Aço inoxidável OP431 Powder

Overview of Stainless Steel OP431 Powder

OP431 stainless steel belongs to the ferritic grade steels which contain chromium as the principal alloying element. The addition of aluminum enhances oxidation and corrosion resistance at high temperatures.

Key characteristics of OP431 powder include:

• Excellent oxidation and corrosion resistance up to 1150¡«C
• Good creep resistance and thermal fatigue strength
• Excellent thermo-mechanical stability
• High thermal conductivity and low thermal expansion
• Cost-effective compared to austenitic stainless steels
• Disponíveis em várias distribuições de tamanho de partículas

OP431 powder is ideal for applications requiring oxidation resistance, thermal stability and moderate strength at elevated temperatures.

Chemical Composition of OP431 Powder

OP431 powder has the following nominal composition:

Elemento	% do Peso
Ferro (Fe)	Equilíbrio
Cromo (Cr)	16-18%
Alumínio (Al)	3-5%
Yttrium (Y)	0.2-0.5%
Carbono (C)	0,03% máx
Silício (Si)	1% máximo
Manganês (Mn)	1% máximo

Chromium provides corrosion resistance while aluminum enables excellent oxidation resistance through formation of a protective alumina layer at high temperatures. Yttrium refines the grain size for additional strength.

Properties of OP431 Powder

Key properties of OP431 powder include:

Propriedade	Valor
Densidade	7.3 g/cm3
Ponto de Fusão	1400-1450¡«C
Condutividade térmica	29 W/mK
Resistividade elétrica	0.6 Ã×´Î.cm
Módulo de Young	200 GPa
Razão de Poisson	0.27-0.30
Resistência à Tração	450-650 MPa
Limite de escoamento	280-480 MPa
alongamento	15-20%
Resistência à oxidação	Excelente até 1150¡«C

 

The properties like high temperature strength, oxidation resistance, and thermal stability make OP431 suitable for demanding applications.

Production Method for OP431 Powder

OP431 powder can be produced via:

• Atomização a gás?- High pressure inert gas used to atomize the molten alloy resulting in fine spherical powder ideal for AM.
• Atomização da Água?- High velocity water jet breaks up the molten stream producing irregular powder particles. Lower cost but higher oxygen pickup.
• Ligação Mecânica?- Moagem com esferas de pós elementares misturados seguida de sinterização e atomização secundária.

Gas atomization allows excellent control over particle size distribution, morphology, oxygen pickup and microstructure.

Applications of OP431 Powder

Typical applications of OP431 powder include:

• Manufatura aditiva?- Selective laser melting to produce complex parts needing high temperature oxidation resistance.
• Revestimentos por Projeção Térmica?- Applied via arc spraying to provide protective coatings on components operating at over 1000¡«C.
• Solda de Brasagem?- For joining ferritic stainless steel parts in high temperature applications.
• Partidas de Combustível Sólido?- Powder metallurgy igniter plugs used in industrial furnaces and turbines.
• Processamento de Metais Fundidos?- Powder metallurgy conveyor rolls, tundishes and ladles used in molten metal handling.

Specifications of OP431 Powder

OP431 powder is available under various size ranges, shapes and grades:

• Tamanho da partícula:?De 15 a 45 µm para métodos AM, até 150 µm para processos de projeção térmica.
• Morfologia:?Spherical, irregular and blended shapes. Spherical powder has excellent flowability.
• Pureza:?From commercial to high purity grades based on application requirements.
• Oxigênio:Níveis mantidos abaixo de 2000 ppm para a maioria das aplicações.
• Taxa de fluxo:?Powder can be customized for flow rates above 25 s/50 g.

Global Suppliers of OP431 Powder

Some of the major global suppliers of OP431 powder include:

• Sandvik Osprey (Reino Unido)
• Hoganas (Suécia)
• Carpenter Powder Products (EUA)
• Praxair Surface Technologies (USA)
• CNPC Powder Group (China)

These companies produce various grades of OP431 powder tailored for additive manufacturing, thermal spray, powder metallurgy and other high temperature applications.

Pricing of OP431 Powder

OP431 powder is priced higher than austenitic grades but lower than exotic alloys:

• Quantidade?- $50-100 per kg for bulk orders above 500 kg. Smaller quantities are priced significantly higher.
• Qualidade?- High purity, spherical powder with controlled characteristics demands premium pricing.
• Fornecedor?- Large global suppliers offer competitive pricing owing to higher volumes.
• Geografia?- Prices vary between regions with Europe and North America being higher priced markets.

For critical applications, buyers should focus on quality rather than lowest cost while procuring OP431 powder.

Storage and Handling of OP431 Powder

OP431 powder requires the following storage and handling:

• Deve ser armazenado em recipientes lacrados sob gás inerte para evitar oxidação.
• Avoid accumulation of fine powder to minimize dust explosion risks
• Use proper PPE, ventilation, grounding and safety practices during handling
• Evite contato do pó com materiais incompatíveis
• Follow safety guidelines provided by supplier SDS

Proper protective measures must be taken when handling this reactive alloy powder.

Inspection and Testing of OP431 Powder

Key quality control tests performed on OP431 powder include:

• Análise química usando OES ou XRF para garantir que a composição está dentro dos limites especificados
• Distribuição do tamanho de partículas conforme a norma ASTM B822
• Análise da morfologia por meio de MEV
• Taxa de fluxo de pó medida de acordo com a norma ASTM B213
• Oxygen and nitrogen content testing by inert gas fusion
• Density determined by helium pycnometry
• Microstructure characterization by XRD

Testes minuciosos garantem que o pó atenda às características químicas, físicas e microestruturais necessárias para a aplicação pretendida.

Comparison Between OP431 and 316L Stainless Steel Powders

OP431 and 316L stainless steel powders are compared:

Parâmetro	OP431	316L
Tipo	Ferritic	Austenitic
Teor de Cr	16-18%	16-18%
Ni content	–	10-14%
Resistência a altas temperaturas	Maior	Mais baixo
Resistência à corrosão	Moderado	Excelente
Custo	Mais baixo	Maior
APLICATIVOS	Thermal spray, igniters	Automotivo, construção
Soldabilidade	Pobre	Excelente

 

OP431 offers much better high temperature strength whereas 316L provides excellent fabrication characteristics and corrosion resistance.

OP431 Powder FAQs

Q: How is OP431 powder produced?

A: OP431 powder is commercially produced using gas atomization, water atomization, and mechanical alloying followed by sintering. Gas atomization provides the best control of powder characteristics.

Q: What are the main applications of OP431 powder?

A: Key applications include thermal spray coatings, additive manufacturing, brazing filler, powder metallurgy igniter plugs, and high temperature molten metal handling components where oxidation resistance is needed.

Q: What is the typical OP431 powder size range used in metal AM?

A: For most metal AM processes, the ideal OP431 powder size range is 15-45 microns with spherical morphology and good powder flow characteristics.

Q: Does OP431 powder require any special handling precautions?

A: Yes, it is recommended to handle this reactive powder carefully under inert atmosphere using proper ventilation, grounding, and PPE.

Q: Where can I purchase OP431 powder suitable for thermal spray coatings?

A: For thermal spray applications requiring high temperature oxidation resistance, OP431 powder can be purchased from leading manufacturers including Sandvik Osprey, Hoganas, Praxair Surface Technologies, and CNPC Powder Group.