アイシ 2507 Super-Duplex Stainless Steel: プロパティ, 製造 & Applications Guide

アイシ 2507 super-duplex stainless steel is the gold standard for extreme corrosion resistance and high strength. そのユニーク2507 ferrite-austenite balance 50-50 microstructure and ultra-high2507 PREN ≥ 40 make it ideal for the harshest environments—from deep-sea oil rigs to chemical processing plants. このガイドは、重要な仕様を分類します, パフォーマンス, and real-world uses to help you select it with confidence.

1. マテリアルの概要 & 重要な仕様

Understanding 2507’s composition and standards is critical to unlocking its full potential. 以下は、その重要な特性の明確な内訳です.

化学組成 & 基準

The2507 super-duplex composition is engineered for strength and corrosion resistance: 24–26% chromium, 6–8% nickel, 3–5% molybdenum, and 0.24–0.32% nitrogen. These elements create its balanced microstructure and high PREN. It adheres to global standards:

• 2507 UNS S32750 (統一番号システム)
• 2507 で 1.4410 同等 (マッチングパフォーマンスの欧州標準)
• 2507 ASTM A240 / 2507 ASME SA-240 (プレート用, シート, とストリップ)

物理的な & 機械的特性

2507 delivers exceptional strength—far higher than standard duplex or austenitic alloys. 主要なメトリックは、以下の表に編成されています:

A Norwegian offshore company uses2507 ASTM A240 plates for subsea manifolds—they rely on the 550 MPa yield strength to handle 400 bar deep-sea pressure and corrosive seawater.

2. 耐食性 & 環境パフォーマンス

2507’s biggest advantage is its industry-leading corrosion resistance. Its2507 PREN 41–45 (ピッティング抵抗相当数) is far higher than 2205’s PREN of 35–40, making it nearly immune to pitting, crevice corrosion, and stress cracking in harsh fluids.

主要な腐食耐性特性

• ピッティング & Crevice Corrosion: It has unmatched 2507 pitting corrosion resistance and a high 2507 crevice corrosion threshold—even in tight gaps (例えば。, heat exchanger gaskets) exposed to 60 °C seawater.
• Stress Corrosion Cracking: It offers 2507 chloride stress corrosion cracking immunity—critical for desalination plants and offshore pipelines where chloride levels exceed 10,000 ppm.
• Sour Service: It meets 2507 sour service NACE MR0175 / ISO 15156 基準, resisting 2507 sulfide stress cracking in oil wells with high hydrogen sulfide (H₂S) levels.
• 耐薬品性: It handles 2507 sulfuric acid resistance (resists 30% sulfuric acid up to 50 °C) and has higher 2507 hydrochloric acid limits than 2205 (tolerates dilute HCl up to 30 °C).

2507 vs 2205 腐食の比較: A Saudi desalination plant tested both alloys—2205 tubes showed pitting after 5 年, その間2507 海水腐食率 (≤0.005 mm/year) kept 2507 tubes operational for 15+ 年.

3. 高温 & Low-Temperature Properties

2507 performs well across a wide temperature range, though it’s optimized for moderate heat and cold environments.

High-Temperature Traits

• 強さ & 酸化: It maintains 2507 high-temperature strength まで 300 °C, と 2507 酸化抵抗 300 °C (suitable for warm chemical processes like acid evaporation). The 2507 continuous service temperature は 300 °C—beyond this, avoid prolonged exposure to prevent sigma phase formation.
• クリープ抵抗: 2507 クリープ破裂データ shows it can last 10,000+ での時間 250 °C under 150 MPa stress, making it ideal for high-pressure heat exchanger tubes.

Low-Temperature Traits

• Toughness: It has excellent 2507 low-temperature toughness, と 2507 impact energy at -50 °C of ≥45 J (no brittle fracture). Its 2507 cryogenic ductility also makes it suitable for Arctic offshore projects (例えば。, subsea pipelines in -40 °C conditions).

ケーススタディ: 米国. geothermal plant used2507 熱交換器チューブ (で動作します 280 °C). 後 8 年, no corrosion or creep deformation occurred—unlike the previous 2205 tubes that failed every 3 年.

4. 熱処理 & Microstructure Balance

Proper heat treatment is critical to maintaining 2507’s 50-50 ferrite-austenite balance and avoiding harmful phases like sigma, chi, or alpha-prime.

必須の熱処理プロセス

• ソリューションアニーリング: Heat to 1025–1125 °C, 30〜60分間保持します, then perform a 2507 rapid water quench (critical to prevent phase formation). This step restores the balanced microstructure and dissolves unwanted carbides.
• ホットワーキング: 使用 1150–1000 °C as the 2507 ホット作業範囲 for forging or rolling. This keeps the material ductile and preserves the ferrite-austenite balance.
• 残留応力緩和: Heat to 400–450 °C to reduce stresses from welding or forming. Avoid 475 °C (the 2507 embrittlement at 475 °C 温度) to prevent alpha-prime embrittlement.

微細構造制御

• Ferrite Content: Maintain 2507 ferrite content 35–55 % (tested via magnetic methods) to ensure strength and corrosion resistance.
• Phase Prevention: Avoid heating to 500–800 °C for long periods—2507 sigma phase formation kinetics そして 2507 chi phase precipitation accelerate in this range, making the material brittle.

5. 溶接, 製造 & 機械加工ガイドライン

溶接 2507 requires precise heat control to preserve its microstructure, but it’s workable with the right techniques and consumables.

溶接のヒント

• 消耗品: 使用 2507 welding consumables 2509 / ER2594 (TIG/ME溶接用)—these match 2507’s composition and maintain the ferrite-austenite balance in the weld.
• Heat Input & Interpass Temperature: Strictly control 2507 heat input 0.5–1.5 kJ/mm (lower than 2205’s 0.5–2.5 kJ/mm) and keep 2507 interpass temperature 100 °C max (prevents sigma phase).
• Root Gas Purge: 使用 2507 root gas purge 99.99 % N₂ + 5 % H₂ to ensure full austenite formation in the weld root. 溶接後, perform 2507 post-weld cleaning passivation (pickling with nitric acid) to remove scale and restore corrosion resistance.

機械加工 & 形にする

• 速度 & フィード: 2507 機械加工速度とフィード should be 15–20% lower than 2205. 使用 2507 コーティングされた炭化物を備えたツール寿命 (TiAlN or diamond coatings work best—they resist wear from the alloy’s high strength).
• 形成性: 2507 formability limits are moderate—cold bending is possible for thin sections, but avoid excessive strain (anneal after heavy forming to restore toughness). 使用 2507 歪み制御技術 (例えば。, 溶接中のクランプ, ゆっくりと冷却) to keep parts true to size.

6. 製品フォーム, サイズ & サプライチェーン

2507 is available in a wide range of forms to fit nearly any high-corrosion, high-strength project.

一般的な製品フォーム

• プレート & シート: 2507 super-duplex plate thickness chart ranges from 3 mm to 200 mm; 2507 sheet gauge sizes (16 ゲージに 1/2 インチ) are ideal for chemical vessel liners.
• パイプ & チューブ: 2507 seamless pipe ASTM A790 (for high-pressure offshore flowlines) そして 2507 welded pipe ASTM A928 (for low-pressure desalination lines).
• バー & フィッティング: 2507 ラウンドバーストック (10 mm to 300 mm直径), 2507 角度の鉄のサイズ (20×20 mm〜100×100 mm), そして 2507 ねじ付きロッドグレード (学年 1 for general use, 学年 2 for high-stress applications).
• 専門フォーム: 2507 コイルスリット幅 (10 mm to 1250 mm), 2507 中空のバーサプライヤー (軽量部品用), 2507 カスタムフォーミング (例えば。, バルブボディ), そして 2507 clad plate suppliers (for cost-effective large structures like FGD towers).

サプライチェーンのヒント

Work with global suppliers who stock2507 seamless pipe ASTM A790 and hold NACE MR0175 certification—these ensure compliance for sour service. For urgent offshore projects, prioritize suppliers with local inventory of common sizes to reduce lead times.

7. 業界アプリケーション & ケーススタディ

2507’s unbeatable strength and corrosion resistance make it a top choice for industries facing extreme conditions. Here are key use cases:

• 沖合 & 海兵隊: 2507 offshore flowlines, 2507 subsea pipelines, そして 2507 chemical injection lines (resist seawater, H₂S, and high pressure).
• Water Treatment: 2507 desalination high-pressure piping (ハンドル 80+ bar pressure and high chlorides).
• 力 & 産業: 2507 FGD absorber towers (remove sulfur from power plant exhausts) そして 2507 熱交換器チューブ (for acid and geothermal applications).
• Pulp & 紙: 2507 pulp & paper digesters (resist chlorine-based bleaches and high temperatures).

本当の例: A Brazilian oil company replaced 2205 と 2507 for subsea wellheads—2507 sulfide stress cracking resistance eliminated wellhead failures, メンテナンスコストを削減します 90% and extending service life from 7 に 20 年.

Yigu Technologyの視点

Yiguテクノロジーで, お勧めします 2507 for clients needing extreme corrosion resistance + 高強度. ソース2507 ASTM A240 プレートと2507 seamless pipe ASTM A790 認定工場から, ensuring PREN 41–45 and ferrite content 35–55%. For offshore/sour service clients, we provide NACE MR0175 testing and welding support (使用2509/ER2594 consumables). その間 2507 それ以上の費用がかかります 2205, its 2x longer lifespan and lower maintenance make it cost-effective for the harshest projects.

よくある質問

1. When should I choose 2507 以上 2205?
   選ぶ 2507 if your project involves high chlorides (>10,000 ppm), sour service (H₂S), or high pressure (>300 bar). Its PREN 41–45 そして sulfide stress cracking resistance outperform 2205. 使用 2205 for milder conditions (例えば。, low-pressure seawater) to save cost.
2. できる 2507 be used at temperatures above 300 °C?
   Avoid prolonged use above 300 °C (その continuous service temperature). At 300–500 °C, 2507 シグマ相形成 そして alpha-prime embrittlement occur, reducing toughness. のために 300 °C+ applications, choose 347H (high-temperature strength) or 904L (耐食性).
3. What’s critical for welding 2507?
   Three key steps: 使用 2507 welding consumables 2509/ER2594, control heat input 0.5–1.5 kJ/mm そして interpass temperature 100 °C max, and purge the root with 99.99 % N₂ + 5 % H₂. Post-weld passivation is also required to restore corrosion resistance.