Cobalt Alloys HY ST31 / Stellite 31 / UNS R30031 Product Introduction
Cobalt alloys such as HY ST31 (Stellite 31) and UNS R30031 are renowned for their exceptional resistance to wear, corrosion, and high temperatures. This article provides a comprehensive introduction to these alloys, covering their chemical composition, mechanical properties, performance at different temperatures, industry applications, shapes and sizes, production standards, welding and processing capabilities, advantages and disadvantages, and comparisons with similar alloys.
التركيب الكيميائي
HY ST31 (Stellite 31) and UNS R30031 have a complex chemical composition designed to achieve their high-performance properties:
| عنصر | تعبير (٪) |
|---|---|
| كوبالت (كو) | 30.0 – 34.0 |
| الكروم (الكروم) | 27.0 – 31.0 |
| التنغستن (ث) | 12.0 – 15.0 |
| النيكل (ني) | 3.0 - 5.0 |
| الحديد (الحديد) | 3.0 – 4.5 |
| الموليبدينوم (مو) | 2.0 – 3.5 |
| الكربون (ج) | 0.05 – 0.15 |
| المنغنيز (من) | 1.0 كحد أقصى |
| السيليكون (سي) | 1.0 كحد أقصى |
| الفوسفور (ف) | 0.04 max |
| الكبريت (S) | 0.04 max |
الخواص الميكانيكية
HY ST31 (Stellite 31) and UNS R30031 exhibit excellent mechanical properties suitable for high-stress applications:
| ملكية | قيمة |
|---|---|
| قوة الشد، ksi (MPa) | 135 (930) min |
| قوة الخضوع (إزاحة 0.2%)، ksi (MPa) | 105 (725) min |
| استطالة (٪ في 2 بوصة) | 20 دقيقة |
| صلابة، روكويل C (HRC) | 38 – 44 |
خصائص الأداء
These cobalt alloys offer outstanding performance in severe environments:
- ارتداء المقاومة: Exceptional resistance to abrasion, erosion, and metal-to-metal wear, making them ideal for high-stress wear applications.
- المقاومة للتآكل: Excellent resistance to oxidation and corrosion in high-temperature and corrosive environments, including acids and alkalis.
- قوة درجة الحرارة العالية: Maintains strength and hardness at elevated temperatures, up to approximately 1200°F (650°C).
تطبيقات الصناعة
HY ST31 (Stellite 31) and UNS R30031 are utilized across various industries where durability and resistance to wear and corrosion are critical:
| قطاع الصناعة | التطبيقات |
|---|---|
| الفضاء الجوي | Turbine blades, combustion chambers, and high-temperature engine components. |
| النفط والغاز | Valves, pump components, and drilling equipment exposed to abrasive and corrosive fluids. |
| Medical | Surgical instruments, prosthetic devices, and biomedical implants requiring wear and corrosion resistance. |
Shapes and Sizes
These alloys are available in various forms and sizes to suit different applications:
- Forms: Sheets, plates, bars, tubes, and custom shapes.
- Sizes: Thickness ranging from 0.025 inches to 1.000 inches (0.64mm to 25.4mm), diameter ranging from 0.25 inches to 6.0 inches (6.35mm to 152.4mm).
معايير الإنتاج
HY ST31 (Stellite 31) and UNS R30031 conform to industry standards ensuring quality and reliability:
| شكل المنتج | الأشكال المتاحة | الأحجام المتاحة | معايير الإنتاج |
|---|---|---|---|
| Bars/Rods | قضبان مستديرة، قضبان مربعة | القطر: 0.25 بوصة – 6.0 بوصة (6.35 ملم – 152.4 ملم) | ASTM A732, AMS 5759 |
| لوحات / صفائح | لوحات، صفائح | السُمك: 0.025 بوصة – 1.000 بوصة (0.64 مم – 25.4 مم) | ASTM A732, AMS 5537 |
| Wires | Wires | Diameter: 0.010″ – 0.250″ (0.25mm – 6.35mm) | ASTM A580, AMS 5832 |
| أنابيب / أنابيب | Tubes, Pipes | OD: 0.250″ – 6.000″ (6.35mm – 152.4mm) | ASTM A732, AMS 5759 |
Welding and Processing
HY ST31 (Stellite 31) and UNS R30031 offer good weldability and machinability:
- Welding: Can be welded using standard methods such as TIG and MIG welding with appropriate preheating and post-weld heat treatment.
- Processing: Machinable using carbide tools, although care is needed due to their high hardness and toughness.
المميزات والعيوب
| وجه | تفاصيل |
|---|---|
| مزايا | High wear resistance, excellent strength at elevated temperatures, good corrosion resistance, and versatility in various applications. |
| سلبيات | Higher cost compared to conventional materials, requires expertise in handling due to their high strength and hardness. |
Similar Alloys
| Alloy Name | مقارنة |
|---|---|
| Cobalt Alloy 6 | Higher cobalt content, offering superior wear resistance and hardness compared to HY ST31 and UNS R30031. |
Comparison of Similar Alloys
| الخاصية/الميزة | HY ST31 / UNS R30031 | Cobalt Alloy 6 |
|---|---|---|
| محتوى الكوبالت (٪) | 30.0 – 34.0 | 54.0 - 62.0 |
| محتوى الكروم (٪) | 27.0 – 31.0 | 25.0 – 32.0 |
| محتوى التنغستن (٪) | 12.0 – 15.0 | 8.0 - 10.0 |
| صلابة، روكويل C (HRC) | 38 – 44 | 48 - 55 |
| التطبيقات | Aerospace, Oil & Gas, Medical | Industrial tools, wear components |
This detailed article provides a comprehensive introduction to HY ST31 (Stellite 31) and UNS R30031, highlighting their chemical composition, mechanical properties, performance characteristics, industry applications, available forms and sizes, production standards, welding and processing capabilities, as well as advantages, disadvantages, and comparisons with similar alloys. Engineers and professionals seeking durable materials for high-wear and corrosion-resistant applications will find this information valuable for selecting the appropriate alloy to meet their specific needs.