01
Alloy 20 Hot-Finished Round Bar
Rounds reduced hot and descaled, at the diameter the drawing names.
Request Availability →Alloy 20 Round Bar
Niobium-stabilised nickel-iron-chromium round bar with 3-4% copper for sulfuric acid duty and acid plant machining.
Copper at 3.0–4.0%
Copper holds the passive film of this Alloy 20 round bar alive under reducing conditions, which is what carries it through sulfuric acid.
Niobium Tied to Carbon
Moreover, niobium plus tantalum at eight times carbon stabilises this Alloy 20 round bar, so a weld zone needs no post-weld anneal.
Nickel Above a Third
Furthermore, nickel at 32.0–38.0% puts chloride stress corrosion cracking out of reach for this round bar.
PRODUCT OVERVIEW
About Alloy 20 Round Bar
Alloy 20 round bar comes out of UNS N08020, the niobium-stabilised nickel-iron-chromium grade built around its copper content. Copper between 3.0% and 4.0% and nickel between 32.0% and 38.0% carry this Alloy 20 round bar through acid duty.
B473 divides round bar of this grade by finishing route, so hot finished stock begins at 6.35 mm while cold finished stock begins above 12.7 mm. We supply this round bar to ASTM B473 and ASME SB473 in hot-finished, annealed and cold-finished states, with the ASTM B462 forging route above the bar ceiling and ASTM B472 behind the billets. The heat number, the anneal and quench route we ran and the EN 10204 3.1 report travel with every round bar consignment.
Meanwhile, the niobium addition is what lets a fabricated vessel of this round bar go into service without a solution treatment after welding. The full chemistry window and the physical data behind this round bar sit on our Alloy 20 material page, should you want to cross-reference them.
PRODUCT FEATURES
Key Features of Alloy 20 Round Bar
Alloy 20 round bar comes out of UNS N08020, the niobium-stabilised nickel-iron-chromium grade whose copper content carries it through sulfuric acid. We supply ASTM B473 round bar in pickled, peeled, ground and cold-drawn conditions, cut to length for acid plant, pickling house liquor and tankhouse duty. Every Alloy 20 round bar consignment travels with heat-number traceability, EN 10204 3.1 mill test reports and full export documentation.
Alloy 20
Copper at the Signature Level
For example, 3.0–4.0% copper in this round bar keeps the passive film alive where a plain austenitic grade loses it.
01
Wide Acid Concentration Span
Specifically, the copper addition lets this round bar serve across a broad sulfuric acid range rather than only at one end.
02
Niobium Stabilisation
Moreover, niobium plus tantalum at eight times carbon keeps the weld zone of this round bar stable without a furnace pass.
03
Chloride Cracking Out of Reach
Therefore, nickel above a third of the analysis gives this round bar immunity to chloride stress corrosion cracking.
04
Cold Work Sets the Strength
In addition, nothing in this round bar responds to aging, so drawing is the only route above the annealed floor.
05
No Hardness Figure Applies
Besides, B473 carries no hardness column, so this round bar clears on chemistry and tensile results alone.
06
Sour Service Listed
Consequently, NACE MR0175 covers this round bar at the condition that document names, and we document that condition per heat.
07
Essentially Non-Magnetic
Finally, the austenitic matrix keeps this round bar non-magnetic for instrument and seal work.
08
WHY CHOOSE US
Why Choose Alloy 20
On an Alloy 20 round bar order the delivery surface decides more than the diameter does. Besides, we settle the anneal, the descaled skin and the certificate before we price this Alloy 20 round bar.
01
Duty Read Before Pricing
We record the acid, its concentration and its temperature for your round bar before proposing a delivery state.
02
Certificates Tied to the Heat
Specifically, each round bar consignment carries EN 10204 3.1 papers, heat numbers and dimensional records.
03
One Route for Welders and Machinists
In addition, this round bar flows through one process whether your shop welds it into a vessel or turns it on a lathe.
04
Terms Stated in Writing
Quotations for this round bar name the acid, the section, the finish and the document set rather than leaving them open.
MANUFACTURING PROCESS
Reliable Production For Critical Applications
Producing Alloy 20 round bar runs from charge balancing through to the final pack. We log each stage behind this Alloy 20 round bar against its own heat number.
01
Charge Weighing
We charge nickel, chromium, copper and molybdenum to the B473 window before we melt this round bar.
02
Melting and Refining
First, the charge for this round bar melts and refines under AOD practice that brings carbon down to the ceiling.
03
Niobium Addition
Next, we add niobium so that this round bar carries eight times the carbon content in the finished analysis.
04
Hot Reduction
Then, forging and rolling reduce the ingot to this round bar section between 1230 °C and 925 °C.
05
Stabilising Anneal
After that, we hold this round bar between 927 °C and 1010 °C so the niobium carbide goes back into solution.
06
Water Quenching
We then drop this round bar into the tank, because a slow pass through 600–900 °C would precipitate carbide and sigma.
07
Pickling and Finishing
Subsequently, pickling, turning or grinding brings this round bar to the ordered size and surface.
08
Testing and Release
Finally, we clear this round bar for dispatch once chemistry, tensile and dimensional checks come back.
Manufacturing Facility
MANUFACTURING CAPABILITY
Advanced Production For Nickel Alloy Products
One schedule carries both stock lengths and bespoke heats of Alloy 20 round bar. Besides, we quote this Alloy 20 round bar through our bar and rod program.
20,000+ m²
Factory Area
Hot working, annealing, quenching and finishing lines behind the round bar share this site.
50+
Production Machines
Units for hot working, annealing, quenching and grinding of this round bar.
600 Tons
Monthly Capacity
Round bar tonnage across stock lots and bespoke heats.
30+
Technical Engineers
Metallurgists who write the anneal and quench plan that this round bar follows.
30+ Countries
Export Reach
In addition, sealed export packing sends this round bar to buyers on five continents.
QUALITY ASSURANCE
Strict Quality Control From Production To Delivery
Nothing leaves until the heat behind your Alloy 20 round bar clears our ISO 9001 route. In addition, the checks on this Alloy 20 round bar follow the requirements the order names.
01
Heat Identification
We match the grade and heat number on this round bar to your purchase order before anything leaves the yard.
02
Chemistry Verification
Specifically, copper, nickel and niobium in this round bar go against the B473 table for your lot.
03
Tensile Verification
In addition, every heat of this round bar carries reported tensile, yield and reduction-of-area values measured against the B473 floor.
04
Quench Record Referenced
The cooling record behind this round bar travels with its EN 10204 3.1 papers.
PRODUCT FORMS
Available Product Forms
The list below covers the variants we quote for Alloy 20 round bar from your drawing rather than a stock list. In addition, this list covers the deliveries ordered most often for this Alloy 20 round bar.
02
Alloy 20 Cold-Finished Round Bar
Drawn rounds above the half-inch line that B473 sets for this route.
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03
Alloy 20 Peeled Round Bar
Heavy rounds given a turned skin so the surface arrives ready for machining.
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04
Alloy 20 Ground Round Bar
Rounds taken to a close diameter band instead of a turned skin.
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05
Alloy 20 Custom Round Bar
Rounds made to your drawing for diameter, length and delivery state.
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APPLICATIONS
Engineered For Demanding Industries
Alloy 20 round bar suits plant where sulfuric acid sits in the process rather than visiting it. In addition, the list below sets out where this Alloy 20 round bar serves.
Discuss Your Application →
01
Alloy 20 Acid Storage Tank Agitators
Shaft stock for tanks where the liquor blends before it reaches the process.
02
Alloy 20 Sulfuric Acid Cooler Plugs
Plugs and ferrules machined for coolers that take hot acid down to storage temperature.
03
Alloy 20 Pickle Liquor Transfer Pumps
Shafting for pumps that move spent liquor out of a pickling house.
04
Alloy 20 Titanium Dioxide Digester Parts
Machined parts for sulfate-route digesters that run on dilute acid and metal sulfates.
05
Alloy 20 Electrowinning Cell Hardware
Cell pins and busbar studs for tankhouses whose electrolyte stays acidic.
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Alloy 20 Acid Dosing Skid Internals
Metering pump parts for skids that inject acid into a flowing process stream.
07
Alloy 20 Acid Mist Duct Brackets
Bracket and stud stock for ducting that carries acid mist away from a reaction train.
08
Alloy 20 Leach Vessel Fittings
Machined fittings for vessels that leach heavy minerals with hot acid.
TECHNICAL INFORMATION
Technical Specifications
Detailed technical information including chemical composition, mechanical properties, standards and available dimensions.
Chemical Composition
ASTM B473 prints one chemistry window for this round bar, holding nickel between 32.0% and 38.0% and copper between 3.0% and 4.0%. Moreover, niobium plus tantalum in this round bar has to reach eight times the carbon content.
Meanwhile, the full composition table on the Alloy 20 material page carries every limit behind this round bar.
Mechanical Properties
The floors in the table below come from the B473 bar table for UNS N08020. Therefore, the ordered condition and the ruling section settle final acceptance of Alloy 20 round bar.
| Condition | Tensile Strength, min. | Yield Strength (0.2%), min. | Elongation, min. | Reduction of Area, min. |
|---|---|---|---|---|
| Stabilised Annealed — UNS N08020 | ≥551 MPa (80 ksi) | ≥241 MPa (35 ksi) | 30% | 50% |
| Strain Hardened, up to 2 in (50.8 mm) | ≥620 MPa (90 ksi) | ≥415 MPa (60 ksi) | 15% | 40% |
- ASTM B473 prints four columns and no hardness column against UNS N08020, so release rests on chemistry and tensile results rather than on an indenter reading. The 217 HB and 95 HRB figures that circulate for this grade belong to ASTM B463, which covers plate, sheet and strip, and they do not apply to bar. Consequently, we quote the annealed and strain-hardened results and leave hardness out of the acceptance sheet.
Physical Properties
Published design data puts the density of this round bar near 8.08 g/cm³ and its melting range between 1385 °C and 1443 °C. In addition, a modulus close to 193 GPa and a relative permeability near 1.004 leave this round bar non-magnetic in service.
Therefore, the physical properties table on the Alloy 20 material page holds the conductivity, the resistivity and the expansion figures for this round bar.
Heat Treatment
The water quench is the step that defines this Alloy 20 round bar, because the section has to leave the stabilising anneal fast enough to keep carbide and sigma phases out of the grain boundaries. Moreover, the forging band finishes above 925 °C for a different reason: this grade risks incipient melting near 1200 °C.
| Condition | Typical Treatment |
|---|---|
| Stabilised Annealed | Held between 927 °C and 1010 °C, then water quenched, so the niobium carbide returns to solution |
| Hot-Worked | Forged between 1150 °C and 1230 °C, finishing above 925 °C because the section risks incipient melting near 1200 °C |
| Slow-Cool Caution | Passing slowly through 600–900 °C precipitates carbide and sigma phases, so the quench follows the anneal without delay |
| Strain Hardened | Cold drawn after the anneal, with the strength taken from the reduction rather than from a furnace |
| Cold-Forming Limit | Heavy cold forming sends the section back through the stabilising anneal before it enters service |
| Stress-Relief Caution | A relief pass inside the sensitising band costs corrosion resistance, so the alternative is settled before it is booked |
| Post-Weld Anneal | Most joints enter service as welded, because niobium at eight times the carbon content keeps the weld zone stable |
Standards
ASTM B473 is the bar, rod and wire document behind this round bar, issued by ASTM International. Moreover, ASTM B462 covers forged sections of this round bar while ASTM B472 governs the billet it is reforged from.
| Standard | Product or Application |
|---|---|
| ASTM B473 / ASME SB473 | Bar, rod and wire, stabilised annealed |
| ASTM B462 / ASME SB462 | Forged bar, forging stock, flanges and fittings |
| NACE MR0175 / ISO 15156-3 | Sour service, at the condition that document sets |
Beyond that, the standards table on the Alloy 20 material page carries the European designations and the flat-product call-outs for this round bar.
Dimensions
The table below lists the round bar sizes we ship most often, while the route, the document and the lot size decide what else is possible. Please confirm your own size, section and length with the inquiry.
| Product Form | Typical Supply | Length |
|---|---|---|
| Round Bar | 6.35-250 mm dia., stabilised annealed to ASTM B473 | Cut to length or random |
| Hot-Finished Round Bar | 6.35 mm dia. and up, hot finished and descaled | Cut to length or random |
| Cold-Finished Round Bar | Above 12.7 mm dia., cold finished band | Cut to length |
| Peeled Round Bar | 20-250 mm dia., turned skin | Cut to length |
| Cold-Drawn Round Bar | 6.35-88.9 mm dia., strain hardened on request | Cut to length |
| Custom Round Bar | To drawing | Custom |
ASTM B473 splits this form by how it leaves the mill rather than by grade, so hot finished rounds begin at 0.25 in (6.35 mm) while cold finished rounds begin above 0.5 in (12.7 mm). In addition, tell us the finished diameter and the surface your shop expects.
Surface Finishes
The surface you order on this round bar decides how the part feeds, seals and resists attack. Consequently, we settle the condition of this round bar before the price goes out.
| Surface Condition | Typical Use |
|---|---|
| Stabilised Annealed and Pickled | The stabilising anneal followed by acid descaling leaves this round bar scale-free for acid plant work. |
| Cold Drawn | Drawing brings this round bar to a close diameter while the pass lifts proof stress into the strain-hardened band. |
| Peeled | A machined skin takes the scale off this round bar and leaves an even diameter behind it. |
In contrast, the surface finishes table on the Alloy 20 material page lists the further conditions open to this round bar.
Related forms from the same heat cover Alloy 20 Welding Wire, Alloy 20 Wire and Alloy 20 Bright Bar when your round bar order needs them.
TECHNICAL DOCUMENTATION
Download Technical Datasheet
Get detailed information including specifications, standards, dimensions and material properties.
HOW TO START
Start Your Order in 6 Simple Steps
A single coordinator stays with your Alloy 20 round bar enquiry from the first question to the loading bay. In addition, stock of this Alloy 20 round bar leaves inside fifteen days, and a freshly annealed heat takes about thirty.
1
Give Us the Duty
Send the acid, its concentration and its temperature together with the size, quantity and standard this round bar faces.
2
Settle the State
Then we lock the anneal cycle, the delivery condition and the tolerance band on this round bar.
3
Read the Offer
Pricing for this round bar comes back by size, quantity and destination port.
4
Sign off the Order
We need your written confirmation of the specification, the terms and the schedule for this round bar.
5
Book the Witness Points
Next we schedule any third-party inspection or dimensional review of this round bar before production starts.
6
Ship and Document
This round bar reaches you with mill papers, a packing list and the certificate set.
CERTIFICATIONS & QUALITY DOCUMENTATION
Certifications & Quality Documentation
Our production and inspection processes are certified to international standards, and every delivery ships with EN 10204 3.1 mill test certificates.
ISO 9001:2015
Quality Management System
PED 2014/68/EU
Pressure Equipment Directive
ASTM / ASME
Material Standards Compliance
EN 10204 3.1
Mill Test Certificates
FAQ
Frequently Asked Questions
Which standard covers this Alloy 20 round bar?
ASTM B473 and ASME SB473 cover this Alloy 20 round bar, with the ASTM B462 forging route taking over above the bar ceiling.
Does this round bar carry a hardness limit?
No. B473 prints tensile, yield, elongation and reduction of area with no hardness column, so we release this round bar on those four figures.
Does this round bar qualify for sour service?
Yes. NACE MR0175 covers this grade, and the condition it sets for your round bar is what we document per heat.
Which filler metal suits this round bar?
ER320LR bare wire to AWS A5.9 joins this round bar, with E320LR covered electrodes to AWS A5.4 for manual work.
Why does this round bar ship water quenched?
A slow pass through 600–900 °C precipitates carbide and sigma at the grain boundaries, so each round bar heat leaves the anneal straight into the tank.
Does a weld in this round bar need a post-weld anneal?
Usually not. Niobium at eight times the carbon content stabilises the matrix, so most round bar joints stay serviceable as welded.
What is your MOQ for this round bar?
Trial lengths of this round bar are welcome, and one piece covers most stock sizes.
What are your trade terms for this round bar?
Trade terms for this round bar open on FOB, and EXW, CIF or DAP follow once we know the destination port.
What is the lead time for this round bar?
Stock sizes of this round bar ship in 7 to 15 days, while a made-to-order annealed heat needs about 30 days.
Do you provide EN 10204 3.1 or 3.2 certificates for this round bar?
EN 10204 3.1 papers cover every heat of this round bar, and we can arrange a 3.2 endorsement.
REQUEST FOR QUOTATION
Need A Custom Alloy Solution?
Pricing for this Alloy 20 round bar comes back against B473 with the diameter, the delivery surface and the annealed state named. Send the acid, the size band and your quantity and we will work up the offer.
Your Alloy 20 round bar inquiry passes through the anneal, the finish and the document scope before any price goes out. We build to the signed sheet, and the full paper set travels with this round bar.
