JPS5839785A - Method for improving corrosion resistance of chemical equipment - Google Patents
Method for improving corrosion resistance of chemical equipmentInfo
- Publication number
- JPS5839785A JPS5839785A JP13820181A JP13820181A JPS5839785A JP S5839785 A JPS5839785 A JP S5839785A JP 13820181 A JP13820181 A JP 13820181A JP 13820181 A JP13820181 A JP 13820181A JP S5839785 A JPS5839785 A JP S5839785A
- Authority
- JP
- Japan
- Prior art keywords
- nitric acid
- corrosion resistance
- treatment
- metals
- chemical equipment
- 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
- 238000005260 corrosion Methods 0.000 title claims abstract description 30
- 230000007797 corrosion Effects 0.000 title claims abstract description 29
- 239000000126 substance Substances 0.000 title claims abstract description 15
- 238000000034 method Methods 0.000 title claims description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 21
- 229910052751 metal Inorganic materials 0.000 claims abstract description 13
- 239000002184 metal Substances 0.000 claims abstract description 13
- 150000002739 metals Chemical class 0.000 claims abstract description 12
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 7
- 238000009835 boiling Methods 0.000 claims abstract description 4
- 230000001590 oxidative effect Effects 0.000 claims abstract description 4
- -1 flITi Chemical class 0.000 claims description 2
- 239000007769 metal material Substances 0.000 claims 4
- 238000011282 treatment Methods 0.000 abstract description 18
- 238000010306 acid treatment Methods 0.000 abstract description 12
- 239000000463 material Substances 0.000 abstract description 11
- 229910052719 titanium Inorganic materials 0.000 abstract description 7
- 239000002253 acid Substances 0.000 abstract description 6
- 150000007513 acids Chemical class 0.000 abstract description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 abstract description 4
- 238000007598 dipping method Methods 0.000 abstract 2
- 230000000694 effects Effects 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 6
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 6
- 238000012360 testing method Methods 0.000 description 5
- 150000001247 metal acetylides Chemical class 0.000 description 4
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000012085 test solution Substances 0.000 description 3
- 241000270666 Testudines Species 0.000 description 2
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 229910001651 emery Inorganic materials 0.000 description 2
- 239000003112 inhibitor Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000000635 electron micrograph Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000010025 steaming Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Landscapes
- Chemical Treatment Of Metals (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、7i、zr、ra等で代表される新金属を素
材とする化学装置O耐食性向上方法に関するものである
。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for improving the corrosion resistance of chemical equipment O made from new metals such as 7i, zr, and ra.
新しい化学反応の応用が展開され、又従来の化学反応に
ついても省エネルギーや製品々質の向上尋を目的として
新しい反応条件が検討され1反応の高s化、高圧化、低
pH化等が進行し、化学プロセスにおける腐食環境は益
々厳しくな〕つつある。その為従来の耐食性鋼に代って
Ti、Z+ 。Applications of new chemical reactions are being developed, and new reaction conditions for conventional chemical reactions are being studied to save energy and improve product quality, and advances are being made to increase the s of a single reaction, increase the pressure, and lower the pH. The corrosive environment in chemical processes is becoming increasingly severe. Therefore, Ti and Z+ are used instead of conventional corrosion-resistant steel.
Ta等の所謂新金属が脚光を浴び、その適用例が増加し
つつある。ところが腐食環境は温度、圧力。So-called new metals such as Ta are in the spotlight, and their applications are increasing. However, the corrosive environment is temperature and pressure.
pH1試薬、副成物等の複合的影Wによって予想以上の
悪化を見せておシ、新金属といえども孔食等の腐食を発
生することが報告されている。新金属を素材とすb化学
#s装置の腐食、殊に孔食和ついては、へロゲンイオン
の存在する反応条件下゛においてもつとも発生し易いこ
とが確認されており。It has been reported that the complex effects of pH 1 reagents, by-products, etc. have caused more deterioration than expected, and that corrosion such as pitting corrosion occurs even with new metals. It has been confirmed that corrosion, especially pitting corrosion, of chemical #s equipment made of new metals is more likely to occur under reaction conditions in the presence of herogen ions.
へロゲン堆を触媒とする石油化学工業分野、必然的にへ
ロゲンイオンが混入してくる高温高圧廃棄物処理Vステ
ム分野*においては新金属の耐食性を向上させる必要に
迫られている。There is an urgent need to improve the corrosion resistance of new metals in the petrochemical industry, which uses helidene as a catalyst, and in the high-temperature, high-pressure waste treatment V-stem field*, where herogen ions are inevitably mixed.
本発明はこの様な事情に着目してなされた亀のであって
、Ti、Zr、Ta専の新金属を、素材の段階又は化学
装置として組立てた後の段階で。The present invention was developed in light of these circumstances, and involves the use of new metals exclusively for Ti, Zr, and Ta, either at the raw material stage or at a stage after they are assembled as chemical equipment.
その表面に硝酸処理を施すことを要Wとするものであり
、事前処理や事後%理の有無、処理温度。The surface must be treated with nitric acid, and the presence or absence of pre-treatment and post-treatment, as well as the treatment temperature.
処理時間、他の試薬との併用蛇何、硝酸濃度等について
は特段の制限を受けるものではないが、以下実験例を述
べることによって本発明の構成及び作用効果を説明し、
I!に本発明の好適条件や防食機構等について述べる。Although there are no particular restrictions on the processing time, the number of combinations with other reagents, the concentration of nitric acid, etc., the structure and effects of the present invention will be explained by describing experimental examples below.
I! The preferred conditions and anti-corrosion mechanism of the present invention will be described below.
尚特許請求の範囲に記載した実施1m様は本発明を制限
する主WOものではな(、前・後記の主旨に反しない変
更実施は全て本発明の範囲に含まれる。Note that the embodiments described in the claims are not the main WOs that limit the present invention (all changes and implementations that do not go against the gist of the preceding and following are included within the scope of the present invention.
7 i 、 Z r 、 T a等の耐食性に関する研
究は従来余り行なわれておらず試行錯誤の中から出発し
なければならなかったが一7i容器については。Research on the corrosion resistance of 7i, Zr, Ta, etc. has not been conducted in the past and had to be started through trial and error, but for 7i containers.
NaC/水溶液中にSO41N03−、Cr’+。SO41N03−, Cr’+ in NaC/aqueous solution.
po4−停のイオンを添加することによってTi。Ti by adding po4-stop ions.
孔食が抑制され、ZIC′)いて−804*によって孔
食が抑制されるとの報告がある。しかるにこれらの報告
は、へロゲンイオンを含む反応液中に孔食Oインヒビタ
ーとして前記イオン類を加えるものであるから反応液が
これらインヒビターで汚染され化学ff応の進行や製品
々質jc悪影響を汲ぼすということが心配される。そこ
で本発明者等は、化学装置におけるTi 、Zr 、T
I尋の素材を化学的処理によって予め耐食性を高める必
要があると考え、以下述べる様な検討に入った。It has been reported that pitting corrosion is suppressed by ZIC') and -804*. However, these reports involve adding the aforementioned ions as pitting corrosion O inhibitors to the reaction solution containing herogen ions, which may cause the reaction solution to be contaminated with these inhibitors and have an adverse effect on the progress of the chemical reaction and the quality of the products. There are concerns that this will happen. Therefore, the present inventors investigated the use of Ti, Zr, and T in chemical equipment.
We thought that it was necessary to improve the corrosion resistance of the I-fatty material by chemically treating it, and began the study described below.
まず試料として、工業用の7i及びzrからなる矩形片
(20m X 20 wm X 1 fl)を準備し―
そ〇一端にリード編を溶接した。次に1−を有効表面積
として残し、残部をフッ紫系樹脂で被覆して試料電極と
した。First, a rectangular piece (20 m x 20 wm x 1 fl) made of industrial 7i and zr was prepared as a sample.
I welded the lead to one end. Next, 1- was left as the effective surface area, and the remaining part was coated with a fluoro-violet resin to form a sample electrode.
環流冷却式コンデンサを設けた7ラスコ中に試験溶液と
して8憾Br−溶液(pH6)を入れ。A Br solution (pH 6) was placed as a test solution in a 7 flask equipped with a reflux-cooled condenser.
次いでこの中iK試試料電極対対極白金板)、照合電極
(Ag/Ag、C/1[極)を挿入し、89bB+−溶
液を沸騰させなからボテンVヨスタットヲ用い試料電極
の電位を50 mv、z=の速度でプラス側へ走査させ
、その時の電流値を読みとって第1図に模式的に示す電
位−電流曲線を求めた。そして同図におhて電流値が急
激に立上る点の電位を孔食電位としたが、孔食電位が高
いほど孔食の発生が抑制されゐので、孔食電位の高低に
よって耐食性の良し悪しを判定した。第1表はTi及び
zrの試験面をエメリー紙#120で崖に研摩しただけ
の亀の(I61)と、請研摩に続いて種々の化学的処理
を加えたもC) (JK2〜18)について夫々の孔食
電位測定結果を示すものである。第2表は試験液を沸騰
S * Ct−溶液(pH6)とした場合における試験
結果で、A19は屋1と全(同じ様に研摩のみしたもの
であシ、420〜81ti、#研摩に続いて種々の化学
的処理を加えたものである。$8表は試験液を常温の1
6嗟I−溶液(pH9)K変更した場合の結果を示すも
ので、ここではTIについても同様に試験を行なってい
る。ム86は試験片の表面をエメリー紙#400で単に
研摩しただけのものであシ、A8?〜48は請′研摩に
[いて種々の化学的処理を加えたものを夫々表わしてい
Ag5f6?第1〜1表においてO印を付したものは耐
食性の向上効果が認められるものであり、X印は耐食性
の向上効果を認めることができないものを示す。Next, insert the iK sample electrode (pair of counter electrode platinum plate) and the reference electrode (Ag/Ag, C/1 [pole) into this, and before boiling the 89bB+- solution, use a bottom Vyostat to increase the potential of the sample electrode to 50 mV. It was scanned toward the plus side at a speed of z=, and the current value at that time was read to obtain a potential-current curve schematically shown in FIG. The potential at the point where the current value rises rapidly in h in the same figure is defined as the pitting corrosion potential.The higher the pitting potential is, the more the occurrence of pitting corrosion is suppressed. judged bad. Table 1 shows Turtle (I61) in which the Ti and ZR test surfaces were simply polished with #120 emery paper, and C) (JK2-18) in which various chemical treatments were applied after sanding. The results of pitting potential measurement for each are shown. Table 2 shows the test results when the test solution was a boiling S*Ct solution (pH 6). The test solution was heated to room temperature and subjected to various chemical treatments.
This shows the results when the K of the 6-hour I solution (pH 9) was changed, and the same test was conducted here for TI as well. 86 is simply the surface of a test piece polished with #400 emery paper, A8? ~48 represent those that have been subjected to various chemical treatments after being polished.Ag5f6? In Tables 1 to 1, those marked with O are those in which the effect of improving corrosion resistance is recognized, and those marked with X are those in which the effect of improving corrosion resistance is not recognized.
第1〜8表を総合的に判定すると、硝酸で処理した試験
片では、硝酸の濃度1m度、処理(浸漬)時間、他の酸
との併用の有無にかかわらず耐食性向上効果を認めるこ
とができ、特に大気中での加熱を行なった後で硝酸処理
を加えたもの(417゜18.27,28,40,41
.42)では棒めて大きい効果が得られた。従って本発
明者等は硝#による処理さえ行なえば良いとの結論に到
達し。Comprehensive evaluation of Tables 1 to 8 shows that the corrosion resistance of test pieces treated with nitric acid was improved regardless of the nitric acid concentration of 1 mC, treatment (immersion) time, and whether or not it was used in combination with other acids. 417°18.27,28,40,41
.. 42) had a significantly greater effect. Therefore, the inventors of the present invention came to the conclusion that it is sufficient to carry out the treatment with nitric acid.
濃度、温度1時間醇については#段の条件を設定しなか
ったが、上記の効果をよシ確実なものとする為には、硝
酸濃度として2N以上、処坤蟲度としては常温以上、処
理時間としては2時間以上とすることが推奨される。向
他の酸との併用を行なうに当って使用できる酸としては
、硫酸、弗酸。We did not set the # conditions for the concentration and temperature for 1 hour brewing, but in order to ensure the above effect, the nitric acid concentration should be 2N or more, the temperature should be above room temperature, and the treatment It is recommended that the time be 2 hours or more. Acids that can be used in combination with other acids include sulfuric acid and hydrofluoric acid.
燐酸1等が例示される。又硝酸処理に先んじて行なう酸
化処理は、酸化性算囲気、例えば大気中の加熱によって
遂行されるが、好ましい加熱温度の上限は700℃であ
った。簡予備的な加熱処理を施した場合の硝酸処理条件
は幾分か緩和しても耐食性向上効果を低下させることが
なく、硝酸濃度2N、地理温度20″C1処理時間2時
間を推奨下限値として夫々設定することができる。Examples include phosphoric acid 1 and the like. Further, the oxidation treatment performed prior to the nitric acid treatment is performed by heating in an oxidizing atmosphere, such as the atmosphere, and the preferred upper limit of the heating temperature is 700°C. In the case of simple preliminary heat treatment, the nitric acid treatment conditions do not reduce the corrosion resistance improvement effect even if somewhat relaxed, and the recommended lower limit is nitric acid concentration of 2N, geographical temperature of 20''C, treatment time of 2 hours. Can be set respectively.
硝酸処理以外の処理、即ちRa5s、燐酸処理。Treatments other than nitric acid treatment, ie Ra5s, phosphoric acid treatment.
弗酸処理、純水処理の夫々単独1wtいは大気中。1 wt each for hydrofluoric acid treatment and pure water treatment or in the atmosphere.
蒸慨中での加熱酸化、更には該酸化後OR酸処理。Heating oxidation during steaming, and further OR acid treatment after the oxidation.
燐酸処m、弗酸処理、純水処理等は、T ’ @ !
’ ITi尋の耐食性を実質的に向上させる程度迄には
至らなかった。For phosphoric acid treatment, hydrofluoric acid treatment, pure water treatment, etc., please contact T'@!
'It did not reach the level of substantially improving the corrosion resistance of ITi fathom.
以上述べた如く硝酸処理又は硝酸と他の酸との混酸処理
、更には酸化性雰S*下での加熱に引き続く上述の酸処
理を行なうことによって、T1゜zr、’ra醇の耐食
性を有意義に改譬し得るに至った。この様な効果を挙げ
るに至った増肉についての理論的解明を完全に終えた訳
ではないが、iii在迄に判明したところは下記oa、
bであゐ。但し理論的背景の相違があって亀、上述の主
旨に反しない範囲での変更実施及び改善実施は全て本発
明の範囲に含まれる。As mentioned above, by performing nitric acid treatment or mixed acid treatment with nitric acid and other acids, and further by performing the above-mentioned acid treatment following heating in an oxidizing atmosphere S*, the corrosion resistance of T1゜zr,'ra sake can be significantly improved. It has come to be possible to change it to . Although we have not completely elucidated the theoretical explanation of the increase in thickness that led to this effect, what we have found so far is the following oa,
It's b. However, due to differences in theoretical background, all changes and improvements within the scope of the above-mentioned spirit are included within the scope of the present invention.
即ちTi、Zr及びTa中に含まれる轍量の脚素は、夫
々母材金属と結合してTiC,ZrC。That is, the rutted foot elements contained in Ti, Zr, and Ta combine with the base metals to form TiC and ZrC, respectively.
TaC等の炭化物を形成し、非金属介在物として母材中
に析出して匹るが、これら炭化物の自然電位は極めて高
い。従ってこれらの母材に例えばハロゲンイオン含有溶
液を接触させると、C/−イオン等が母材表面に露出し
ている炭化物の周辺に泳動し、当該部分にかけるct−
イオン等の濃度が濃縮された状態となシ、この部分でC
t1!等の発生が起こJ)、Ti、zr、Ta等の表面
に形成されている不働態皮膜が破壊され、破壊部分から
孔食が始まる様である。これらの状況はオージェ(AU
GER)分析や走査型電子顕微鏡像等の観察によって明
らかにされてシ〕、孔食部には各炭化物が粒状となって
存在している。第2,8図はこれらを示す図面代用電子
顕微鏡写真であり、いずれも、孔食部に直径1μm程度
の粒子が認められる。Carbides such as TaC are formed and precipitated in the base material as nonmetallic inclusions, but the natural potential of these carbides is extremely high. Therefore, when these base materials are brought into contact with, for example, a solution containing halogen ions, C/- ions etc. migrate around the carbide exposed on the base material surface, and the ct-
If the concentration of ions etc. is in a concentrated state, C
t1! It appears that the passive film formed on the surface of Ti, Zr, Ta, etc. is destroyed, and pitting corrosion begins from the destroyed portion. These situations are similar to those of Auger (AU).
It has been revealed by GER) analysis and observation of scanning electron microscopy images that various carbides exist in the form of particles in pitting areas. FIGS. 2 and 8 are electron micrographs used as drawings showing these, and in both of them, particles with a diameter of about 1 μm are observed in the pitting areas.
これに対し本発明の上記手段を採用すると、母材表面に
露出している’riC,zrcsTac等の炭化物が硝
酸中に溶出され、溶出した後の凹部を含む全表面に不働
態皮膜が形成される。従って母材表面の電位が均一にな
夛、前述した様なへロゲンイオンの濃縮部がなくなって
孔食の発生因子が激減するものと患われる。On the other hand, when the above means of the present invention is adopted, carbides such as 'riC and zrcsTac exposed on the surface of the base material are eluted into nitric acid, and a passive film is formed on the entire surface including the recesses after being eluted. Ru. Therefore, as the potential on the surface of the base material becomes uniform, the concentration of herogen ions as mentioned above disappears, and the factors that cause pitting corrosion are drastically reduced.
本発明は上述の如く構成されているので、’i’+。Since the present invention is configured as described above, 'i'+.
zr、’ra等で代表される新金属の過酷条件下におけ
ゐ耐食性を実質的に改曽し得るに至〕、上記素材を用い
る化学装置の耐久性が向上し、且つ安全性も高め得るに
至った。It has become possible to substantially improve the corrosion resistance of new metals represented by ZR, 'RA, etc. under harsh conditions, and the durability and safety of chemical equipment using the above materials can be improved. reached.
@1図は電位−電流曲線、@2.II図は図面代用のm
ii鋺写真で、金属組織を表わす亀のである。
出願人 株式会社神戸製鋼所
第1図
電位
Vvs Ag/AgC/
第2図
第3図@1 Figure is the potential-current curve, @2. Figure II is a substitute for a drawing.
ii This is a photo of a turtle showing the metal structure. Applicant: Kobe Steel, Ltd. Figure 1 Potential V vs Ag/AgC/ Figure 2 Figure 3
Claims (1)
耐食性を向上する方法であって、少なくても上記新金属
素材部分の表面を硝酸で地理することを特徴とする化学
装置の耐食性向上方法。 (り特許請求の範囲第1項において、新金属素材部分を
沸騰硝酸中に浸漬する耐食性向上方法。 (3)特許請求の範囲第1又は2項において、新金属素
材部分が、予め酸化膜の形成されたものである耐食性向
上方法。 (4)特許請求の範囲第8項において、新金属素材の酸
化膜は、酸化性ガス算囲気中での加熱地理によって形成
されたものである耐食性向上方法。[Claims] A method for improving the corrosion resistance of a chemical device using new metals such as flITi, Zr, and Ta brocade, characterized in that at least the surface of the new metal material portion is coated with nitric acid. Method for improving corrosion resistance of chemical equipment. (In claim 1, the method for improving corrosion resistance involves immersing a new metal material part in boiling nitric acid. (3) In claim 1 or 2, the new metal material part is coated with an oxide film in advance (4) A method for improving corrosion resistance in which the oxide film of the new metal material is formed by heating in an oxidizing gas atmosphere. .
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP13820181A JPS5839785A (en) | 1981-09-02 | 1981-09-02 | Method for improving corrosion resistance of chemical equipment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP13820181A JPS5839785A (en) | 1981-09-02 | 1981-09-02 | Method for improving corrosion resistance of chemical equipment |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5839785A true JPS5839785A (en) | 1983-03-08 |
Family
ID=15216439
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP13820181A Pending JPS5839785A (en) | 1981-09-02 | 1981-09-02 | Method for improving corrosion resistance of chemical equipment |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5839785A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60200972A (en) * | 1984-03-23 | 1985-10-11 | Hitachi Ltd | Corrosion prevention of zirconium or zirconium alloy |
JP2014205896A (en) * | 2013-04-15 | 2014-10-30 | 新日鐵住金株式会社 | Production method of titanium and corrosion prevention method of titanium |
-
1981
- 1981-09-02 JP JP13820181A patent/JPS5839785A/en active Pending
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60200972A (en) * | 1984-03-23 | 1985-10-11 | Hitachi Ltd | Corrosion prevention of zirconium or zirconium alloy |
EP0158177A2 (en) * | 1984-03-23 | 1985-10-16 | Hitachi, Ltd. | Method of inhibiting corrosion of zirconium or its alloy |
US4610732A (en) * | 1984-03-23 | 1986-09-09 | Hitachi, Ltd. | Method of inhibiting corrosion of zirconium or its alloy |
JPH0138873B2 (en) * | 1984-03-23 | 1989-08-16 | Hitachi Ltd | |
JP2014205896A (en) * | 2013-04-15 | 2014-10-30 | 新日鐵住金株式会社 | Production method of titanium and corrosion prevention method of titanium |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5194138A (en) | Method for creating a corrosion-resistant aluminum surface | |
EP0534120B1 (en) | Chromium-free method and composition to protect aluminium | |
JP6811868B2 (en) | Sealing of anodized aluminum using a low temperature nickel-free process | |
JPS63111186A (en) | Metal etching method | |
CN1295630A (en) | Method for developing enhanced oxide coating on component formed from stainless steel or nickel alloy steel | |
JP7172623B2 (en) | Method for manufacturing stainless steel pipes and welded joints | |
JPS5839785A (en) | Method for improving corrosion resistance of chemical equipment | |
EP0021602B1 (en) | Treatment of tin plate surfaces against sulphide staining | |
US20180291523A1 (en) | Development of a passivated stainless steel surface | |
JPS62188785A (en) | Bright pickling solution for copper and copper alloy | |
JPS59157285A (en) | Pretreatment of martensitic stainless steel | |
JP4508602B2 (en) | Chemical polishing agent for iron-based alloy and surface treatment method for iron-based alloy using the same | |
RU2783432C1 (en) | Method for passivation of the contact surface of equipment made of austenitic nickel-containing steel for protection against aggressive media | |
Zuo et al. | Corrosion Behavior of 3A21 Aluminum Alloy in Water-Ethylene Glycol Coolant under Simulated Engine Working Conditions | |
JP3057033B2 (en) | Stainless steel anticorrosion surface treatment method | |
JP2824174B2 (en) | Titanium material with excellent hydrogen absorption resistance | |
EP0532920B1 (en) | Zirconium and zirconium alloy passivation process | |
CA1088457A (en) | Treating metallic article in molten oxidizing salt before immersion in electrolyte | |
Goodrich et al. | The Dissolution of Steel in the System NH 4 NO 3‐NH 3‐H 2 O | |
JPH03207872A (en) | Surface treatment of steel product by plasma action | |
JPH0225592A (en) | Pore sealing treatment of anodic oxide film | |
JPS63103081A (en) | Surface treatment of sintered parts | |
Mansfeld et al. | Method For Creating Corrosion Resistant Surface On An Aluminum Copper Alloy | |
Shannon et al. | PREPARING ZIRCALOY-2 FOR AUTOCLAVE TESTING--THE PICKLING AND RINSING PROCESS | |
JPS5922797B2 (en) | Anode parts for aluminum anodizing electrolytic treatment |