WO2017061215A1 - Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof - Google Patents
Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof Download PDFInfo
- Publication number
- WO2017061215A1 WO2017061215A1 PCT/JP2016/076142 JP2016076142W WO2017061215A1 WO 2017061215 A1 WO2017061215 A1 WO 2017061215A1 JP 2016076142 W JP2016076142 W JP 2016076142W WO 2017061215 A1 WO2017061215 A1 WO 2017061215A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- stainless steel
- steel pipe
- polishing
- corrosion resistance
- oxide film
- Prior art date
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B29/00—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents
- B24B29/02—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces
- B24B29/06—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces for elongated workpieces having uniform cross-section in one main direction
- B24B29/08—Machines or devices for polishing surfaces on work by means of tools made of soft or flexible material with or without the application of solid or liquid polishing agents designed for particular workpieces for elongated workpieces having uniform cross-section in one main direction the cross-section being circular, e.g. tubes, wires, needles
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
Definitions
- the present invention relates to a stainless steel pipe excellent in corrosion resistance and a method for producing the same.
- Stainless steel is widely used in building materials such as roofing materials, wall materials, and building materials because it is excellent in weather resistance, workability, weldability, and the like. Moreover, since the stainless steel pipe is excellent in design, the surface is polished and used for applications such as handrails, fences, and pipe shutters.
- polishing removal is performed to remove wrinkles and the like of the raw pipe before polishing, and then final polishing and gloss polishing are performed.
- rough polishing and finish polishing in this polishing operation dry polishing using a flap wheel, a polishing belt, or the like is performed. Further, after the above process, wet polishing by buffing may be performed to obtain a desired surface.
- stainless steel has excellent weather resistance as a material, but depending on the state of the polished finish, it may not exhibit the weather resistance inherent to the material and may cause significant bruising. This is one of the factors that eliminate the stability (reliability) of weather resistance. For example, it may occur in a short period of about one month after construction on an outdoor handrail.
- the starting point is the oxide film and polishing marks remaining on the polished surface of the stainless steel pipe.
- the remaining oxide film is a film generated due to heat generation during polishing, and a Cr-deficient layer is formed immediately below the oxide film.
- the firing proceeds from the oxide film and the Cr-deficient layer immediately below the oxide film, and the corrosion resistance tends to deteriorate.
- the polishing marks which are ridges carved on the surface of the stainless steel pipe by polishing, the deeper the recesses in the polishing marks, the more likely the oxide film generated by the flap wheel polishing or the like is difficult to be removed by buffing and remain. Since the height becomes higher and the concave portion of the polished eye becomes the starting point of the cracking, the cracking proceeds and the corrosion resistance tends to deteriorate.
- Patent Document 1 proposes a stainless steel tube capable of maintaining glossiness and weather resistance over a long period of time in a surface-polished state that does not generate wrinkles even in an outdoor environment in a short period of time.
- Patent Document 1 is a stainless steel pipe having a surface roughness after final polishing of Ry 0.6 ⁇ m or less and an area ratio of the remaining oxide film of 7.0% or less. That is, by setting the surface roughness after final polishing to Ry 0.6 ⁇ m or less, an attempt is made to reduce the oxide film remaining in the recesses of the polishing eyes. Further, by setting the area ratio of the remaining oxide film to 7.0% or less, it is intended to suppress the progress of cracking and deterioration of corrosion resistance starting from the oxide film and the Cr-deficient layer immediately below the oxide film.
- the area ratio of the remaining oxide film in the weather-resistant product is 3.1 to 6.8%, and the oxide film remains. For this reason, there still remains a problem that the rusting can progress and the corrosion resistance can be deteriorated starting from the remaining oxide film and the Cr-deficient layer directly therebelow.
- Patent Document 1 SUS304 is cited as one of the types of stainless steel pipes having excellent weather resistance.
- SUS304 is spawned at an early stage, and there is a problem that maintenance is required.
- An object of the present invention is to solve the above-described problems and to provide a stainless steel pipe excellent in corrosion resistance that does not start at an early stage even in a waterfront environment affected by sea salt particles, and a method for producing the same. .
- the present inventors examined the stainless steel pipe described in Patent Document 1.
- polishing by a flap wheel is performed.
- the oxide film on the surface of the stainless steel pipe of the example of Patent Document 1 using the polishing method remains 3.1% or more in area ratio.
- the surface of the stainless steel pipe surface is high temperature and the oxide film is generated at the time of flap wheel polishing, which is dry polishing, and surface defects are generated along with the polishing marks that are engraved by the high grinding resistance by dry polishing.
- the surface defect here means that when polishing the steel pipe surface, the polishing material or the abrasive paper continuously contacts the steel pipe surface and is polished, so that the metal on the surface is partially peeled and covers the substrate part.
- the surface defect includes a portion where the metal is turned up like a strip shape or a bamboo leaf shape, and the maximum length from one end portion of the portion adhered to the substrate to the other end portion of the peeling tip is 5 ⁇ m. It is the above defect. Since the surface defect forms a minute gap with the surface base portion of the stainless steel pipe, crevice corrosion is likely to occur, which causes a reduction in the corrosion resistance of the steel pipe.
- the present inventors have found a stainless steel pipe excellent in corrosion resistance and a method for producing the same based on the analysis result.
- the present invention provides the following (1) to (3) stainless steel pipes having excellent corrosion resistance and a method for producing the same.
- the surface of the stainless steel tube has a polished surface, no colored oxide film is present on the surface, and the average number of surface defects including a metal substrate covering of 5 ⁇ m or more on the surface is 0.01 mm.
- the stainless steel pipe of the present invention Since the stainless steel pipe of the present invention has polished eyes on the surface of the stainless steel pipe, it is excellent in design and antiglare properties. In addition, since the colored oxide film does not exist on the surface of the stainless steel pipe, the firing starting from the oxide film and the Cr-deficient layer immediately below the oxide film hardly proceeds, and the corrosion resistance is not easily deteriorated. Furthermore, since the average number of surface defects including the covering of the metal substrate of 5 ⁇ m or more on the surface of the stainless steel pipe is suppressed to 5 or less per 0.01 mm 2 , the stainless steel pipe excellent in corrosion resistance is suppressed in crevice corrosion. It becomes.
- the stainless steel pipe of the present invention has a polished surface on the surface of the stainless steel pipe, no colored oxide film is present on the surface, and the average number of surface defects including a metal substrate covering of 5 ⁇ m or more on the surface Is suppressed to 5 or less per 0.01 mm 2 , and is a stainless steel pipe excellent in corrosion resistance.
- the stainless steel pipe has a surface polished to give the surface unevenness and gloss.
- the stainless steel pipe has a polished eye and becomes a stainless steel pipe excellent in design and antiglare properties. Polishing eyes are ridges carved on the surface of a stainless steel pipe by polishing.
- the surface roughness Ra after polishing of the stainless steel pipe surface in the present invention is preferably 0.1 to 1.0 ⁇ m, and more preferably 0.2 to 0.5 ⁇ m.
- the surface roughness after polishing is measured in accordance with JIS B 0601 and can be measured by, for example, a contact-type surface roughness meter.
- the stainless steel pipe of the present invention is characterized in that a colored oxide film does not exist on the surface.
- the present inventors consider that the reason is that the stainless steel pipe of the present invention is caused by removing the oxide film on the surface by polishing with a solid abrasive. Moreover, the generation of an oxide film is further suppressed by attaching a solid abrasive to the polishing flap wheel.
- the presence of a colored oxide film means that when an arbitrary 10 points on the surface of the stainless steel tube are observed with an optical microscope at a magnification of 400 times, the colored oxide film is 50 ⁇ m square.
- the area ratio is 5% or more.
- the coloration is not limited to a specific color, and any color that can be visually distinguished from the metal base or metallic luster of the stainless steel pipe is acceptable. A typical color for coloring is brown.
- the abrasive or abrasive paper continuously contacts the surface of the stainless steel pipe, and the metal on the surface is partially peeled off and the burrs and coverings covered on the substrate part Some surface defects occur.
- the surface defect causes crevice corrosion because a minute gap is formed between the surface base portion of the stainless steel pipe.
- FIG. 1 is an enlarged photograph of the surface of a stainless steel tube with an optical microscope, (a) a surface with suppressed surface defects and (b) a surface with surface defects.
- FIG. 1 (a) shows the surface of the stainless steel pipe of the present invention, which has polished eyes but suppresses surface defects.
- FIG. 1 (b) shows the surface of the stainless steel tube that has been dry-polished, and the surrounding portions 1 to 9 show surface defects that have been partially peeled off and covered with the base portion.
- the present inventors have analyzed that the reason why the surface defects of the stainless steel pipe surface of the present invention are suppressed after polishing as shown in FIG. 1A is that a solid abrasive is used during polishing.
- the white horizontal line in FIG. 1 shows the convex part formed in the case of grinding
- the surface defect means that the maximum length portion of the defect has a covering of a metal substrate having a size of 5 ⁇ m or more.
- the average number of surface defects measured is In the case of 5 or less, the surface defects in the present invention are suppressed.
- the number of surface defects on the polished stainless steel tube surface is preferably 3 or less, more preferably 2 or less per unit area of 100 ⁇ m ⁇ 100 ⁇ m (0.01 mm 2 ).
- FIG. 2 and 3 are diagrams showing the relationship between surface defects and changes in current density.
- FIG. 2 (a) is an enlarged photograph showing the surface defects of the stainless steel pipe
- FIG. 3 (a) shows the suppression of the surface defects of the stainless steel pipe.
- 2 (b) and FIG. 3 (b) are graphs showing current density changes in the pitting corrosion potential measurement of the stainless steel pipes of FIG. 2 (a) and FIG. 3 (a). is there.
- Method B is a pitting potential measurement method by a kinetic potential method in a 3.5% by mass sodium chloride aqueous solution.
- the pH of the aqueous sodium chloride solution is 7 and the temperature is 30 ° C.
- the potential sweep rate is 20 mV / min.
- the rate of change of current density (maximum current density / minimum current density) is 10 or more in the range from the natural potential to the pitting potential. Less than, more preferably 5 or less.
- C is an element useful for obtaining the strength of the steel, but if included in a large amount, it tends to lower the corrosion resistance. Therefore, 0.02% by mass or less is preferable.
- Si is an element useful as a deoxidizer and a heat source in the steelmaking process, but when it is contained in a large amount, it tends to harden the steel, so 1.00% by mass or less is preferable.
- Mn is an element useful as deoxidation in the steelmaking process.
- Mn tends to form an austenite phase, and is preferably 2.00% by mass or less, and more preferably 1.00% by mass or less.
- Cr is an element useful for ensuring corrosion resistance, but if included in a large amount, it tends to decrease not only the cost but also the workability, so that it is preferably 17.00 to 30.00% by mass. More preferred is 00 to 24.00% by mass.
- Mo is an element useful for improving the corrosion resistance of stainless steel in the presence of Cr. However, if it is contained in a large amount, it tends to decrease not only the cost but also the workability, so that 1.00-2. 50% by mass is preferable, and 1.00 to 1.50% by mass is more preferable.
- Ni is preferable in terms of the effect of suppressing the progress of corrosion and the effect of improving the toughness of ferritic stainless steel pipes, but if it is too much, it will cause generation of austenite phase and high cost, so 0.6 mass% or less Is preferred.
- Ti and Nb preferably contain one or two of these. Ti is preferable in that it has a strong affinity with C and N and suppresses intergranular corrosion of ferritic stainless steel pipes. However, since a large amount of Ti tends to lower the surface quality of steel, it is 0.05 to 0.00%.
- Nb has a strong affinity with C and N, and is preferable in terms of suppressing intergranular corrosion of ferritic stainless steel pipes. However, since a large amount of Nb tends to inhibit toughness, 0.1 to 0.6 mass is preferable. % Is preferred. N, if included in a large amount like C, tends to lower the corrosion resistance, so 0.025% by mass or less is preferable. Al is an element effective for refining and casting as a deoxidizer, but if added in excess, it degrades the surface quality and lowers the weldability and low temperature toughness of the steel, so 0.01 to 0.50 mass. % Is preferred. The balance is preferably Fe and inevitable impurities.
- C is 0.02% by mass or less
- Si is 0.40% by mass or less
- Mn is 0.40% by mass or less
- Cr is 21.00 to 23.00% by mass
- Mo is 1.00 to 1%.
- P is 0.040 mass% or less
- S is 0.030 mass% or less
- Ni is 0.60 mass% or less
- Ti is 0.05 to 0.5 mass%
- Nb is 0.10 to
- the stainless steel pipe of the present invention may be 0.6% by mass, N is 0.025% by mass or less, Al is 0.15% by mass or less, and the balance is Fe.
- the material of the stainless steel pipe of the present invention preferably has a pitting corrosion index (PI) of 20 or more.
- PI is given by the following formula (1).
- PI Cr + 3Mo Formula (1)
- the stainless steel pipe of the present invention having a pitting corrosion index (PI) of 20 or more is excellent in corrosion resistance. For this reason, SUS304 having a pitting resistance index as low as 19 starts early in a waterfront environment affected by sea salt particles, whereas the stainless steel pipe of the present invention can suppress the start.
- the pitting corrosion index (PI) is more preferably 24 or more and further preferably 30 or more from the viewpoint of corrosion resistance.
- the manufacturing method of the stainless steel pipe of the present invention is a manufacturing method having a polishing step of polishing the surface of the stainless steel pipe with a solid abrasive.
- the solid abrasive is not particularly limited as long as it contains a fatty acid and mineral oil.
- the solid abrasive preferably contains an oxide such as SiO 2 , Al 2 O 3 , or CrO 2 .
- the content of oxides such as SiO 2 , Al 2 O 3 and CrO 2 is preferably 50 to 80% by mass, more preferably 55 to 75% by mass, and 60 to 70% by mass. Is particularly preferred.
- fatty acid it is preferable to use stearic acid, myristic acid or the like.
- mineral oil or fat it is preferable to use palmitic acid or the like.
- the surface of the stainless steel pipe is polished with a polishing flap wheel and a solid abrasive is attached to the polishing flap wheel in the polishing step.
- the abrasive or polishing paper continuously contacts the surface of the stainless steel tube, and the metal on the surface is partially peeled off to cover the base portion A surface defect that is a fogging occurs.
- this invention is not restrict
- buffing using a solid abrasive may be performed.
- a polishing apparatus air sander
- Polishing was performed on lines 1 to 4 as follows.
- the polishing conditions are as follows.
- Line 1 is a line in which five flap wheels (# 240, # 240, # 240, # 400, # 600) are lined up so as to polish the circumferential direction of the steel pipe surface (giving circumferential polishing marks). It is.
- Line 2 is a line in which four flap wheels (# 240, # 240, # 240, # 400) are lined up so as to polish the longitudinal direction of the surface of the steel pipe (giving a polishing grain in the longitudinal direction).
- Line 3 is a line in which four flap wheels (# 150, # 150, # 150, # 320) are lined up so as to polish the longitudinal direction of the surface of the steel pipe (giving a polishing grain in the longitudinal direction).
- Line 4 comprises three flap wheels (# 320, # 400, # 600) arranged so as to polish the longitudinal direction of the surface of the steel pipe (giving longitudinal polishing marks) and the circumferential direction of the surface of the steel pipe ( It is a line composed of two cotton buffs (# 400, # 400) arranged so as to give a circumferential polishing line.
- a solid abrasive was applied to the flap wheel.
- no solid abrasive was applied in line 2 and line 3.
- “# 240” and the like indicate the mesh granularity.
- Solid abrasive (Solid abrasive) The solid abrasive had a SiO 2 content of 75 mass%, a fatty acid stearic acid content of 16 mass%, and a mineral oil fat palmitic acid content of 3.8 mass%. .
- Example 1 About the steel type 1, it grind
- Example 2 About the steel type 1, after grinding
- a polishing device air sander
- the stainless steel pipe surface of Example 1 was free from surface defects as shown in FIG.
- the surface of the stainless steel pipe of Comparative Example 1 had at least nine surface defects as shown in FIG. 1B and was not in a state in which the surface defects were suppressed.
- the surface of the stainless steel pipe of Comparative Example 2 had at least 6 surface defects as shown in FIG. 4 and was not in a state in which the surface defects were suppressed.
- Reference Example 1 had no surface defects as shown in FIG.
- Example 1 As shown in Table 1, in Example 1, the area ratio of the oxide film was 1% or less, and in Example 2, the area ratio of the oxide film was 3%, and there was no colored oxide film. On the other hand, in Comparative Examples 1 and 2, the area ratio of the oxide film was 15% and 20%, and the surface of the stainless steel pipe had a colored oxide film. In Reference Example 1, the area ratio of the oxide film was 2%, and there was no colored oxide film.
- FIG. 6 shows a surface photograph after the CCT test of Example 1 and Comparative Example 1.
- Example 1 as shown in FIG. 6 (a), no wrinkles were generated on the surface even after the CCT test, indicating excellent corrosion resistance.
- Comparative Example 1 the surface was wrinkled after the CCT test as shown in FIG. 6B, and the corrosion resistance was poor.
- Reference Example 1 since the corrosion resistance level of the base material itself was low, the corrosion resistance was ⁇ .
- the pitting corrosion resistance index (PI) is preferably 24 or more.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
- ing And Chemical Polishing (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Electroplating Methods And Accessories (AREA)
- Chemical Treatment Of Metals (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
- Laminated Bodies (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Abstract
Description
(1)研磨目をステンレス鋼管の表面に有し、着色を有する酸化皮膜が該表面上に存在せず、前記表面上における5μm以上の金属素地の被さりを含む表面欠陥の平均個数が0.01mm2当たり5個以内に抑制されている、耐食性に優れたステンレス鋼管。 That is, the present invention provides the following (1) to (3) stainless steel pipes having excellent corrosion resistance and a method for producing the same.
(1) The surface of the stainless steel tube has a polished surface, no colored oxide film is present on the surface, and the average number of surface defects including a metal substrate covering of 5 μm or more on the surface is 0.01 mm. Stainless steel pipe with excellent corrosion resistance, limited to 5 per 2 pieces.
本発明のステンレス鋼管は、研磨目をステンレス鋼管の表面に有し、着色を有する酸化皮膜が該表面上に存在せず、該表面上における5μm以上の金属素地の被さりを含む表面欠陥の平均個数が0.01mm2当たり5個以内に抑制されているため、耐食性に優れたステンレス鋼管である。 (Stainless steel pipe)
The stainless steel pipe of the present invention has a polished surface on the surface of the stainless steel pipe, no colored oxide film is present on the surface, and the average number of surface defects including a metal substrate covering of 5 μm or more on the surface Is suppressed to 5 or less per 0.01 mm 2 , and is a stainless steel pipe excellent in corrosion resistance.
PI=Cr+3Mo 式(1) The material of the stainless steel pipe of the present invention preferably has a pitting corrosion index (PI) of 20 or more. PI is given by the following formula (1).
PI = Cr + 3Mo Formula (1)
本発明のステンレス鋼管の製造方法は、ステンレス鋼管の表面を、固形研磨剤で研磨する研磨工程を有する、製造方法である。 (Production method)
The manufacturing method of the stainless steel pipe of the present invention is a manufacturing method having a polishing step of polishing the surface of the stainless steel pipe with a solid abrasive.
鋼種2(SUS304) Cr:18%、Ni:8%、Si:0.6%、Mn:0.8%、残部Fe
寸法:直径34mm×厚み1.5mm×長さ4000mm。 Steel type 1 (SUS445J1) Cr: 22%, Mo: 1.05%, Ti: 0.2%, Nb: 0.2%, Al: 0.09%, balance Fe
Steel type 2 (SUS304) Cr: 18%, Ni: 8%, Si: 0.6%, Mn: 0.8%, balance Fe
Dimensions: Diameter 34 mm x thickness 1.5 mm x length 4000 mm.
ライン2は、4つのフラップホイール(#240、#240、#240、#400)が、鋼管表面の長手方向を研磨(長手方向の研磨目を付与)するように並んだラインである。
ライン3は、4つのフラップホイール(#150、#150、#150、#320)が、鋼管表面の長手方向を研磨(長手方向の研磨目を付与)するように並んだラインである。
ライン4は、鋼管表面の長手方向を研磨(長手方向の研磨目を付与)するように並んだ3つのフラップホイール(#320、#400、#600)、及び鋼管表面の円周方向を研磨(円周方向の研磨目を付与)するように並んだ2つの綿バフ(#400、#400)からなるラインである。
ここで、ライン1及びライン4では固形研磨剤をフラップホイールに塗布した。一方、ライン2及びライン3では固形研磨剤を塗布しなかった。なお、「#240」等はメッシュ粒度を示す。
Here, in
ライン速度:1.8m/min
管の回転数:380rpm
ホイール回転数:1500rpm
ホイール直径:400mm (Polishing conditions)
Line speed: 1.8m / min
Tube rotation speed: 380 rpm
Wheel rotation speed: 1500rpm
Wheel diameter: 400mm
固形研磨剤は、SiO2含有量が75質量%であり、脂肪酸であるステアリン酸の含有量が16質量%であり、鉱物性油脂であるパルチミン酸の含有量が3.8質量%であった。 (Solid abrasive)
The solid abrasive had a SiO 2 content of 75 mass%, a fatty acid stearic acid content of 16 mass%, and a mineral oil fat palmitic acid content of 3.8 mass%. .
鋼種1について、ライン1(固形研磨剤塗布あり)で研磨を行った。 Example 1
About the
鋼種1について、ライン3(固形研磨剤塗布なし)で研磨を行ったのちに、ライン4(固形研磨剤塗布あり)で研磨を行った。その後、不織布(#80)を取り付けた研磨装置(エアーサンダー)を用い、固形研磨剤を塗布せずに、偏心運動と回転運動をあわせた動きにより、ランダムな研磨目を均一につける研磨を手作業で行った。 (Example 2)
About the
鋼種1について、ライン2(固形研磨剤塗布なし)で研磨を行った。 (Comparative Example 1)
About the
鋼種2について、ライン2(固形研磨剤塗布なし)で研磨を行った。 (Comparative Example 2)
About the
鋼種2について、ライン1(固形研磨剤塗布あり)で研磨を行った。 (Reference Example 1)
About the
光学顕微鏡を用いて研磨されたステンレス鋼管表面を200倍に拡大し、100μm×100μm(0.01mm2)の範囲を観察した。5μm以上の金属素地の被さりを有する表面欠陥が5個以内の場合には表面欠陥が抑制された状態として「○」と評価し、5個より多い場合には表面欠陥が抑制された状態として「×」と評価した(表1参照)。 (Surface defect)
The surface of the polished stainless steel tube was magnified 200 times using an optical microscope, and a range of 100 μm × 100 μm (0.01 mm 2 ) was observed. When the number of surface defects having a metal substrate covering of 5 μm or more is 5 or less, it is evaluated as “◯” as a state in which the surface defects are suppressed. X "(refer to Table 1).
ステンレス鋼管の表面を光学顕微鏡で400倍の倍率で観察し、茶褐色のシミ状物質である酸化皮膜が50μm四方において面積比率でどの程度存在しているかを算出した。残存酸化皮膜の面積比率が3%以上5%未満である場合は、着色を有する酸化皮膜が存在しないとして「○」、残存酸化皮膜の面積比率が3%未満であるより好ましい状態の場合は「◎」と評価し、面積比率が5%以上の場合は着色を有する酸化皮膜が存在するとして「×」と評価した(表1参照)。 (Oxide film)
The surface of the stainless steel tube was observed with an optical microscope at a magnification of 400 times, and it was calculated how much the oxide film, which is a brownish brown stain-like substance, was present in an area ratio of 50 μm square. When the area ratio of the remaining oxide film is 3% or more and less than 5%, “O” indicates that there is no colored oxide film, and when the area ratio of the remaining oxide film is less than 3%, “ When the area ratio was 5% or more, it was evaluated as “x” because there was a colored oxide film (see Table 1).
実施例1、2、比較例1、2及び参考例1のステンレス鋼管について、以下の条件で耐食性試験(塩乾湿複合サイクル試験(CCT試験))を行った。
条件:(1)塩水噴霧(35℃、5%NaCl、15分)
(2)乾燥 (60℃、30%RH、60分)
(3)湿潤 (50℃、95%RH、3時間)
上記条件(1)~(3)を1サイクルとして、30サイクル繰り返した。
評価:試験後の発銹面積が、鋼管表面全体の5%以内のときに耐食性が良好として「○」と評価し、5%より大きく15%以下の場合は「△」、15%より大きい場合は耐食性が不良として「×」と評価した(表1参照)。 (Corrosion resistance test)
The stainless steel pipes of Examples 1 and 2, Comparative Examples 1 and 2 and Reference Example 1 were subjected to a corrosion resistance test (salt-dry moisture combined cycle test (CCT test)) under the following conditions.
Conditions: (1) Salt spray (35 ° C., 5% NaCl, 15 minutes)
(2) Drying (60 ° C., 30% RH, 60 minutes)
(3) Wet (50 ° C., 95% RH, 3 hours)
The above conditions (1) to (3) were set as one cycle, and 30 cycles were repeated.
Evaluation: When the area after the test is within 5% of the entire surface of the steel pipe, the corrosion resistance is evaluated as “Good”, and when it is larger than 5% but not larger than 15%, “△” is larger than 15%. Was evaluated as “x” because of its poor corrosion resistance (see Table 1).
A、B・・・電流密度の変化領域
1 to 9: Surface defects A, B: Current density change region
Claims (3)
- 研磨目をステンレス鋼管の表面に有し、
着色を有する酸化皮膜が前記表面上に存在せず、
前記表面上における5μm以上の金属素地の被さりを含む表面欠陥の平均個数が0.01mm2当たり5個以内に抑制されている、耐食性に優れたステンレス鋼管。 Have a polished eye on the surface of the stainless steel tube,
There is no colored oxide film on the surface,
A stainless steel pipe excellent in corrosion resistance, in which the average number of surface defects including a metal substrate covering of 5 μm or more on the surface is suppressed to 5 or less per 0.01 mm 2 . - ステンレス鋼管の表面を、固形研磨剤で研磨する研磨工程を有する、請求項1記載のステンレス鋼管の製造方法。 The method for producing a stainless steel pipe according to claim 1, further comprising a polishing step of polishing the surface of the stainless steel pipe with a solid abrasive.
- 前記研磨工程において、研磨フラップホイールに前記固形研磨剤を付着させて前記ステンレス鋼管の表面を研磨する、請求項2記載の製造方法。
The manufacturing method according to claim 2, wherein in the polishing step, the surface of the stainless steel pipe is polished by attaching the solid abrasive to a polishing flap wheel.
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201680058079.0A CN108136562A (en) | 2015-10-05 | 2016-09-06 | The stainless steel tube and its manufacturing method of excellent corrosion resistance |
MYPI2018000469A MY182694A (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe wth excellent corrosion resistance and manufacturing method thereof |
CA3000608A CA3000608C (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
SG11201802748QA SG11201802748QA (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
US15/765,031 US20180304433A1 (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
KR1020187012900A KR102067916B1 (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method |
ES16853369T ES2927025T3 (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent resistance to corrosion and its manufacturing process |
EP16853369.3A EP3360643B1 (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
PH12018500734A PH12018500734A1 (en) | 2015-10-05 | 2018-04-03 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
HK18110007.0A HK1250687A1 (en) | 2015-10-05 | 2018-08-03 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2015197977A JP6138209B2 (en) | 2015-10-05 | 2015-10-05 | Stainless steel pipe excellent in corrosion resistance and manufacturing method thereof |
JP2015-197977 | 2015-10-05 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2017061215A1 true WO2017061215A1 (en) | 2017-04-13 |
Family
ID=58487533
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2016/076142 WO2017061215A1 (en) | 2015-10-05 | 2016-09-06 | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof |
Country Status (13)
Country | Link |
---|---|
US (1) | US20180304433A1 (en) |
EP (1) | EP3360643B1 (en) |
JP (1) | JP6138209B2 (en) |
KR (1) | KR102067916B1 (en) |
CN (1) | CN108136562A (en) |
CA (1) | CA3000608C (en) |
ES (1) | ES2927025T3 (en) |
HK (1) | HK1250687A1 (en) |
MY (1) | MY182694A (en) |
PH (1) | PH12018500734A1 (en) |
SG (1) | SG11201802748QA (en) |
TW (1) | TWI698517B (en) |
WO (1) | WO2017061215A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113696084B (en) * | 2021-09-08 | 2022-10-14 | 瑞兴金属科技(连云港)有限公司 | Corrosion-resistant polishing treatment process and processing equipment for medical stainless steel pipe |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000328045A (en) * | 1999-05-17 | 2000-11-28 | C Uyemura & Co Ltd | Polisher composition |
JP2003025209A (en) * | 2001-07-23 | 2003-01-29 | Nisshin Steel Co Ltd | Polishing method for stainless steel |
JP2003039309A (en) * | 2001-08-01 | 2003-02-13 | Nisshin Steel Co Ltd | Solid polishing agent for polishing stainless steel |
JP2003056755A (en) * | 2001-08-21 | 2003-02-26 | Nisshin Steel Co Ltd | Stainless steel pipe superior in weather resistance |
JP2004209616A (en) * | 2003-01-08 | 2004-07-29 | Ricoh Co Ltd | Tool and method for polishing |
JP2009050945A (en) * | 2007-08-24 | 2009-03-12 | Nihon Micro Coating Co Ltd | Grinding method of tape-shaped backing material and base backing material for oxide superconductor |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0679611A (en) * | 1992-09-02 | 1994-03-22 | Nisshin Steel Co Ltd | Method for polishing stainless steel pipe |
JPH07132454A (en) * | 1993-11-05 | 1995-05-23 | Nisshin Steel Co Ltd | Stainless steel deformed pipe polishing method |
JP2004330394A (en) * | 2003-05-12 | 2004-11-25 | Nisshin Steel Co Ltd | Method for polishing surface of stainless steel product and stainless steel product |
KR101008468B1 (en) * | 2008-06-11 | 2011-01-14 | 주식회사 포스코 | Method for grinding slab of high Cr ferrite stainless steel |
KR20120074802A (en) * | 2010-12-28 | 2012-07-06 | 주식회사 포스코 | Method for grinding ferritic stainless steel |
EP2692452B1 (en) * | 2011-03-31 | 2016-07-20 | Nisshin Steel Co., Ltd. | Stainless steel sheet and method for manufacturing same |
KR101686721B1 (en) * | 2012-03-08 | 2016-12-14 | 제이에프이 스틸 가부시키가이샤 | Seawater-resistant stainless clad steel |
CN103072067A (en) * | 2013-01-25 | 2013-05-01 | 汪正友 | Polishing wheel type selection and configuration for improving surface polishing quality of stainless steel composite pipe |
AU2014100218A4 (en) * | 2014-03-09 | 2014-04-10 | Termsteel Pty Ltd | Method for improving the corrosion resistance of stainless steel mesh used to protect buildings from concealed termite entry |
-
2015
- 2015-10-05 JP JP2015197977A patent/JP6138209B2/en active Active
-
2016
- 2016-09-06 WO PCT/JP2016/076142 patent/WO2017061215A1/en active Application Filing
- 2016-09-06 SG SG11201802748QA patent/SG11201802748QA/en unknown
- 2016-09-06 MY MYPI2018000469A patent/MY182694A/en unknown
- 2016-09-06 CN CN201680058079.0A patent/CN108136562A/en active Pending
- 2016-09-06 KR KR1020187012900A patent/KR102067916B1/en active IP Right Grant
- 2016-09-06 US US15/765,031 patent/US20180304433A1/en not_active Abandoned
- 2016-09-06 EP EP16853369.3A patent/EP3360643B1/en active Active
- 2016-09-06 ES ES16853369T patent/ES2927025T3/en active Active
- 2016-09-06 CA CA3000608A patent/CA3000608C/en active Active
- 2016-10-03 TW TW105131854A patent/TWI698517B/en active
-
2018
- 2018-04-03 PH PH12018500734A patent/PH12018500734A1/en unknown
- 2018-08-03 HK HK18110007.0A patent/HK1250687A1/en unknown
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000328045A (en) * | 1999-05-17 | 2000-11-28 | C Uyemura & Co Ltd | Polisher composition |
JP2003025209A (en) * | 2001-07-23 | 2003-01-29 | Nisshin Steel Co Ltd | Polishing method for stainless steel |
JP2003039309A (en) * | 2001-08-01 | 2003-02-13 | Nisshin Steel Co Ltd | Solid polishing agent for polishing stainless steel |
JP2003056755A (en) * | 2001-08-21 | 2003-02-26 | Nisshin Steel Co Ltd | Stainless steel pipe superior in weather resistance |
JP2004209616A (en) * | 2003-01-08 | 2004-07-29 | Ricoh Co Ltd | Tool and method for polishing |
JP2009050945A (en) * | 2007-08-24 | 2009-03-12 | Nihon Micro Coating Co Ltd | Grinding method of tape-shaped backing material and base backing material for oxide superconductor |
Also Published As
Publication number | Publication date |
---|---|
CA3000608C (en) | 2020-05-05 |
HK1250687A1 (en) | 2019-01-11 |
KR20180066158A (en) | 2018-06-18 |
US20180304433A1 (en) | 2018-10-25 |
EP3360643A1 (en) | 2018-08-15 |
PH12018500734A1 (en) | 2018-10-15 |
JP2017071004A (en) | 2017-04-13 |
MY182694A (en) | 2021-02-01 |
ES2927025T3 (en) | 2022-11-02 |
EP3360643A4 (en) | 2018-10-31 |
TWI698517B (en) | 2020-07-11 |
KR102067916B1 (en) | 2020-01-17 |
CA3000608A1 (en) | 2017-04-13 |
SG11201802748QA (en) | 2018-05-30 |
EP3360643B1 (en) | 2022-08-10 |
CN108136562A (en) | 2018-06-08 |
JP6138209B2 (en) | 2017-05-31 |
TW201726882A (en) | 2017-08-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP6685160B2 (en) | Stainless steel plate with excellent corrosion resistance | |
US9370810B2 (en) | Stainless steel plate | |
KR20170121276A (en) | Ferritic stainless steel sheet, cover member and method for manufacturing ferritic stainless steel sheet | |
WO2017061215A1 (en) | Stainless steel pipe with excellent corrosion resistance and manufacturing method thereof | |
JP6685161B2 (en) | Stainless steel processed products with excellent corrosion resistance | |
JP6584900B2 (en) | Stainless steel pipe excellent in corrosion resistance and manufacturing method thereof | |
JP6108497B1 (en) | Stainless steel pipe with excellent corrosion resistance | |
JP6833335B2 (en) | Stainless steel sheet with excellent corrosion resistance and its manufacturing method | |
JP6778499B2 (en) | Stainless steel sheet with excellent corrosion resistance and its manufacturing method | |
JP6722489B2 (en) | Stainless steel processed product excellent in corrosion resistance and method for manufacturing the same | |
JP6778500B2 (en) | Processed stainless steel products with excellent corrosion resistance and their manufacturing methods | |
CN113340903B (en) | Rapid detection method for rolled steel plate layering | |
JP5974678B2 (en) | Steel member and method for manufacturing steel member | |
JP7414615B2 (en) | Austenitic stainless steel sheet for building materials and its manufacturing method | |
WO2022163160A1 (en) | Stainless steel sheet and method for producing same | |
JP2018095947A (en) | Production method of metal component | |
JP2014162986A (en) | METHOD FOR PRODUCING HIGH Si COLD ROLLED STEEL SHEET | |
JP2005146317A (en) | Hot-rolled steel plate superior in chemical conversion treatability, and manufacturing method therefor | |
JPH09137256A (en) | Grinding-finished stainless steel excellent in rust resistance and its production |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 16853369 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 3000608 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 15765031 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 12018500734 Country of ref document: PH |
|
WWE | Wipo information: entry into national phase |
Ref document number: 11201802748Q Country of ref document: SG |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20187012900 Country of ref document: KR Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2016853369 Country of ref document: EP |