| Plate Type | Chromium carbide overlay plate, produced by welding a wear-resistant alloy onto a carbon-steel backing plate | Confirms that the product is a composite wear plate rather than a homogeneous alloy plate | Choose CCO when abrasive wear is the main failure mechanism and moderate impact resistance is acceptable |
| Backing Plate Material | Low-carbon or mild structural steel; typically weldable carbon steel | The backing plate provides structural support, toughness, and a surface for installation or welding | Use a thicker backing plate for chutes, liners, and panels exposed to impact or structural loading |
| Typical Chemical Composition of Overlay | Approximately 4–5% carbon, 20–30% chromium, with iron as the balance; alloy additions may include manganese, silicon, molybdenum, or niobium | Carbon and chromium form hard chromium carbides that resist cutting, sliding, and gouging abrasion | Select the chemistry according to abrasive mineral hardness, impact level, temperature, and corrosion exposure |
| Overlay Thickness | Commonly 3–20 mm; special fabrication may use thinner or thicker deposits | Greater thickness generally provides more usable wear allowance but increases weight and may reduce flexibility | Use 3–6 mm for light-duty liners, 6–12 mm for general material handling, and 12–20 mm for severe abrasion |
| Backing Plate Thickness | Commonly 4–25 mm, depending on structural and impact requirements | Controls stiffness, mounting strength, resistance to deformation, and total panel weight | Choose a thicker backing for large unsupported panels, impact zones, and bolted structural liners |
| Overlay Hardness | Typically about 55–65 HRC; hardness may vary through the deposit and between production methods | Higher hardness usually improves resistance to sliding and mineral abrasion, but does not automatically improve impact performance | Use the lower end for impact-prone service and the higher end for predominantly sliding abrasion |
| Carbide Volume Fraction | Often approximately 30–40% chromium carbide by volume in conventional CCO deposits | A higher carbide fraction can improve abrasive wear resistance, while excessive carbide content may reduce toughness | Choose a balanced carbide fraction for applications combining abrasion and repeated impact |
| Wear Test Reference | ASTM G65 dry-sand/rubber-wheel testing is commonly used for comparative abrasion evaluation | A standardized test helps compare products, but laboratory results may not duplicate actual service conditions | Request the test method, procedure, load, abrasive, and mass-loss result rather than relying only on a hardness value |
| Impact Resistance | Moderate; CCO is generally less impact-tolerant than tough alloy steel or manganese steel | Hard carbide-rich deposits can crack under heavy, repeated impact even when the overlay remains wear-resistant | Use CCO for sliding or low-to-moderate impact; consider tougher materials for severe impact loading |
| Typical Operating Temperature | Often suitable for dry service up to approximately 500–600°C, subject to alloy design and thermal cycling | High temperature can change hardness, cause distortion, or introduce thermal stresses in the overlay and backing plate | Confirm the supplier’s temperature limit for continuous service, peak exposure, and thermal cycling before selection |
| Crack Pattern | Transverse stress-relief cracks are common in many CCO overlays | Visible cracks may be intentional and help relieve welding stress; unacceptable cracks are those that reach the backing or cause separation | Specify allowable crack spacing, crack depth, and inspection requirements for critical liners |
| Flatness and Dimensional Tolerance | Depends on plate size, overlay thickness, welding heat input, and straightening process | Poor flatness can create installation gaps, uneven wear, and additional fabrication work | Define maximum bow, camber, length, width, and thickness tolerances before ordering |
| Fabrication and Cutting | Can generally be cut by plasma, waterjet, or abrasive methods; conventional oxy-fuel cutting may be limited by the overlay | The cutting method affects heat-affected zones, edge quality, dimensional accuracy, and tool life | Use waterjet for precise profiles, plasma for common fabrication, and follow approved procedures for drilling and welding |
| Weldability and Attachment | The carbon-steel backing is generally weldable; the carbide overlay normally requires controlled procedures | Incorrect welding can cause cracking, distortion, hydrogen-related defects, or detachment from the backing | Prefer bolting or welding to the backing plate when possible, and follow preheat, interpass, consumable, and heat-input requirements |
| Best-Fit Applications | Chutes, hoppers, transfer points, screens, crushers, feeders, conveyor liners, fans, and material-handling equipment | These applications commonly experience sliding abrasion from coal, minerals, sand, clinker, ore, or other bulk solids | Match plate thickness, hardness, and backing strength to the material flow rate, particle size, impact energy, and maintenance plan |