ECoCr-C Cobalt 1 Welding Electrode — Stellite® 1 | AWS A5.13 Supplier in India
Nicorex Alloys is an ISO 9001 and ISO 14001 certified importer, stockist, and supplier of cobalt-chromium hardfacing consumables based in Mumbai, India. We maintain a ready stock of ECoCr-C (Cobalt 1) coated electrodes in compliance with the AWS A5.13 / ASME SFA 5.13 with competitive pricing, EN 10204/3.1B mill test certificates, and expedited dispatch for project-critical requirements.
Delivering a high deposit hardness at 50–58 HRC, the ECoCr-C electrode builds a hypereutectic microstructure containing roughly 19% primary chromium carbides. AWS A5.13 specifies carbon at 1.7–3.0%, chromium at 25–33%, tungsten at 11.0–14.0%, and cobalt balance. The very high tungsten and carbon content makes ECoCr-C the default choice where extreme abrasive wear outweighs impact loading. UNS designations are W73001 (electrode) and R30001 (alloy). Trade equivalents include Stellite® 1, Cobalt Alloy 1, CoCr-C, and Stoodite 1. Hot hardness holds above 760°C (1400°F). Electrode diameters span 2.4 to 5.0 mm; polarity is DCEP.
ECoCr-C is the most crack-sensitive standard cobalt electrode. Welding is restricted to flat position only, deposits are limited to 2 layers maximum, and finishing must be done by grinding; the hypereutectic carbides are too hard for carbide tool inserts. Key applications these ECoCr-C cobalt 1 welding electrode is used in include pump sleeves, rotary seal rings, crusher parts, valve heads in extreme-erosion service, wear pads, drawing blocks, and expeller screws.
ECoCr-C Coated Electrode Technical Specifications
| AWS Classification | ECoCr-C |
|---|---|
| UNS Designation | W73001 (electrode) / R30001 (alloy) |
| Governing Specification | AWS A5.13 / A5.13M:2010 |
| ASME Specification | SFA 5.13 |
| Welding Process | SMAW (Shielded Metal Arc Welding) |
| Electrode Coating | Rutile-basic |
| Polarity / Current | DCEP (DC+) |
| Welding Positions | Flat only |
| Deposit Hardness | 50–58 HRC (undiluted); 46–50 HRC (2-layer SMAW) |
| Alloy Base | Cobalt-Chromium-Tungsten (Co-Cr-W) |
| Machinability | Grind only — cannot be machined |
What Does the AWS Classification ECoCr-C Mean?
| Character(s) | Meaning |
|---|---|
| E | Electrode — covered/coated electrode for SMAW |
| Co | Cobalt-base alloy deposit |
| Cr | Chromium is the principal alloying element after cobalt |
| -C | Variant ‘C’ — the highest carbon and highest tungsten in the standard series. C 1.7–3.0%, W 11.0–14.0%. Produces a hypereutectic microstructure with ~19% primary carbides. |
Weld Deposit Chemical Composition of ECoCr-C (%)
| Element | Carbon (C) | Chromium (Cr) | Tungsten (W) | Cobalt (Co) | Iron (Fe) | Nickel (Ni) | Silicon (Si) | Manganese (Mn) | Molybdenum (Mo) |
|---|---|---|---|---|---|---|---|---|---|
| AWS A5.13 Requirement (%) | 1.7 – 3.0 | 25 – 33 | 11.0 – 14.0 | Remainder | 5.0 max | 3.0 max | 2.0 max | 2.0 max | 1.0 max |
| Element | Carbon (C) | Chromium (Cr) | Tungsten (W) | Cobalt (Co) | Iron (Fe) | Nickel (Ni) | Silicon (Si) | Manganese (Mn) | Molybdenum (Mo) |
|---|---|---|---|---|---|---|---|---|---|
| Typical Deposit (%) | 2.1 | 29.6 | 12.1 | Balance | 2.3 | 1.9 | 0.9 | 0.1 | 0.1 |
Compared to ECoCr-A and ECoCr-B, ECoCr-C’s tungsten is at 11.0–14.0% (vs 3.0–6.0% and 7.0–9.5%) and carbon at 1.7–3.0% (vs 0.7–1.4% and 1.0–1.7%). These wider ranges push the microstructure past the eutectic point into a hypereutectic carbide network.
ECoCr-C Deposit Hardness & Wear Performance
| Condition | Hardness |
|---|---|
| Alloy Specification (undiluted) | 50 – 58 HRC / 550–720 HV |
| 2-Layer SMAW Deposit | 46 – 50 HRC |
| Weld Metal Deposit (multi-layer) | 50–56 HRC / 520–620 HV |
| Full Hardness Range (1st layer through undiluted) | 43–58 HRC |
| Hot Hardness Retention | Above 760°C (1400°F) |
| Density | 8.69 g/cm³ |
| Seawater Electrode Potential | approx. –0.4 V (SCE) |
| Property | Rating |
|---|---|
| Abrasion Resistance | Excellent |
| Impact Resistance | Fair |
| Corrosion Resistance | Good |
| Hot Weld Hardness | Excellent |
| Machinability | Grind only |
| Deposit Cross-Checking | Some cracking possible |
| Maximum Layers | 2 |
First-layer deposits on carbon steel show reduced hardness (~38–45 HRC) due to iron dilution. Two layers are needed to approach specification chemistry. Unlike ECoCr-A and ECoCr-B, where 3 layers are standard, ECoCr-C is limited to 2 layers maximum because additional passes compound thermal stresses and raise crack risk.
Electrode Sizes & Verified Welding Parameters for ECoCr-C
| Diameter | Length | Current (DCEP) |
|---|---|---|
| 2.4 mm (3/32″) | 300 mm (12″) | ~60 – 90 A |
| 3.2 mm (1/8″) | 350 mm (14″) | 90 – 120 A |
| 4.0 mm (5/32″) | 350 mm (14″) | 135 – 180 A |
| 4.8 mm (3/16″) | 400 mm (16″) | ~155 – 200 A |
Position: Flat only. Arc technique: Short arc, narrow stringer beads, avoid all weaving. Preheat: 150–315°C typical; up to 400°C for high-CE or thick sections. Post-weld: Mandatory slow cool in dry vermiculite or insulating blanket. Buffer layer: Strongly recommended (309L or Inconel 625) on all substrates.
Get ECoCr-C Cobalt 1 Welding Electrode at Competitive Prices
Industrial Applications of ECoCr-C (Cobalt 1) Hardfacing Electrode
- Crusher parts, mixer blades, screw press components, and expeller screws in the mining and aggregate industries. ECoCr-C’s 50–58 HRC deposit withstands the most aggressive particulate erosion, where ECoCr-A and ECoCr-B wear prematurely.
- Valve heads and seat faces in severe erosive service. Sand-laden choke valves, high-velocity steam valves, and erosive chemical environments.
- Flat wear surfaces are subject to severe sliding or abrasive contact under high load. Drawing blocks in wire/tube operations, wear pads on heavy equipment, and screw press components. The flat-position-only welding restriction suits these horizontal surface applications naturally.
Storage, Handling & Reconditioning of ECoCr-C Electrodes
- Sealed packaging: no pre-baking required
- After opening: heated holding oven 100-150°C
- Reconditioning: 150°C for 1 hour if exposed to humidity
- Exposure limit: 4 hours max outside oven
- Re-drying: maximum 2 cycles
- CRITICAL for ECoCr-C: Any moisture contamination dramatically increases cold cracking risk due to the high carbide content and low ductility of the deposit.
INTEGRITY NOTE: This is a general cobalt electrode storage practice; no ECoCr-C-specific storage datasheet found.
How to Order ECoCr-C (Cobalt 1) Hardfacing Electrode from Nicorex Alloys
-
Electrode Type - SMAW hardfacing; AWS A5.13: ECoCr-C
-
Size - 3.2 mm, 4.0 mm, 4.8 mm, 6.4 mm; electrodes
-
Current Type - DCEP or AC
-
Welding Position - Flat and horizontal (1G, 2G) only
-
Material Grade - Cobalt 1 / Stellite 1; UNS R30001; W.Nr. 2.4779; EN ISO 14700: E Co Cr-C
-
Quantity - Specify number of cans or total kg required
-
Standard - AWS A5.13 / ASME SFA-5.13; EN ISO 14700; ASME Section IX
-
Documentation - MTC EN 10204 3.1/3.2; PMI Report; Hardness Report (HRC 48–55); TPI certificate
-
Packaging - Hermetically sealed metal cans; ISPM 15 compliant export cartons
- Delivery Destination - Domestic / International; specify port or delivery address
Frequently Asked Questions
What is the Price of ECoCr-C Cobalt 1 Electrode per Kg in India?
ECoCr-C pricing varies by diameter, order volume, and cobalt market rates. As the hardest standard cobalt electrode, ECoCr-C costs more than ECoCr-A and ECoCr-B. Contact Nicorex Alloys for the latest quotation with MTC 3.1 documentation.
What is the Maximum Number of Layers for an ECoCr-C Weld Overlay?
2 layers maximum are allowed for an ECoCr-C weld overlay. The ~19% primary carbide volume and very high carbon (1.7–3.0%) make the deposit extremely crack-sensitive. Additional layers compound thermal stresses.
What Preheat Temperature is Required Before Welding ECoCr-C on Carbon Steel?
Does ECoCr-C Retain Its Hardness Above 750°C?
Yes. ECoCr-C retains functional hardness above 760°C (1400°F) (the highest temperature rating in the standard cobalt series).