Haynes® 188 (Alloy 188) UNS R30188 Product Introduction
Haynes® 188, also known as Alloy 188 and designated as UNS R30188, is a cobalt-based superalloy renowned for its excellent high-temperature strength, oxidation resistance, and fabricability. This article provides a comprehensive introduction to Haynes® 188, covering its chemical composition, mechanical properties, performance at different temperatures, industry applications, shapes and sizes, production standards, welding and processing capabilities, advantages and disadvantages, and a comparison with similar alloys.
التركيب الكيميائي
Haynes® 188 is primarily composed of cobalt with significant additions of chromium, tungsten, nickel, and other elements to enhance its mechanical and thermal properties:
| عنصر | تعبير (٪) |
|---|---|
| كوبالت (كو) | 39.0 – 41.0 |
| الكروم (الكروم) | 20.0 – 24.0 |
| النيكل (ني) | 20.0 – 24.0 |
| التنغستن (ث) | 13.0 – 15.0 |
| الحديد (الحديد) | 3.0 كحد أقصى |
| الموليبدينوم (مو) | 2.0 – 3.0 |
| المنغنيز (من) | 1.0 كحد أقصى |
| السيليكون (سي) | 0.5 كحد أقصى |
| الكربون (ج) | 0.05 - 0.15 |
| Boron (B) | 0.01 – 0.05 |
الخواص الميكانيكية
Haynes® 188 exhibits exceptional mechanical properties suitable for high-temperature applications:
| ملكية | قيمة |
|---|---|
| قوة الشد، ksi (MPa) | 130 – 150 (896 – 1034) |
| قوة الخضوع (إزاحة 0.2%)، ksi (MPa) | 65 – 75 (448 – 517) |
| استطالة (٪ في 2 بوصة) | 20 – 30 |
| صلابة، روكويل C (HRC) | 34 – 40 |
خصائص الأداء
Haynes® 188 offers several performance advantages:
- High-Temperature Strength: Maintains excellent mechanical properties at temperatures up to 1093°C (2000°F), making it suitable for gas turbine engine components, such as turbine blades, combustors, and afterburners.
- Oxidation Resistance: Exhibits superior resistance to oxidation and corrosion in high-temperature environments, extending component lifetimes.
- Fabricability: Provides good weldability and formability, allowing for complex shapes and configurations.
تطبيقات الصناعة
Haynes® 188 is widely used in industries where high strength and corrosion resistance at elevated temperatures are critical:
| قطاع الصناعة | التطبيقات |
|---|---|
| الفضاء الجوي | Gas turbine components, including blades, combustors, and transition ducts. |
| توليد الطاقة | Turbine hot-section components, heat exchangers, and industrial furnace parts. |
| المعالجة الكيميائية | High-temperature reactors, catalyst grid supports, and combustion chamber linings. |
الأشكال والأحجام
Haynes® 188 is available in various forms and sizes to meet specific application needs:
- النماذج: Sheets, plates, bars, forgings, and wire.
- الأحجام: Thickness ranging from 0.5 mm to 100 mm for plates, and diameter ranging from 1 mm to 300 mm for round bars.
معايير الإنتاج
Haynes® 188 conforms to international production standards ensuring quality and reliability:
| شكل المنتج | الأشكال المتاحة | الأحجام المتاحة | معايير الإنتاج |
|---|---|---|---|
| لوحات / صفائح | Sheets, Plates | Thickness: 0.5 mm – 100 mm | ASTM B435, AMS 5608 |
| قضبان / قضبان | Round bars, Square bars | Diameter: 1 mm – 300 mm | ASTM B572, AMS 5608 |
| المطروقات | Blocks, Discs, Rings | Size: Customized | ASTM B637, AMS 5772 |
اللحام والمعالجة
Haynes® 188 offers good weldability and processing characteristics:
- اللحام: Can be welded using methods such as TIG, MIG, and resistance welding. Preheating and post-weld heat treatment may be required to maintain properties.
- Machinability: Generally machined in the solution-annealed condition using carbide tools and appropriate cutting fluids.
المميزات والعيوب
| وجه | تفاصيل |
|---|---|
| مزايا | Excellent high-temperature strength and oxidation resistance, good fabricability and weldability, and long service life in aggressive environments. |
| سلبيات | Higher cost compared to standard materials, requires specialized processing and handling due to its high strength and alloying elements. |
Comparison with Similar Alloys
Haynes® 188 (UNS R30188) is often compared with other cobalt-based superalloys such as Haynes® 25 and Haynes® 230. Here’s a brief comparison:
| Alloy Type/Property | Haynes® 188 | Haynes® 25 | Haynes® 230 |
|---|---|---|---|
| التركيب الكيميائي | Cobalt, chromium, nickel, tungsten, molybdenum for high-temperature strength and oxidation resistance. | Cobalt, chromium, nickel, tungsten, molybdenum for high-temperature strength and oxidation resistance. | Cobalt, chromium, nickel, tungsten, molybdenum for high-temperature strength and oxidation resistance. |
| الخواص الميكانيكية | High tensile and yield strength, good ductility and formability. | Similar tensile and yield strength, good resistance to thermal fatigue and oxidation. | Higher tensile and yield strength compared to Haynes® 188, excellent thermal stability and corrosion resistance. |
| التطبيقات | Gas turbine components, aerospace hot-section parts, industrial furnace components. | Aerospace components, gas turbine combustors, industrial furnace parts. | Aerospace and industrial gas turbine components requiring high-temperature strength and corrosion resistance. |
This detailed article introduces Haynes® 188 (Alloy 188, UNS R30188), highlighting its chemical composition, mechanical properties, performance characteristics, industry applications, available forms and sizes, production standards, welding and processing capabilities, as well as advantages, disadvantages, and a comparison with similar alloys. Engineers and professionals seeking a reliable, high-temperature superalloy for demanding applications in aerospace, power generation, and chemical processing will find Haynes® 188 well-suited for use in extreme environments.