In modern industrial manufacturing systems, diamond micropowder, with its unique physical properties, has become a core raw material in the manufacturing of various high-performance abrasives. These abrasives play an indispensable role in many industries such as mechanical processing and hardware manufacturing, profoundly affecting product quality and production efficiency.

I. Types of Abrasives and the Incorporation of Diamond Micropowder

1. 1. Grinding Wheels
   • (1) Structure and Manufacturing: Grinding wheels are a common type of abrasive, composed of abrasives, binders, and pores. In the manufacturing of diamond grinding wheels, diamond micropowder serves as the abrasive, with particle sizes ranging from a few micrometers to tens of micrometers depending on the processing needs. For example, grinding wheels used for precision grinding may use diamond micropowder with a particle size of 5-15 micrometers; while grinding wheels for rough grinding will have larger micropowder particle sizes, around 20-50 micrometers. These micropowders are mixed evenly with specific binders (such as ceramic, resin, or metal binders), then processed through pressing and sintering to create grinding wheels with a specific shape and strength.
   • (2) Working Principle: When the grinding wheel is installed on equipment such as a grinding machine and rotated at high speed, the surface diamond micropowder acts like countless tiny cutting edges, contacting the surface of the material being processed. Due to diamond's high hardness, it can easily cut metal and non-metal materials, removing excess material from the surface and achieving precise control over the part's size accuracy and surface shape.
2. 2. Abrasive Belts
   • (1) Construction and Production: Abrasive belts consist of a substrate, abrasive, and adhesive. In the manufacturing of abrasive belts, diamond micropowder is evenly attached to the flexible substrate material (such as cloth, paper, or composite substrates) through a special bonding process. The choice of adhesive is crucial; it needs to ensure that the diamond micropowder is firmly fixed to the substrate while gradually releasing the micropowder during processing as the abrasive belt wears, maintaining continuous grinding ability. For example, in producing abrasive belts for metal polishing, diamond micropowder with a particle size of 1-10 micrometers is used. Advanced processes like electrostatic sandblasting ensure the micropowder is vertically and evenly distributed on the substrate surface. Multiple layers of adhesive are applied and cured to produce a high-performance diamond abrasive belt.
   • (2) Application Characteristics: When working, abrasive belts rely on contact friction with the workpiece surface for grinding and polishing. Because abrasive belts have a certain flexibility, they can adapt to the processing of workpieces with various complex shapes, offering unique advantages in curved surface processing and large-area planar processing. Compared to grinding wheels, abrasive belts have better heat dissipation during processing, preventing local overheating from burning the workpiece surface. They are especially suitable for processing applications with high surface quality requirements.
3. 3. Abrasive Paste
   • (1) Composition and Preparation: Abrasive paste is a paste-like abrasive material mainly composed of diamond micropowder, oily carriers, and auxiliary additives. The content and particle size of diamond micropowder in the abrasive paste are adjusted according to different Applications. For high-precision mirror polishing, extremely fine diamond micropowder is usually used, such as 0.1-1 micrometer; while for general grinding, the micropowder particle size can be slightly larger, around 1-5 micrometers. When preparing abrasive paste, diamond micropowder is thoroughly mixed with specially refined oily carriers. Additives with lubricating, dispersing, and rust-preventing functions are added, and through processes like stirring and grinding, a uniform and fine paste is produced.
   • (2) Usage and Effects: When using abrasive paste, it is evenly applied to the surface of the grinding tool (such as a grinding disc or grinding rod), and then the workpiece is ground. Under the action of the grinding force, the diamond micropowder in the abrasive paste micro-cuts and polishes the workpiece surface, effectively removing tiny scratches, oxide layers, and other defects, making the workpiece surface achieve extremely high smoothness. Abrasive paste is suitable for manual grinding and mechanical grinding of small, precision parts, with flexible operation allowing for fine processing of local areas on the workpiece.

II. Application Examples in Automotive Parts Manufacturing

1. 1. Engine Block Grinding
   • (1) Processing Requirements and Difficulties: The engine block is a key component of an automobile engine, and its internal cylinder bores require extremely high Size accuracy and surface quality. The diameter tolerance of the cylinder bore is usually required to be controlled within ±0.03 millimeters, the roundness error is less than 0.005 millimeters, and the surface roughness needs to reach Ra0.2-0.4 micrometers. Because engine blocks are generally made of materials such as aluminum alloy or cast iron, which are relatively hard and have a large machining allowance, traditional grinding methods find it difficult to meet such stringent processing requirements.
   • (2) Application of Diamond Grinding Wheels: In the grinding process of engine blocks, diamond grinding wheels with ceramic binders are used. This type of grinding wheel has high hardness and wear resistance and can maintain stable cutting performance during high-speed grinding. When grinding cylinder bores, the linear velocity of the grinding wheel is usually controlled at 30-50 meters/second. By precisely controlling grinding parameters such as grinding depth and feed rate, excess material on the cylinder bore surface can be efficiently removed, ensuring the Size accuracy and roundness of the cylinder bore. After grinding with a diamond grinding wheel, the cylinder bore has low surface roughness, which can effectively reduce friction between the piston and the cylinder wall, improving engine fuel economy and power output stability.
2. 2. Crankshaft Grinding
   • (1) Importance of Crankshafts and Machining Accuracy: The crankshaft is the core component for power transmission in the engine, and its machining accuracy directly affects engine performance and reliability. The Size accuracy requirements for the main journals and connecting rod journals of the crankshaft are extremely high, with diameter tolerances generally within ±0.01 millimeters, cylindrical error less than 0.002 millimeters, and surface roughness reaching Ra0.1-0.2 micrometers. At the same time, the crankshaft has a complex shape, and the positional accuracy requirements between the various journals are also very strict.
   • (2) Advantages of Diamond Grinding WheelsIn crankshaft grinding, diamond grinding wheels with a resin bond are used. These wheels have good flexibility and self-sharpening properties, allowing them to automatically adjust the cutting edge during grinding according to the processing conditions, ensuring uniform and stable grinding. When grinding the crankshaft journals, a multi-axis CNC grinding machine is used in conjunction with a diamond grinding wheel to precisely control the grinding trajectory and achieve high-precision grinding of the crankshaft journals. Through processing with a diamond grinding wheel, the residual stress on the crankshaft surface is small, and the hardness is uniform, improving the fatigue strength and service life of the crankshaft, thereby improving the overall performance and reliability of the automobile engine.