When the Ball Mill pulverizes the material, the pressure roller of the Ball Mill wears faster, and the hot-rolled tire-type roll is replaced more frequently and can not be reused, so the cost is high, so most of the roller surfaces are currently surfaced. A method of surfacing a wear layer. In the following, the commonly used surfacing wear-resistant materials will be analyzed to provide a certain reference value for enterprises to select suitable materials.
Although the wear resistance of the material is related to hardness, hardness is not a decisive indicator. The higher the hardness, the better the wear resistance. The wear resistance of the metal material is closely related to the formation of the matrix of the material, the morphology, distribution and quantity of the carbide. When the Ball Mill rolls the material, the roller is impacted by the discontinuity and unevenness of the material, so the roll surface material is not only wearable but also has a certain impact resistance (toughness).
When the materials are different, the wear mechanism is different. The roll surface wear resistant material developed should also be different. To overcome the scratch wear and knife wear, a coarse hard phase is required, and to overcome the fatigue wear, a fine and dense hard phase is required to prevent small material particles from being inscribed on the surface of the roller to cause pre-cracking.
At present, there are many kinds of hardfacing materials such as Fe— Cr— B, Fe— Cw, Fe-Cr-C. The Cr, B and w elements are hard substances such as boride, tungsten carbide and iron boride. The addition of boron can refine the carbide and improve the impact properties. The excessive content of Cr and w makes the hard phase too brittle. Fe— Cr-B is the No. 3 alloy used for surfacing the surface of the workpiece of the brick press. Under the condition of quartz sand and white ash, the service life is 2.86 times higher than that of the original carburized and quenched template.
There are also many research workers who have improved the wear resistance and toughness by adding some other rare metals or other elements such as strontium and potassium to obtain some satisfactory results. For example, in the Fe-Cr-C surfacing consumable gold with potassium modifier, the research shows that the appropriate amount of potassium alloy modifier makes the Fe-Cr--C hardfacing alloy stronger and more resistant to cracking, and at the same time The low-stress abrasive wear wear resistance is greatly improved, and it does not peel off or crack under long-term work under strong impact load.
There is also a Fe-Cr— C— B alloy wear-resistant flux-cored wire developed for Ball Mills. In the industrial continuous crushing iron ore test, it not only has high impact resistance, but also has excellent resistance. The high-stress abrasive wear performance can be 1.5 times longer than that of the domestic high-chromium cast iron wear-resistant electrode.