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
• Beschikbaar in diverse deeltjesgrootteverdelingen

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:

Element	Gewichts %
IJzer (Fe)	Balans
Chroom (Cr)	16-18%
Aluminium (Al)	3-5%
Yttrium (Y)	0.2-0.5%
Koolstof (C)	0,03% max
Silicium (Si)	Max. 1%
Mangaan (Mn)	Max. 1%

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:

Onroerend goed	Waarde
Dichtheid	7.3 g/cm3
Smeltpunt	1400-1450 ¡«C
Thermische geleidbaarheid	29 W/mK
Elektrische resistiviteit	0.6 Ã×´Î.cm
Elasticiteitsmodulus	200 GPa
Poissonconstante	0.27-0.30
Treksterkte	450-650 MPa
Rekgrens	280-480 MPa
Verlenging	15-20%
Oxidatiebestendigheid	Uit voortreffelijk tot 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:

• Gasverstuiving?- High pressure inert gas used to atomize the molten alloy resulting in fine spherical powder ideal for AM.
• Verstuiven van water?- High velocity water jet breaks up the molten stream producing irregular powder particles. Lower cost but higher oxygen pickup.
• Mechanische legering?- Kogelmolen van gemengde elementaire poeders gevolgd door sinteren en secundaire 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:

• additive manufacturing?- Selective laser melting to produce complex parts needing high temperature oxidation resistance.
• Thermische spraycoatings?- Applied via arc spraying to provide protective coatings on components operating at over 1000¡«C.
• Lasvullermetaal?- For joining ferritic stainless steel parts in high temperature applications.
• Ontstekers vaste brandstof?- Powder metallurgy igniter plugs used in industrial furnaces and turbines.
• Bewerking van gesmolten metaal?- 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:

• Grootte deeltjes:?Van 15-45 μm voor AM-methoden, tot 150 μm voor thermische spuitprocessen.
• Morfologie:Sferische, onregelmatige en gemengde vormen. Bolvormig poeder heeft een uitstekende vloeibaarheid.
• Zuiverheid:?From commercial to high purity grades based on application requirements.
• Zuurstofgehalte:Niveaus onder 2000 ppm voor de meeste toepassingen.
• Stroomsnelheid:?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 (Verenigd Koninkrijk)
• Höganäs (Zweden)
• Carpenter Powder Products (USA)
• 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:

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

• Moet worden opgeslagen in verzegelde containers onder inert gas om oxidatie te voorkomen
• Avoid accumulation of fine powder to minimize dust explosion risks
• Use proper PPE, ventilation, grounding and safety practices during handling
• Voorkom contact tussen poeder en onverenigbare materialen
• 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:

• Chemische analyse met OES of XRF om de samenstelling binnen de gespecificeerde limieten te garanderen
• Deeltjesgrootteverdeling volgens ASTM B822-standaard
• Morfologie analyse door middel van 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:

Parameter	OP431	316L
Type	Ferritic	Austenitic
Cr inhoud	16-18%	16-18%
Ni content	–	10-14%
Sterkte bij hoge temperatuur	Hoger	Lager
Weerstand tegen corrosie	Gewoonlijk	Uitmuntend
Kosten	Lager	Hoger
TOEPASSINGEN	Thermal spray, igniters	Automobiel- bouw
Lasbaarheid	Slecht	Uitmuntend

 

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.