Piastra antiusura per rivestimento in carburo di cromo
IL Chromium Carbide Overlay layer is the heart of CCO wear plates, fornendo:
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High hardness for abrasion resistance
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Strong metallurgical bonding for toughness
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Customizable thickness for different industrial requirements
- Descrizione
Overlay di carburo di cromo (CCO) Wear Plates are bimetallic steel plates where a high-hardness chromium carbide layer is welded onto a base in acciaio resistente.
The overlay layer is the key component that provides the plate’s estrema resistenza all'usura, rendendolo ideale per minerario, cemento, energia, e applicazioni di movimentazione dei materiali.
Structure of the Chromium Carbide Overlay Layer
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Surface Layer (Carburo di cromo):
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Composizione: Mainly chromium (Cr) and carbon (C), often with small amounts of Ni, Mo, or Fe.
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Microstruttura: Denso, hard chromium carbide particles embedded in a metallic matrix.
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Durezza: Typically 58–65HRC, depending on grade and overlay thickness.
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Funzione: Provides high resistance to sliding wear and abrasion.
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Transition Zone:
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Scopo: Ensures metallurgical bonding between the overlay and the steel base.
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Caratteristiche: Slightly lower hardness than the surface, mantiene adhesion and toughness, and reduces risk of cracking.
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Steel Base Layer:
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Generalmente Q235, S355, NM400, or AR400/450.
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Scopo: Provides impact toughness and structural strength while supporting the hard overlay.
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Characteristics of the Overlay Layer
| Proprietà | Descrizione | Effect on Performance |
|---|---|---|
| Durezza (HRC) | 58–65 | Resists severe sliding and abrasive wear |
| Spessore (mm) | 3–20 | Adjusted according to application severity |
| Microstruttura | Chromium carbide particles in metallic matrix | High wear resistance with some toughness |
| Bonding Strength | Strong metallurgical weld with base | Prevents delamination during impact |
| Finitura superficiale | Shot-blasted or ground | Ensures consistent wear and smooth material flow |
Manufacturing Considerations of the Overlay
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Overlay Material Selection:
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Chromium carbide alloy wires, rods, or powders are used.
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Alloy composition affects durezza, resistenza all'usura, and cracking susceptibility.
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Processo di saldatura:
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Saldatura ad arco sommerso (SEGA): High deposition rate for large plates.
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Plasma Transferred Arc (PTA): Produces uniform hardness with low dilution.
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Saldatura ad arco con filo animato (FCAW) / SMAW: Flexible, for small plates or repairs.
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Overlay Thickness Control:
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Critical to ensure optimal wear life.
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Multi-pass welding builds up the desired thickness while maintaining surface hardness.
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Trattamento termico e sollievo dallo stress:
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Post-weld heat treatment may be applied at 150–200°C.
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Riduce tensione residua and prevents cracking during service.
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Surface Finishing:
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Grinding or shot blasting removes slag, spatter, e irregolarità.
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Garantisce uniform wear and consistent abrasion resistance.
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Applications of Chromium Carbide Overlay Layer
The overlay layer enables wear plates to perform in extremely abrasive and impact-heavy environments, compreso:
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Estrazione: Fodere del frantoio, hammer plates, ore hoppers
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Cemento & Concrete: Slurry chutes, mixer liners, screw conveyors
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Power Plants: Sistemi di movimentazione del carbone, scivoli per la cenere
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Riciclaggio & Gestione del materiale: Trituratori, piastre d'impatto, fodere per trasportatori
Key Advantages of the Overlay Layer
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Extreme Abrasion Resistance: Chromium carbide particles resist sliding wear and impact.
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Lunga durata: Properly designed overlays can last 5–10× longer than mild steel.
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Impact Support: Transition zone and base steel absorb energy, preventing delamination.
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Customizable Design: Spessore, durezza, and size can be tailored to application needs.
