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.
Composição química
Haynes® 188 is primarily composed of cobalt with significant additions of chromium, tungsten, nickel, and other elements to enhance its mechanical and thermal properties:
| Elemento | Composição (%) |
|---|---|
| Cobalto (Co) | 39.0 – 41.0 |
| Cromo (Cr) | 20.0 – 24.0 |
| Níquel (Ni) | 20.0 – 24.0 |
| Tungstênio (W) | 13.0 – 15.0 |
| Ferro (Fe) | 3,0 máx. |
| Molibdênio (Mo) | 2,0 – 3,0 |
| Manganês (Mn) | 1,0 máx. |
| Silício (Si) | 00,5 máx. |
| Carbono (C) | 0.05 – 0.15 |
| Boro (B) | 0.01 – 0.05 |
Propriedades mecânicas
Haynes® 188 exhibits exceptional mechanical properties suitable for high-temperature applications:
| Propriedade | Valor |
|---|---|
| Resistência à tração, ksi (MPa) | 130 – 150 (896 – 1034) |
| Força de rendimento (compensação de 0,2%), ksi (MPa) | 65 – 75 (448 – 517) |
| Alongamento (% em 2 polegadas) | 20 – 30 |
| Dureza, Rockwell C (HRC) | 34 – 40 |
Características de desempenho
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.
Aplicações Industriais
Haynes® 188 is widely used in industries where high strength and corrosion resistance at elevated temperatures are critical:
| Setor Industrial | Formulários |
|---|---|
| Aeroespacial | Gas turbine components, including blades, combustors, and transition ducts. |
| Geração de energia | Turbine hot-section components, heat exchangers, and industrial furnace parts. |
| Processamento Químico | High-temperature reactors, catalyst grid supports, and combustion chamber linings. |
Formas e tamanhos
Haynes® 188 is available in various forms and sizes to meet specific application needs:
- Formulários: Sheets, plates, bars, forgings, and wire.
- Tamanhos: Thickness ranging from 0.5 mm to 100 mm for plates, and diameter ranging from 1 mm to 300 mm for round bars.
Padrões de produção
Haynes® 188 conforms to international production standards ensuring quality and reliability:
| Formulário de produto | Formas disponíveis | Tamanhos disponíveis | Padrões de produção |
|---|---|---|---|
| Placas/Folhas | Lençóis, Pratos | Thickness: 0.5 mm – 100 mm | ASTM B435, AMS 5608 |
| Barras/hastes | Barras redondas, barras quadradas | Diameter: 1 mm – 300 mm | ASTM B572, AMS 5608 |
| Forjados | Blocks, Discs, Rings | Size: Customized | ASTM B637, AMS 5772 |
Soldagem e Processamento
Haynes® 188 offers good weldability and processing characteristics:
- Soldagem: Can be welded using methods such as TIG, MIG, and resistance welding. Preheating and post-weld heat treatment may be required to maintain properties.
- Usinabilidade: Generally machined in the solution-annealed condition using carbide tools and appropriate cutting fluids.
Vantagens e desvantagens
| Aspecto | Detalhes |
|---|---|
| Vantagens | Excellent high-temperature strength and oxidation resistance, good fabricability and weldability, and long service life in aggressive environments. |
| Desvantagens | Higher cost compared to standard materials, requires specialized processing and handling due to its high strength and alloying elements. |
Comparação com ligas semelhantes
Haynes® 188 (UNS R30188) is often compared with other cobalt-based superalloys such as Haynes® 25 and Haynes® 230. Here’s a brief comparison:
| Tipo/propriedade da liga | Haynes® 188 | Haynes® 25 | Haynes® 230 |
|---|---|---|---|
| Composição química | 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. |
| Propriedades mecânicas | 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. |
| Formulários | 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.