Rostfritt stål OP431 Pulver

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
• Finns i olika partikelstorleksfördelningar

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:

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:

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:

• Atomisering av gas - Inert gas under högt tryck används för att atomisera den smälta legeringen, vilket resulterar i ett fint sfäriskt pulver som är idealiskt för AM.
• Atomisering av vatten – High velocity water jet breaks up the molten stream producing irregular powder particles. Lower cost but higher oxygen pickup.
• Mekanisk legering - Kulfräsning av blandade elementpulver följt av sintring och sekundär atomisering.

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

Applications of OP431 Powder

Typical applications of OP431 powder include:

• Additiv tillverkning – Selective laser melting to produce complex parts needing high temperature oxidation resistance.
• Beläggningar för termisk sprutning – Applied via arc spraying to provide protective coatings on components operating at over 1000°C.
• Fyllmedel för lödning – For joining ferritic stainless steel parts in high temperature applications.
• Solid Fuel Igniters – Powder metallurgy igniter plugs used in industrial furnaces and turbines.
• Molten Metal Processing – 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:

• Partikelstorlek: Från 15-45 μm för AM-metoder, upp till 150 μm för termiska sprutprocesser.
• Morfologi: Spherical, irregular and blended shapes. Spherical powder has excellent flowability.
• Renhet: Från kommersiella till högrena kvaliteter baserat på applikationskrav.
• Syrehalt: Nivåerna hålls under 2000 ppm för de flesta tillämpningar.
• Flödeshastighet: 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 (Storbritannien)
• Hoganas (Sverige)
• Carpenter Powder Products (USA)
• Praxair Surface Technologies (USA)
• CNPC Powder Group (Kina)

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:

• Kvantitet – $50-100 per kg for bulk orders above 500 kg. Smaller quantities are priced significantly higher.
• Kvalitet - Sfäriskt pulver med hög renhet och kontrollerade egenskaper kräver premiumpriser.
• Leverantör - Stora globala leverantörer erbjuder konkurrenskraftiga priser på grund av högre volymer.
• Geografi - Priserna varierar mellan olika regioner, där Europa och Nordamerika är marknader med högre priser.

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:

• Bör förvaras i slutna behållare under inert gas för att förhindra oxidation
• Undvik ansamling av fint pulver för att minimera risken för dammexplosion
• Använd korrekt personlig skyddsutrustning, ventilation, jordning och säkerhetsrutiner under hanteringen
• Förhindra kontakt mellan pulver och oförenliga material
• 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:

• Kemisk analys med hjälp av OES eller XRF för att säkerställa att sammansättningen ligger inom angivna gränser
• Partikelstorleksfördelning enligt ASTM B822-standarden
• Morfologisk analys genom SEM
• Pulverflödeshastighet mätt enligt ASTM B213-standarden
• Oxygen and nitrogen content testing by inert gas fusion
• Densitet bestämd med heliumpyknometri
• 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:

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.