In the wear protection industry, one of the most common ways to evaluate a bi-metal wear plate is by checking two parameters:
- Chemical composition of the hardfacing layer
- Surface hardness (HRC)
While these indicators are important, they do not tell the whole story.
Relying solely on chemical analysis and hardness is similar to judging the quality of a meal by measuring its ingredients rather than tasting the final dish.
The “Recipe” Does Not Guarantee the Result
Imagine two chefs using exactly the same ingredients:
- Premium beef
- High-quality spices
- Identical cooking oil
Would the two dishes necessarily taste the same?
Of course not.
The final result depends on much more than the ingredients themselves. It depends on the recipe, cooking process, temperature control, and the chef's expertise.
The same principle applies to wear-resistant plates.
Two manufacturers may advertise similar specifications:
- Chromium (Cr): 25–30%
- Carbon (C): 4–5%
- Hardness: 58–63 HRC
Yet their products can exhibit dramatically different service lives under identical operating conditions.
Why Chemical Composition Is Only Part of the Story
The wear resistance of a hardfaced plate is determined not only by the amount of alloying elements but also by how those elements are transformed during the welding process.
Several critical factors influence the final performance:
1. Microstructure
The same chemical composition can produce significantly different microstructures:
Fine carbides
Coarse carbides
Uniform carbide distribution
Non-uniform carbide distribution
Since carbides are the primary wear-resistant phase, their morphology and distribution have a direct impact on abrasion resistance.
2. Carbide Formation Efficiency
Not all chromium and carbon become wear-resistant carbides.
The effectiveness of carbide formation depends on:
Welding parameters
Dilution rate
Cooling conditions
Flux and alloy design
As a result, two wear plates with identical chemical compositions may deliver completely different wear performance.
3. Manufacturing Process Control
Wear plate quality is strongly affected by:
Heat input
Welding speed
Overlay thickness control
Dilution management
Residual stress control
These factors cannot be identified simply by looking at a chemical analysis report.
Harder Does Not Always Mean Better
Another common misconception is:
"The harder the plate, the better the wear resistance."
In reality, hardness alone does not guarantee longer service life.
A plate with slightly lower hardness but a higher volume fraction of well-distributed carbides may outperform a harder plate with a less optimized microstructure.
Wear resistance is a combination of hardness, toughness, carbide structure, and overall metallurgical quality.
ASTM G65: Measuring Real Wear Performance
At BCC, we believe customers should evaluate wear plates based on actual wear resistance rather than specifications alone.
That is why, in addition to chemical composition and hardness testing, we conduct abrasion resistance testing according to ASTM G65.
What Is ASTM G65?
ASTM G65 is one of the world's most widely recognized standards for evaluating abrasion resistance.
The test uses:
A rotating rubber wheel
Standardized abrasive sand
Controlled loading conditions
During the test, the specimen is exposed to continuous abrasive wear under repeatable laboratory conditions.
The performance is then measured by:
Weight loss
Volume loss
The lower the material loss, the higher the abrasion resistance.
Unlike hardness testing, ASTM G65 evaluates the actual outcome of the entire manufacturing process.
From Ingredients to Performance
Chemical composition tells us what ingredients were used.
Hardness tells us one property of the finished product.
ASTM G65 tells us how the product actually performs.
In other words:
Chemical analysis evaluates the recipe.
Hardness evaluates one characteristic.
ASTM G65 evaluates the final result.
This is why leading mining, cement, steel, and power-generation companies increasingly use abrasion testing data when selecting wear-resistant materials.
The BCC Approach: Performance-Based Quality Evaluation
To ensure consistent and measurable quality, BCC evaluates wear plates through a comprehensive verification process:
Step 1 – Chemical Composition Analysis
Verification of:
- Carbon (C)
- Chromium (Cr)
- Niobium (Nb)
- Boron (B)
- Other alloying elements
Step 2 – Hardness Testing
Measurement of overlay hardness and consistency.
Step 3 – Microstructure Examination
Evaluation of:
Carbide morphology
Carbide density
Phase distribution
Step 4 – ASTM G65 Abrasion Testing
Direct measurement of wear resistance under standardized conditions.
Questions Every Customer Should Ask
Instead of asking only:
❌ What is the chromium content?
❌ What is the hardness?
Consider asking:
✅ What is the ASTM G65 wear loss result?
✅ Is there an independent test report available?
✅ What is the carbide structure?
✅ What field performance data supports the product?
These questions provide a much clearer picture of the true value of a wear-resistant plate.
Beyond Specifications: Proven Performance
At BCC, we believe that quality should be demonstrated through performance, not just numbers on a certificate.
By combining:
✔ Chemical composition analysis
✔ Hardness testing
✔ Metallurgical examination
✔ ASTM G65 abrasion testing
we provide customers with wear solutions that are validated by engineering data and proven in real-world applications.
BCC D-Plate® – Wear Resistance Proven by Performance.
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