In modern high-end manufacturing, the precision requirements for high-precision mechanical parts have reached an almost demanding level. Diamond micropowder, with its superior physical properties, has become an indispensable key material in the field of ultra-precision machining, playing a core role in the manufacturing process of important components such as aero-engine turbine blades and precision molds.

I. Aero-engine Turbine Blade Machining

1. 1. Importance and Machining Challenges of Turbine Blades
   • (1) The turbine blades of an aero-engine are one of the core components of the engine, and their working environment is extremely harsh. During engine operation, the turbine blades must withstand high temperatures of over 1500℃, high-speed rotation of tens of thousands of revolutions per minute, and enormous centrifugal forces and complex airflow impacts. Therefore, extremely high requirements are placed on the material properties, structural design, and machining precision of the turbine blades. Any minor machining defects may cause fatigue cracks, deformation, or even fracture of the blades during service, seriously affecting the safety and reliability of the engine.
   • (2) Turbine blades are usually manufactured using high-strength, high-temperature materials such as superalloys and single-crystal alloys. These materials have high hardness and are difficult to machine, and traditional machining methods cannot meet their high-precision machining requirements.
2. 2. Application of Diamond Micropowder in Turbine Blade Machining
   • (1) Rough Machining StageIn the initial machining stage of turbine blades, diamond micropowder with a relatively large particle size, generally between 20 and 50 microns, is used. After mixing it with a specially formulated grinding fluid, it is applied to grinding equipment. Through grinding, excess material on the surface of the blade blank can be quickly removed, and the approximate shape of the blade is initially formed. For example, when rough machining a turbine blade blank made of nickel-based superalloy, diamond micropowder grinding can control the dimensional error of the blade within ±0.1 mm while ensuring machining efficiency, laying the foundation for subsequent fine machining.
   • (2) Semi-finishing StageAs the machining progresses, the process enters the semi-finishing stage, at which time diamond micropowder with a particle size of 5-20 microns is used. The main task of this stage is to further improve the surface flatness and size accuracy of the blade and eliminate scratches and unevenness left by rough machining. By precisely controlling grinding parameters such as grinding pressure, speed, and time, the surface roughness of the blade can be reduced to 1-2 microns, and the surface accuracy of the blade can be improved to about ±0.05 mm, making the shape of the blade closer to the final design requirements.
   • (3) Ultra-precision Polishing StageIn the final stage of turbine blade machining, ultra-precision polishing is performed using diamond micropowder with an extremely fine particle size, typically between 0.1 and 1 micron. During polishing, the diamond micropowder is mixed with a specially formulated polishing fluid and evenly applied to the polishing tool. Under the action of high-precision polishing equipment, the micropowder performs atomic-level fine grinding on the blade surface, making the blade surface achieve nanometer-level smoothness. After polishing, the surface roughness of the blade can be reduced to less than 10 nanometers, and the surface accuracy can reach within ±0.01 mm.
3. 3. Improvement of Turbine Blade Performance
   • (1) Optimization of Aerodynamic PerformanceAfter ultra-precision machining with diamond micropowder, the surface of the turbine blade is extremely smooth, and the blade surface accuracy is extremely high, which can precisely control the flow of airflow on the blade surface. This reduces the resistance of the airflow when passing through the blade, making the flow more stable, thereby significantly improving the air compression ratio and turbine efficiency of the engine. For example, by ultra-precision machining of turbine blades, the fuel economy of the engine can be improved by 5%-10%, and the thrust can be increased by 3%-5%.
   • (2) Enhanced ReliabilityHigh-precision machining ensures the reliability of turbine blades under complex operating conditions. The smooth surface reduces stress concentration points, reducing the risk of fatigue cracks in the blades under high temperature and high-speed rotation. At the same time, precise surface accuracy ensures uniform stress on the blades during operation, extending the service life of the blades. According to statistics, the service life of ultra-precision machined turbine blades can be extended by 20%-30%, greatly improving the reliability and safety of aero-engines.

II. Precision Mold Machining

1. 1. Characteristics and Machining Requirements of Precision Molds
   • (1) Precision molds are widely used in electronics, automobiles, medical devices, and other industries to manufacture various high-precision components. Precision molds are characterized by complex structures and extremely high precision requirements. The size accuracy of their cavities and cores is usually required to be controlled within ±0.005 mm, and the surface roughness is required to reach Ra0.05-0.1 microns. The precision and surface quality of the mold directly affect the forming quality and production efficiency of plastic and metal products.
   • (2) Precision molds are usually made of materials such as mold steel and cemented carbide. These materials have high hardness and good wear resistance, but the machining difficulty is correspondingly increased.
2. 2. Role of Diamond Micropowder in Precision Mold Machining
   • (1) Grinding after Electrical Discharge MachiningIn the process of precision mold machining, electrical discharge machining is a commonly used forming method, but after electrical discharge machining, a layer of altered layer will be formed on the surface of the mold, and the surface roughness will be poor. At this time, using diamond micropowder with a particle size of 1-10 microns for grinding can effectively remove the altered layer left by electrical discharge machining and improve the surface quality of the mold. Through grinding, the surface roughness of the mold can be reduced from Ra1-2 microns after electrical discharge machining to Ra0.1-0.5 microns, while restoring the hardness and wear resistance of the mold surface.
   • (2) Polishing StageIn the final polishing stage of mold machining, diamond micropowder with a particle size of 0.05 - 0.5 microns is used. After mixing it with a special polishing paste, the mold surface is finely polished using polishing equipment. Diamond micropowder can perform extremely fine cutting on the microscopic protrusions of the mold surface, making the mold surface mirror-like. After polishing, the surface roughness of the mold can be reduced to below Ra0.05 microns, greatly improving the mold release performance and the surface quality of plastic and metal products. For example, when manufacturing injection molds for Mobile phone casings, the molds polished with diamond micropowder produce Mobile phone casings with mirror-smooth surfaces, free of flow marks and defects, greatly improving the product's appearance quality.
3. 3. Impact on the performance and production of precision molds
   • (1) Improve mold lifeMolds processed with diamond micropowder have high surface hardness and good wear resistance, able to withstand friction and wear during frequent stamping and injection molding processes. The service life of the mold can be extended by 30% - 50% compared to molds that have not undergone fine processing, reducing the number of mold replacements and lowering production costs.
   • (2) Improve product qualityHigh-precision molds ensure the molding precision and surface quality of plastic and metal products. The Size precision of the products can be strictly controlled, with high surface smoothness and few defects, improving the product's yield rate and market competitiveness. For example, in the manufacture of automotive parts, using molds that have undergone ultra-precision machining with diamond micropowder results in parts with higher Size precision, tighter assembly, and improved overall vehicle performance and quality.