penetrating the chrome plating layer into the base material from the viewpoint of corrosion resistance.
この内、表面硬度は、ショア硬さ針等を用い、容易に測
定することが可能であるが、貫通欠陥の検査は、表面を
ベールで拡大し、観察する等、目視的な方法に頼らざる
を得ない状態であった。Among these, surface hardness can be easily measured using a Shore hardness needle, etc., but inspection for penetrating defects requires visual methods such as enlarging the surface with a veil and observing it. I was in a state where I couldn't get anything.
また、このような検査方法では検査が長時間かかり、更
に貫通欠陥と、非貫通欠陥の区別ができず、結果として
必要以上に厳しい検査となり、製造コストの上昇を招く
原因の一つとなっていた。In addition, with this type of inspection method, the inspection takes a long time, and it is not possible to distinguish between through-hole defects and non-through-hole defects, resulting in an unnecessarily strict inspection, which is one of the causes of increased manufacturing costs. .
周知のように、鉄の素材上に施工したクムメッキに発生
した貫通ピンホール等の欠１はＪＩＳでも規定されてい
るように、フェオキシル試験法で検出することが可能で
あごの従来の検出方法は、素材の鉄とフェオキシル試験
液を反応させ、青色の反応生１物を検出するものである
。As is well known, defects such as penetrating pinholes that occur in Kumu plating applied to iron materials can be detected using the Feoxyl test method as specified in JIS, and the conventional detection method for jaws is , the material iron reacts with the Feoxyl test solution, and a blue reaction product is detected.
すなわち、被検査物の表面にフェオキ
シ試験液を含ませた濾紙を置けば、貫通ピホール等の欠
陥部では青色となるわけであ；〈発明が解決しようとす
る課題〉
しかし、素材の鉄表面にり四ムメッキの１着性向上等を
目的として銅を薄くメッキし、その後クロムメッキを施
工したものでは、プとえクロムメッキ層に貫通欠陥があ
っても一部のフェロオキシル試験液では鋼メッキ層”遮
断され、検出は不能であり、したがって、検査はルーパ
等を用いる目視検査が主体とメっでいた。In other words, if a filter paper impregnated with pheoxy test liquid is placed on the surface of the object to be inspected, defects such as through piholes will turn blue; For products that have been thinly plated with copper for the purpose of improving the adhesion of four-metal plating, and then chrome plating is applied, some ferrooxyl test solutions will not allow steel plating even if there are penetration defects in the chrome plating layer. The layer was blocked and detection was impossible, so the inspection was mainly done by visual inspection using a looper or the like.
このような検査方法では、検査が長時間ｆかり、更に貫
通欠陥と、非貫通欠陥との区別ができず、更に見落とし
も多い等の問題点があった。In such an inspection method, there are problems in that the inspection takes a long time, it is impossible to distinguish between through defects and non-through defects, and there are many oversights.
本発明は、以上述べた事情に鑑み、貫通ピンホールの欠
陥を検出するに当って検査精度の向上及び簡易に検出可
能な貫通欠陥検出液を提供する乙とを目的とする。In view of the above-mentioned circumstances, an object of the present invention is to provide a through-hole defect detection liquid that can improve inspection accuracy and easily detect through-pinhole defects.
く課題を解決するための手段〉
前記目的を達成するための本発明の貫通欠陥出液は、素
材の下地に銅をメッキしてなるクロムメッキの貫通ピン
ホールの欠陥を検出する貫通欠陥検出液であって、 ア
ルコールの濃度が３０％以上、５０％以下のアルコール
水溶液に、アンモニアの濃度を１０％以上、２０％以下
を混合してなることを特徴とする。Means for Solving the Problems〉 To achieve the above object, the present invention provides a through defect detection liquid for detecting defects in through pinholes in chrome plating, which is formed by plating copper on the base of the material. It is characterized in that it is made by mixing an ammonia concentration of 10% or more and 20% or less with an alcohol aqueous solution having an alcohol concentration of 30% or more and 50% or less.
以下、本発明を説明する。The present invention will be explained below.
本発明は例えば鉄等の素材の下地に銅メツキを施した後
にクロムメッキを施した複合メッキ層の貫通欠陥を検出
するアンモニアを主体とした貫通欠陥検出液である。The present invention is an ammonia-based penetrating defect detection liquid for detecting penetrating defects in a composite plating layer in which copper plating is applied to a base of a material such as iron, followed by chromium plating.
とこで本発明は、本検出液の主成分であるアンモニアが
鋼と反応して青色の主成分を生じさせるため、この性質
を利用すると共；こ、微小な欠陥に浸透させるため、高
浸透性も考慮したものであるっ
本発明では、効率よく欠陥を検出するための検出液は、
３０％す上、５０％以下のアルコール水溶液にアンモニ
アの濃度を１０％以上、２０％以下混合してなるものを
いう。However, in the present invention, since ammonia, which is the main component of this detection liquid, reacts with steel to produce a blue main component, this property is utilized; In the present invention, the detection liquid for efficiently detecting defects is
It refers to a product made by mixing an ammonia concentration of 10% or more and 20% or less in an alcohol aqueous solution of 30% or more and 50% or less.
これば第１図に示す「アシモニア水溶液濃度欠陥検出ま
での時間Ｊのグラフに示すように、アンモニア濃度が２
０％以上必要であることが判明したが、周知のようにア
ンモニアは毒ガスのため、この濃度では作業に支障をき
なすことも判明したので、防毒マスク等の特別の保護具
を使用すること無く、シかも換気のよい部屋で作業する
ための条件として、アンモニア濃度２０％以下、また作
業時間１（分以下、出来れば５分以下とするのが良いこ
とを確認した。In this case, as shown in the graph of "Asimonia aqueous solution concentration time J until defect detection" shown in Figure 1, the ammonia concentration is 2.
It was found that 0% or more was required, but as it is well known that ammonia is a poisonous gas, it was also found that this concentration would cause problems with the work, so it was not necessary to use special protective equipment such as a gas mask. We have confirmed that the conditions for working in a well-ventilated room are that the ammonia concentration is 20% or less, and the working time is 1 minute or less, preferably 5 minutes or less.
そこで、この条件を満足する方法を試験した結果、第２
図に示すように、水溶液中の水の一部をアルコールへ置
換することにより、これを満足できることが確認された
。尚、アルコール効果は、■クロームメッキとの濡れ性
の良さ、■表面等に極薄く付着している油分等の汚れに
対する濡れ性の良さ等が発揮されると考えられ、これら
の効果により、アンモニア水溶液が微細な割れ等に侵入
し、検出積度が向上したものと推察される。Therefore, as a result of testing a method that satisfies this condition, the second
As shown in the figure, it was confirmed that this can be satisfied by replacing part of the water in the aqueous solution with alcohol. The effects of alcohol are thought to include: ■ good wettability with chrome plating, and ■ good wettability with dirt such as oil that is extremely thinly attached to the surface. It is presumed that the aqueous solution penetrated into minute cracks, etc., improving the detection area.
これらより、実用的な検査液の組成は、アルコールの濃
度が３０％以上５０％以下の水溶液に、アンモニアの濃
度を１０％ｐ上２０％す下が好ましいこととなる。ここ
で、アルコールとしてはメチルアルコールが好ましいが
、エチルアルコール、プロピルアルコール等の低級アル
コールであればいずれでもよい。From these, it is preferable that the composition of a practical test liquid is an aqueous solution with an alcohol concentration of 30% or more and 50% or less, and an ammonia concentration of 10%p or more and 20% or less. Here, the alcohol is preferably methyl alcohol, but any lower alcohol such as ethyl alcohol or propyl alcohol may be used.
なお、メチルアルコールの濃度が３０％以上５０％以下
の水溶液となる理由は第２図に示す検出時間の短時間と
なる濃度から、またアンモニアの濃度を１０％以上とし
た理由は第１図に示す試験結果及び第２図に示す結果か
ら類推した短時間での欠陥検出時間から、更にアンモニ
アの濃度を２０％以下七した理由は、防毒マスク等の特
別の保護具を使用すること無く、換気のよい部屋で作業
出来るための経験条件からそれぞれ決定した。The reason why the aqueous solution has a methyl alcohol concentration of 30% to 50% is because the concentration shortens the detection time shown in Figure 2, and the reason why the ammonia concentration is 10% or more is shown in Figure 1. The reason why we set the ammonia concentration to 20% or less is based on the short defect detection time that can be inferred from the test results shown in Figure 2 and the results shown in Figure 2. Each was determined based on the experience requirements for being able to work in a comfortable room.
また、本発明の貫通欠陥検出液を用いての具体的な検査
手順は以下のようになる。Further, a specific inspection procedure using the penetrating defect detection liquid of the present invention is as follows.
■ 貫通欠陥のあるクロムメッキ無の表面に貫通欠陥検
出液を含ませた濾紙８Ｍけば該検出液が貫通欠陥無に浸
透し、銅メッキ部で反応を生じろ。(2) If an 8M filter paper impregnated with a penetrating defect detection liquid is placed on a non-chromium-plated surface with a penetrating defect, the detection liquid will penetrate into the penetrating defect and cause a reaction in the copper-plated area.
■ この反応で生じた生成物が濾紙表面に青色の反応跡
を残す。■ The products produced in this reaction leave a blue reaction mark on the surface of the filter paper.
■ 青色の反応跡の有無で貫通欠陥の有無が検出出来る
。■ The presence or absence of a penetrating defect can be detected by the presence or absence of blue reaction traces.
息上述べたように、本発明に係る貫通欠陥検出液は、素
材の下地に銅メッキしたクロムメッキ製品のクロムメッ
キ層の貫通欠陥検出に用いて、精度よく欠陥を検出でき
、特に、鋼板圧延用ロールの位置制御を目的として設置
された、表面にクロムメツ口を被覆した複合メッキ製の
油圧シリンダロッドクロムメッキ層の貫通欠陥の検出に
用して好適である。As mentioned above, the through-hole defect detection liquid according to the present invention can be used to detect through-hole defects in the chrome-plated layer of a chrome-plated product in which the underlying material is copper-plated, and can detect defects with high accuracy. The present invention is suitable for detecting penetration defects in the chrome plating layer of a hydraulic cylinder rod made of composite plating, the surface of which is coated with a chrome opening, which is installed for the purpose of controlling the position of the roll.
〈実 施 例〉
下地として銅メッキしたようにクロムメツキを被覆した
複合メッキ製の油圧シリンダロッドクロムメッキ層の約
０１−のピンホール無の貫通欠陥検出を下記配合の検出
液を用いて行った。<Example> Detection of pinhole-free penetration defects of about 01- in the chromium plating layer of a hydraulic cylinder rod made of composite plating coated with chrome plating as if copper plating was done as a base was carried out using a detection liquid of the following composition.
配−二釦ユ
３０％アンモニア水溶液 １００ｃｃ水
０ｃｃ
メチルアルコール
０ｃｃ
配 合２
３０％アンモニア水溶液
メチルアルコール
０ｃｃ
０ｃｃ
配 合３
３０％アンモニア水溶液 １００ｃｃ水
８０ｃｃメチルアルコー
ル ２０ｃｃ比較例として従来のフェロイキ
シル試験液を用いて実施した。30% ammonia aqueous solution 100cc water 0cc methyl alcohol 0cc Formulation 2 30% ammonia aqueous solution methyl alcohol 0cc 0cc Formulation 3 30% ammonia aqueous solution 100cc water
80cc methyl alcohol 20cc As a comparative example, a conventional ferrooxyl test liquid was used.
この結果を第１表に示す。The results are shown in Table 1.
第１表（単位ｃｃ）
したがって、最適の試験液配合条件は、アンモニア水溶
液濃度が１０％以上、また、エチルアルコール濃度が３
０〜４０％と判断された。Table 1 (unit: cc) Therefore, the optimal test solution formulation conditions are an ammonia aqueous solution concentration of 10% or more, and an ethyl alcohol concentration of 3%.
It was determined to be 0-40%.
〈発明の効果〉
以上、実施例と共に述へたように本発明の貫通欠陥検出
液は、メチルアルコールの濃度が３０％以上５０％以下
の水溶液に、アンモニアの濃度を１０％息上２０％以下
を混合して成るので、下地に銅メッキしたクロムメッキ
の貫通欠陥検出に用いる場合、微細な貫通ピンホール部
であっても鋭敏に反応するので検査精度が向上すると共
に極めて簡易に検出することができるという効果を奏す
る。<Effects of the Invention> As described above together with the examples, the penetration defect detection liquid of the present invention is obtained by adding an ammonia concentration of 10% to an aqueous solution having a methyl alcohol concentration of 30% or more and 50% or less and a 20% or less concentration. When used to detect through-hole defects in chrome plating with copper plating as the base, even minute through-hole pinholes can be detected sharply, improving inspection accuracy and making detection extremely easy. It has the effect of being able to do it.
第１図：よアンモニア水溶液濃度欠陥検出までの時間を
示すグラフ、第２図りよ欠陥検出時間に及ぼすアルコー
ル濃度の影響示すグラフである。
特 許 出 願 人
三菱重工業株式会社
代 理 人Fig. 1: A graph showing the concentration of ammonia aqueous solution and the time taken to detect a defect; Fig. 2: A graph showing the influence of alcohol concentration on the defect detection time. Patent applicant Mitsubishi Heavy Industries, Ltd. Agent
Claims (1)
ンホールの欠陥を検出する貫通欠陥検出液であって、 アルコールの濃度が３０％以上、５０％以下のアルコー
ル水溶液に、アンモニアの濃度を１０％以上、２０％以
下を混合してなることを特徴とする貫通欠陥検出液。[Scope of Claims] A penetration defect detection liquid for detecting defects in penetrating pinholes in chromium plating, which is made by plating copper on the base of the material, which is an alcohol aqueous solution with an alcohol concentration of 30% or more and 50% or less. A penetrating defect detection liquid characterized in that the ammonia concentration is mixed at a concentration of 10% or more and 20% or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12109390A JPH0421799A (en) | 1990-05-14 | 1990-05-14 | Through defect-detecting solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12109390A JPH0421799A (en) | 1990-05-14 | 1990-05-14 | Through defect-detecting solution |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0421799A true JPH0421799A (en) | 1992-01-24 |
Family
ID=14802705
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12109390A Pending JPH0421799A (en) | 1990-05-14 | 1990-05-14 | Through defect-detecting solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0421799A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001272389A (en) * | 2000-03-24 | 2001-10-05 | Yoshikazu Kobayashi | Method and device for determination method of copper in acid electroless tin plating |
| JP2015137899A (en) * | 2014-01-21 | 2015-07-30 | 株式会社Ihi | Inspection method of stainless steel member, and manufacturing method of stainless steel product |
-
1990
- 1990-05-14 JP JP12109390A patent/JPH0421799A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001272389A (en) * | 2000-03-24 | 2001-10-05 | Yoshikazu Kobayashi | Method and device for determination method of copper in acid electroless tin plating |
| JP2015137899A (en) * | 2014-01-21 | 2015-07-30 | 株式会社Ihi | Inspection method of stainless steel member, and manufacturing method of stainless steel product |
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