Cobalt-Based Alloy 21 Welding Wire – Specifications, Applications & Supply
Introduction to Cobalt-Based Alloy 21 Welding Wire
Cobalt-based alloy 21 welding wire is a high-performance hardfacing material formulated with a balanced cobalt-chromium-nickel-molybdenum composition. Designed for severe operating conditions, it delivers consistent weld quality, stable arc performance, and a favorable combination of wear resistance, corrosion resistance, and high-temperature strength. As a reliable option for industrial hardfacing, this welding wire serves as a practical solution for component repair and surface reinforcement across critical sectors.
Our company manufactures and supplies cobalt-based alloy 21 welding wire from Hebei, China. We focus on quality control, punctual delivery, and responsive service, supporting global clients with dependable welding materials and stable supply chains.
Key Specifications & Popular Sizes
We provide cobalt-based alloy 21 welding wire in solid and cored types with widely adopted diameters for industrial use:
Common Diameters (mm)
1.2 mm – Popular for automatic welding and precision hardfacing
1.6 mm – Versatile for general repair and production
2.4 mm – Suitable for heavy-duty overlay and build-up
3.2 mm / 4.0 mm – Used for large components and high-volume surfacing
Standard Lengths
Straight lengths: 300 mm–1000 mm
Spool lengths: Customized based on requirements
Chemical Composition (Typical, wt%)
Co: Balance
Cr: 19–21
Ni: 15–18
Mo: 3–4
C: 0.2–0.3
Si/Mn/Fe: Trace
Weld Deposit Hardness
As-welded: 33–38 HRC
Work-hardened: 45–48 HRC
Packaging & Packaging Specifications
To ensure safe transit and convenient storage, we adopt industry-standard packaging for cobalt-based alloy 21 welding wire:
Spools: 15 kg/spool (common for 1.2 mm–2.4 mm wires)
Carton boxes: 20 kg/box (for straight wires or spools)
Vacuum-sealed aluminum foil bags: For moisture resistance and long-term storage
Custom packaging available upon request
Core Performance Parameters (Recognized by Buyers)
Cobalt-based alloy 21 welding wire is valued for balanced mechanical and chemical properties: Wear resistance: Resists metal-to-metal sliding wear, abrasion, and cavitation; suitable for moderate to heavy wear conditions.
Corrosion resistance: Withstands oxidation, acids, alkalis, and chloride-containing media; performs well in 60–90 °C mixed acid environments.
High-temperature stability: Maintains performance at 700–850 °C; short-term resistance up to 900 °C; resists thermal fatigue and oxidation.
Toughness & impact resistance: Low-carbon design with nickel addition reduces cracking risk under thermal cycling and mechanical shock.
Machinability: The deposit can be machined with standard tools, enabling post-weld finishing for precise components.
Primary Application Fields
Cobalt-based alloy 21 welding wire is widely used in industries requiring wear, corrosion, and high-temperature resistance:
Oil & gas: High-pressure valves, seats, stems, and wellhead components; resists corrosive media and mechanical wear.
Power generation: Boiler nozzles, turbine seals, and valve trim; withstands high-temperature flue gas and thermal shock.
Chemical processing: Pump sleeves, agitator blades, and reactor internals; handles acids, alkalis, and erosive slurries.
Metallurgy & forging: Hot stamping dies, forging dies, and shear blades; resists high-temperature wear and impact.
Marine & hydraulic: Propeller components, hydraulic valves, and pump impellers; provides cavitation and corrosion resistance.
Why Choose Our Cobalt-Based Alloy 21 Welding Wire?
1. Strict Quality Control
We implement standardized production processes and multi-point quality inspection. Each batch undergoes chemical composition analysis, hardness testing, and arc performance evaluation to ensure consistency and reliability.
2. Direct Supply from Hebei, China
As a manufacturer based in Hebei, we maintain stable production capacity and efficient logistics. We support flexible order quantities—from small-batch trial orders to large-volume bulk supply—with reliable lead times.
3. Punctual Delivery & Reliable Commitment
We adhere to agreed delivery schedules. With in-stock availability for popular specifications (1.2 mm, 1.6 mm, 2.4 mm), we arrange prompt shipment to minimize customer downtime.
4. Customer-Focused Service
Our technical team provides professional support, including welding procedure guidance, parameter recommendations, and application-specific suggestions. We offer clear communication, quick response to inquiries, and tailored solutions for unique requirements.
5. Cost-Effective Pricing
By optimizing production and supply chain management, we deliver competitive pricing without compromising quality, helping customers reduce overall operational costs.
Notes
Cobalt-based alloy 21 welding wire is a dependable choice for high-demand industrial hardfacing. With balanced performance, multiple specifications, and secure packaging, it meets diverse application needs. Our Hebei-based factory stands ready to support your projects with quality products, on-time delivery, and attentive service.
Contact us today to discuss your requirements, request technical data, or place an order.