Stainless Steel 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
• Disponible en varias distribuciones de tamaño de partícula

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	Porcentaje de peso
Hierro (Fe)	Equilibrio
Cromo (Cr)	16-18%
Aluminio (Al)	3-5%
Yttrium (Y)	0.2-0.5%
Carbono (C)	0,03% máx
Silicio (Si)	1 % máximo
Manganeso (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:

Propiedad	Valor
Densidad	7.3 g/cm3
Punto de Fusión	1400-1450¡«C
Conductividad térmica	29 W/mK
Resistividad eléctrica	0.6 Ã×´Î.cm
Módulo de Young	200 GPa
Coeficiente de Poisson	0.27-0.30
Resistencia a la tensión	450-650 MPa
Resistencia elástica	280-480 MPa
Elongación	15-20%
Resistencia a la oxidación	Excelente hasta 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:

• Atomización de gas?- High pressure inert gas used to atomize the molten alloy resulting in fine spherical powder ideal for AM.
• Atomización de agua?- High velocity water jet breaks up the molten stream producing irregular powder particles. Lower cost but higher oxygen pickup.
• Aleación Mecánica?- Molienda de bolas de polvos elementales mezclados seguido de sinterización y atomización secundaria.

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

Applications of OP431 Powder

Typical applications of OP431 powder include:

• fabricación aditiva?- Selective laser melting to produce complex parts needing high temperature oxidation resistance.
• Recubrimientos por proyección térmica?- Applied via arc spraying to provide protective coatings on components operating at over 1000¡«C.
• Relleno de soldadura fuerte?- For joining ferritic stainless steel parts in high temperature applications.
• Encendedores de combustible sólido?- Powder metallurgy igniter plugs used in industrial furnaces and turbines.
• Procesamiento de metal fundido?- 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:

• Tamaño de las partículas:?De 15 a 45 µm para métodos AM, hasta 150 µm para procesos de pulverización térmica.
• Morfología:?Spherical, irregular and blended shapes. Spherical powder has excellent flowability.
• Pureza:?From commercial to high purity grades based on application requirements.
• Contenido de Oxígeno:Niveles mantenidos por debajo de 2000 ppm para la mayoría de las aplicaciones.
• Caudal:?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 (RU)
• Höganäs (Suecia)
• Carpenter Powder Products (EE.UU.)
• Praxair Surface Technologies (USA)
• Grupo de Polvos CNPC (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:

• Cantidad?- $50-100 per kg for bulk orders above 500 kg. Smaller quantities are priced significantly higher.
• Calidad?- High purity, spherical powder with controlled characteristics demands premium pricing.
• Proveedor?- Large global suppliers offer competitive pricing owing to higher volumes.
• Geografía?- 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:

• Debe almacenarse en recipientes sellados bajo gas inerte para evitar la oxidación.
• Avoid accumulation of fine powder to minimize dust explosion risks
• Utilizar EPI, ventilación, conexión a tierra y prácticas de seguridad adecuadas durante la manipulación
• Evitar el contacto entre el polvo y materiales incompatibles
• 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:

• Análisis químico mediante OES o XRF para garantizar que la composición se encuentra dentro de los límites especificados
• Distribución de tamaño de partícula conforme a la norma ASTM B822
• Análisis de morfología por SEM
• Powder flow rate measured as per ASTM B213 standard
• Oxygen and nitrogen content testing by inert gas fusion
• Density determined by helium pycnometry
• Microstructure characterization by XRD

Thorough testing ensures the powder meets the required chemical, physical and microstructural characteristics for the intended application.

Comparison Between OP431 and 316L Stainless Steel Powders

OP431 and 316L stainless steel powders are compared:

Parámetro	OP431	316L
Tipo	Ferritic	Austenitic
Contenido de Cr	16-18%	16-18%
Ni content	–	10-14%
Resistencia a altas temperaturas	Alto	Inferior
Resistencia a la corrosión	Moderado	Excelente
Coste	Inferior	Alto
SOLICITUDES	Thermal spray, igniters	Automoción, construcción
Soldabilidad	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.