In the frontier of modern manufacturing, micro-precision parts processing is playing an increasingly critical role. From tiny instruments used for precise diagnosis and treatment in medical equipment to fine components that determine the performance of electronic equipment, micro-precision parts are everywhere. However, while this field is booming, it is also facing many technical bottlenecks that limit its further breakthroughs.

The ultimate challenge of machining accuracy

In the field of micro-precision parts processing, the precision requirements are demanding. Taking medical parts processing as an example, the dimensional accuracy of some instrument parts used in minimally invasive surgery needs to be controlled at the micron or even nanometer level. In the process of CNC precision machining, it is not easy to achieve such high precision. Factors such as slight vibration of machine tools, wear of tools, and thermal deformation will have a significant impact on machining accuracy. Even advanced five-axis CNC machining equipment will find it difficult to achieve ideal accuracy when facing extremely small parts processing due to the inherent errors of the mechanical structure. For example, when machining micro-shaft parts with a diameter of only 0.1 mm, slight wear of the tool cutting edge may cause the part size deviation to exceed the allowable range, seriously affecting the matching accuracy and performance of the parts.

Material properties and processing adaptation problems

The processing of micro-precision parts is extremely picky about the selection of materials. On the one hand, the material needs to have good mechanical properties, such as high strength and high hardness, to meet the functional requirements of the parts in actual use; on the other hand, the material must also have excellent processing performance to facilitate precision processing. However, it is often difficult to take both into account. Some high-strength alloy materials, although they perform well in performance, are very prone to cracks, deformation and other problems during precision machining. Take titanium alloy as an example. It is widely used in the medical field, but due to its high chemical activity and poor thermal conductivity, the tool is easy to wear during cutting, and the surface quality of the machining is difficult to guarantee. In addition, for some ultra-micro parts, the microstructure of the material has a more significant impact on the machining accuracy and surface quality. How to select suitable materials and optimize the processing technology to adapt to the material characteristics has become a major technical bottleneck.

Limitations of equipment and technology

• Equipment accuracy and stability: Micro-precision parts processing relies on high-precision processing equipment. Although modern processing equipment continues to develop in the direction of high precision and high stability, it is still unable to cope with micro-scale processing tasks. For example, the positioning accuracy and repeatability of ordinary CNC machine tools can meet the requirements when processing larger parts, but when processing micro-precision parts, the precision errors of key components such as the lead screw and guide rail of the machine tool will be magnified, resulting in the inability to meet the processing accuracy requirements. Moreover, the stability changes caused by factors such as heat and vibration during the long-term operation of the equipment will also have an adverse effect on the processing accuracy.
• Complexity of processing technology: The complex shapes and high-precision requirements of micro-precision parts make traditional processing technology difficult to handle. Although new processing technologies continue to emerge, there are still many problems in practical applications. For example, when using EDM to process micro-precision parts, although complex shapes can be processed, a metamorphic layer will be formed on the surface of the parts during the processing, affecting the surface quality and fatigue performance of the parts. In addition, for some ultra-precision surface processing, such as ultra-precision grinding of optical lenses, the current processing technology is inefficient and costly, making it difficult to achieve large-scale production.

Dilemma of detection and quality control

After the processing of micro-precision parts is completed, it is also difficult to accurately detect and control their quality. Conventional detection methods, such as calipers and micrometers, cannot meet the high-precision measurement needs of micro parts. Advanced detection equipment, such as atomic force microscopes and scanning electron microscopes, can achieve nanometer-level measurement accuracy, but the equipment is expensive, complicated to operate, and has low detection efficiency. In the processing of medical parts, how to quickly and accurately detect the dimensional accuracy, shape accuracy, and surface quality of mass-produced micro parts has become a key issue to ensure product quality and production efficiency. At the same time, due to the small size of micro parts, the damage of the detection equipment to the parts must also be considered during the detection process, which further increases the difficulty of detection and quality control.

Micro precision parts processing faces many technical bottlenecks in terms of accuracy improvement, material adaptation, equipment process optimization, and detection control. Only by continuously breaking through these bottlenecks can the micro precision parts processing technology be promoted to a higher level and meet the growing demand for micro precision parts in various fields.