440C, 1.4125 and SUS440C Stainless Steel Bars
Short Answer for 440C and 1.4125 Stainless Bar Buyers
Junxiong Metal can review martensitic stainless steel bar enquiries using AISI 440C, UNS S44004, EN 1.4125 or SUS440C terms. Buyers must state the governing standard, product form, dimensions, tolerance, supplied and final heat-treatment condition, hardness or property requirements, corrosion and wear duty, quantity, destination and MTC scope.
440C, UNS S44004, 1.4125 and SUS440C are commonly compared, but the alias chain is not a complete purchase specification. Heat treatment, hardness, surface quality, dimensional allowance and service environment strongly affect suitability and must be agreed for each order.
Send a complete 440C, 1.4125 or SUS440C factory RFQ or send the grade, standard, shape, size, condition and quantity by WhatsApp.
Representative Junxiong Stainless Bar and Packing Images


Image boundary: steel grade, microstructure and hardness cannot be verified from appearance. These images support product-form and packing discussions only and are not 440C batch evidence.
Supply Scope and Evidence Boundary
Junxiong has confirmed commercial supply capability for this grade family. The page must not promise a hardness level, wear life, corrosion resistance or specific stock without matching condition data and order or batch evidence.
Evidence boundary: a supply statement or quotation is not a shipment record, current-stock declaration, heat certificate or dimensional inspection report. Each order is confirmed against the approved specification, production route and order or batch documents.
Technical Facts Buyers Must Confirm
| Decision | Required RFQ information |
|---|---|
| Grade route | AISI 440C, UNS S44004, EN 1.4125, SUS440C or another buyer-approved standard and edition. |
| Heat-treatment route | State supplied condition, downstream hardening and tempering route, target hardness or properties and distortion allowance. |
| Service requirement | Describe wear, contact stress, corrosion environment, lubrication and dimensional-stability requirements for buyer engineering review. |
| Dimensions | Finished size, tolerance, straightness, surface condition, grinding or machining allowance and length tolerance. |
| Inspection | Heat identity, MTC type, chemistry, hardness, microstructure, decarburization or supplementary inspection requirements. |
| Commercial data | Quantity per size, repeat demand, packing, destination country, port and required delivery schedule. |
Shape and RFQ Selection
| Shape | Buyer must state | Factory review |
|---|---|---|
| Round bar | Diameter, tolerance, straightness, surface, length and bar-feeder or machining requirements. | Starting material, process route, tooling, inspection, MOQ and schedule are reviewed for the exact grade-size-condition combination. |
| Square bar | Side size, tolerance, corner radius, twist, straightness and length. | Starting material, process route, tooling, inspection, MOQ and schedule are reviewed for the exact grade-size-condition combination. |
| Flat bar | Width, thickness, edge condition, flatness, straightness and length. | Starting material, process route, tooling, inspection, MOQ and schedule are reviewed for the exact grade-size-condition combination. |
| Hexagonal bar | Across-flats size, tolerance, twist, straightness and length. | Starting material, process route, tooling, inspection, MOQ and schedule are reviewed for the exact grade-size-condition combination. |
| Custom profile | Dimensioned drawing, critical tolerances, corner radii, datum scheme, annual demand and trial quantity. | Starting material, process route, tooling, inspection, MOQ and schedule are reviewed for the exact grade-size-condition combination. |
1.4112 Steel and X90CrMoV18 Need a Separate Buyer Review
Junxiong can review 1.4112 steel and X90CrMoV18 bar enquiries, but this route must not be folded into 1.4125 or AISI 440C. Both are hardenable martensitic stainless routes used in wear-led applications, while their designations, chemistry limits, product availability, heat treatment and acceptance documents remain separate purchase decisions.
| Buyer term | Primary-source context | Quotation rule |
|---|---|---|
| EN 1.4112 / X90CrMoV18 | Swiss Steel lists Durapur 4112 as a hardenable, wear-resistant martensitic grade. Zapp lists 1.4112 precision-wire and profile routes without assigning one universal AISI identity in its current product table. | State EN 1.4112 or X90CrMoV18, the governing product standard and edition, shape, condition, dimensions, heat-treatment plan and MTC requirements. |
| AISI 440B search term | One Zapp producer comparison describes 1.4112 as AISI 440B context, while producer availability tables may leave the AISI field blank. | Treat 440B as a buyer search or producer-comparison term until the controlling standard and chemistry are approved. Do not substitute from the nickname alone. |
| EN 1.4125 / X105CrMo17 / AISI 440C | This page’s main 440C route has a different designation and composition decision from 1.4112. | Keep 1.4112 and 1.4125 as separate quotation lines and require matching heat-specific documents. |
Supply boundary: review capability is not a stock promise. Actual shape, size, condition, manufacturing route, minimum quantity, schedule and inspection evidence must be confirmed for the order.
Standards and Primary Reference Sources
- ASTM A276/A276M-25: the active ASTM specification for stainless steel bars and shapes.
- BS EN 10088-3:2023: technical delivery conditions for stainless bars, rods, sections and bright products.
- JIS G 4318:2016: the active Japanese standard route for cold-finished stainless steel bars.
- worldstainless Martensitic Stainless Steels: Industry technical guide listing the 440C and 1.4125 designation family and explaining martensitic stainless context.
- worldstainless ISO 15510 grade comparison: International designation comparison reference; it does not replace the governing product standard or order certificate.
- Swiss Steel stainless-steel brochure: official producer context identifying 1.4112 / X90CrMoV18 as a hardenable, wear-resistant martensitic route.
- Zapp precision stainless-steel range: current producer availability table listing 1.4112 separately from 1.4125 / AISI 440C.
- Zapp 9.9440YL comparison data sheet: producer comparison using a 1.4112 / AISI 440B context; this is not a universal equivalence rule or Junxiong batch certificate.
Reference boundary: publisher, association and mill pages support terminology and buyer verification. They are not Junxiong heat certificates and do not prove that every designation, product form or delivery condition is interchangeable.
Buyer Checklist Before Quotation
- Exact grade designation, governing standard and standard edition.
- Shape, finished dimensions and machining allowance.
- Dimensional tolerance, straightness, twist and corner-radius limits.
- Delivery and heat-treatment condition.
- Surface condition and defect limits.
- Supplied and final heat-treatment route, target hardness and grinding or machining allowance.
- MTC, heat traceability and third-party inspection requirements.
- Quantity per size, repeat demand, destination, schedule and packing.
FAQ for 440C and 1.4125 Stainless Bar Buyers
Can Junxiong supply 440C cold-finished round bar?
Junxiong can review the requirement after receiving the standard, diameter, tolerance, surface, supplied condition, final heat-treatment plan, hardness target, quantity and destination.
Are 440C, 1.4125 and SUS440C automatically interchangeable?
No automatic substitution is assumed. They are useful international comparison terms, while the governing standard, condition, testing and required properties control acceptance.
Why is heat treatment central to a 440C RFQ?
Hardness, wear behavior, corrosion performance and dimensional change depend on the approved process and condition. The grade name alone is insufficient.
Can flat, square or custom 440C sections be reviewed?
Yes, subject to starting material, condition, tooling, reduction route, tolerances, machining allowance and quantity.
Can hardness and microstructure testing be specified?
Yes. The buyer must state the test methods, locations, acceptance criteria and certificate requirements before production.
Is 1.4112 steel the same as 1.4125 or 440C?
No. 1.4112 / X90CrMoV18 and 1.4125 / X105CrMo17 follow separate designation and chemistry routes. They may appear in the same high-hardness martensitic selection discussion, but the purchase order and MTC must identify the approved grade.
Can a buyer specify 1.4112 by writing only 440B?
No automatic substitution is assumed. Some producer literature uses a 440B comparison, while other producer tables do not assign one universal AISI identity. State the governing standard, exact designation and required limits.
Related Cold Drawn Steel Pages
- Cold drawn round steel bar
- Cold drawn square steel bar
- Cold drawn flat steel bar
- Cold drawn hexagonal steel bar
- Custom cold drawn steel profiles
- Cold drawn stainless steel bars and profiles
- 17-4PH, 630, 1.4542 and SUS630 stainless steel bars
- 420F, 420FSe and SUS420F free-machining stainless steel bars as a separate martensitic procurement route, not a 440C substitute.
- Factory and quality verification
Send the complete 440C, 1.4125 or SUS440C specification for factory review.