Carbide Overlay Plate
When low-chromium welding wire is used in Carbide Overlay Plate, the formation of hard carbide phases is significantly reduced. This leads to lower hardness, weaker wear resistance, and a noticeably shorter service life.
- Description
Carbide Overlay Plate is a wear-resistant steel plate produced by welding a hardfacing alloy layer onto a steel base. One of the most important factors that determines its performance is the chemical composition of the welding wire, especially the chromium content.
When low-chromium welding wire is used, the microstructure and wear performance of the overlay layer change significantly.
Role of Chromium in Overlay Layer
Chromium is the key element in forming hard carbide structures during the welding process. These carbides (such as Cr₇C₃) are the main reason for high wear resistance.
When chromium content is reduced:
- Fewer hard carbide particles are formed
- The hardness of the overlay layer decreases
- The wear resistance becomes weaker
What Happens When Low Chromium Wire Is Used
Using low-chromium welding wire in Carbide Overlay Plate production leads to several changes in material performance.
1. Reduced Carbide Formation
Lower chromium content results in fewer and smaller carbide particles. The microstructure becomes more dominated by softer iron-based phases.
2. Lower Surface Hardness
Because carbides are the main hard phase, reduced chromium directly lowers surface hardness. This makes the surface more susceptible to abrasion.
3. Increased Wear Rate
Without sufficient hard carbide protection, the material wears faster under:
- Sliding abrasion
- Impact abrasion
- High-volume particle flow (sand, ore, clinker)
4. Reduced Service Life
The most important effect is shortened service life.
- High-chromium overlay plates: long-term wear resistance in severe environments
- Low-chromium overlay plates: faster wear and more frequent replacement
In many industrial applications, service life may be reduced significantly depending on working conditions.
Performance Comparison
| Chromium Level in Wire | Hardness Level | Wear Resistance | Service Life |
|---|---|---|---|
| High chromium (optimal) | Very high | Excellent | Long |
| Medium chromium | Moderate-high | Good | Medium |
| Low chromium | Low-moderate | Weak | Short |
Application Impact
Low-chromium Carbide Overlay Plate is generally not suitable for severe wear conditions such as:
- Mining and ore handling
- Cement clinker systems
- Coal transportation
- Heavy industrial abrasion zones
It may only be used in:
- Light abrasion environments
- Cost-sensitive applications
- Temporary or non-critical wear protection
