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★ Chromium Carbide Overlay Plate is not all the same!
　　Chromium Carbide Overlay Plate was being manufactured by a relatively few firms forty years ago. It has excellent anti-abrasion feature which can endure medium impact, and it is widely used for resistance to severe wear. Currently, only 20 to 30 manufacturers in the world are producing this product. Due to different production technology, the anti-abrasion feature vary from 4 to 15 times compared with SS400 ordinary steel plates based on ASTM G65-1991 Dry Sand Wear Test. Currently, 80% of the manufacturers are still producing with first generation production technology, however, first generation production technology is unable to overcome the problem of dilution in the depositing process and only result in a range of 4 to 8 times of anti-abrasion feature. The latest third generation production can completely solve the problem of dilution, so the hard layer can be assured having a uniform hardness distribution and consistence of chemical compositions. Thus, the anti-abrasion feature can be reached up to 10 ~15 times. Due to the anti-abrasion feature of Chromium Carbide Overlay Plate is not all the same, thus, purchaser should pay more attention to verify the anti-abrasion feature prior concerning on the price.
　　There are only a few manufacturers that can produce Chromium Carbide Overlay Plate that having anti-abrasion feature of 12 to 15 times, such as VAULTID PLATE, UP-PLATE, ING-PLATE, and KSW PLATE. Some manufacturers claim that their products are having anti-abrasion feature of 30 to 50 times. As a matter of fact, they are not professional enough. Those manufacturers did not use AFS 50/70 standard sand, or, using standard sand repeatedly during the tests and caused the deviation. If a certain amount of tungsten carbide is added to Chromium Carbide Overlay Plate, the anti-abrasion feature can be increased to 22 to 25 times; But yet, the market does not accept its high cost.
★ How to Select Chromium Carbide Overlay Plates
　　The best way to select a good quality of Chromium Carbide Overlay Plate for purchase of large quantity is recommended as below:
★ The best way to make a right selection:
　　Request a sample plate from the manufacturer, and send it for ASTM G-65 wear test, base on the results of anti-abrasion feature as a reference. This is the most reliable way to verify which products are having a better anti-abrasion feature.

　　In case, it is difficult to perform the G-65 test due to high cost and time consuming. The following methods are recommended:
1.The Content of Cr & C：
Thickness of Hard Layer (mm)
Cr(%)
C(%)
Under 4mm
21~24
4.0~4.5
5mm
26~30
4.5~5.0
6mm above
30~34
5.0~5.5
2. Hardness distribution of Hard Layer :
　　It was proven that anti-abrasion feature is related to hardness in the equivalent chemical composition of Chromium Carbide Overlay Plate. Therefore a better solution is specified the hardness and chemical content to make sure obtaining better anti-abrasion of Chromium Carbide Overlay Plate. The relation of hardness and anti-abrasion is shown in below chart in statistics.
 
　　Hardness test should be done not only on the plate’s surface. In order to make sure the hardness of hard layer is consistent, it is recommended that hardness test should be carry out in the hard layer by Vickers Hardness Test Method 30kgf as below :
3. Smoothness of the surface：
　　While selecting, the smoothness and evenness of the welding seam should be observed, ensure that the hard layer is equal in thickness, to prevent the thinner part to be worn out first.
4. The fusing of Hard Layer and Backing Plate：
　　The hard layer of this product is welded on a steel plate (material of the backing plate could be ordinary steel plate, stainless steel or high tensile steel plate). So materials can be completely fused into one piece, and should not have the problem of falling apart. However, when welding is not done correctly, defects might still occur. Thus, dye check (Dye Penetrate Method) should be used to check for cracks between the welding and backing plate.
5. Fine cracks on the hard layer:
　　Fine crack lines always occur on hard layer because of the stress release, but it won’t affect the wear resistance feature and will not peeling off. Generally, higher hardness will get finer crack lines. Also, crack pitch can be used to evaluate the hardness and anti-abrasion feature, i.e. closer crack pitch means higher hardness and have better anti-abrasion feature.