At home and abroad, micro holes are defined as those with a diameter of 0.1-1.0RAM and those with a diameter less than 01.mm are called micro holes. The development trend of the application of the filter screen used by the fuel nozzle of internal combustion engine is roughly the same, so the requirements for the punch processing of small holes are increasingly high.

 

Technical problems and solutions of micro-hole metal stamping processing

 

At home and abroad at present, the small hole is defined as: 0.1 1.0 ram diameter hole called holes, the diameter is less than. 01 mm holes called pores, with the emerging of the microelectronics industry, the rapid development of micro mechanical and mems industry, with micro hole is the key structure components of the use of more and more, the aperture size smaller and smaller, the accuracy is higher and higher. Such as aeroengine turbine blade cooling hole, jewel bearing hole, electron microscope grating and MPP, polymer composite materials for PCB hole, diamond die, precision chemical fiber spinneret, RP technology of rapid prototyping equipment, fiber optic connectors, fuel injection nozzle, nozzle hole printer ink jet hole, red blood cell filter and micro spray, micro pump, micro-structure of high-end products, etc. The workpiece materials of these products are mostly metal alloy materials, with fine hole with large depth-width ratio and characteristic size between 50 and 100pm.

Microhole metal stamping

For micro hole machining, due to the workpiece material toward the direction of high strength, high hardness, many parts need to use a heat resistant steel, stainless steel, die steel, cemented carbide, ceramics, diamond and other polymer composite materials and other difficult processing materials, in addition, the shape of a tiny hole is no longer a single round, but tend to various can realize specific functions of complex shapes, such as trilobites in the spinneret circular arc form, 3 leaf edge shape, v, hexagonal and other special-shaped hole, hole for all the minor updated processing technology put forward higher requirements. Specifically, miniaturization industrial processing technology should satisfy mass, high efficiency, high precision, high density, short cycle, low cost, pollution-free, net shaping characteristics, and in the field of traditional macro manufacturing, plastic forming process (cutting, bending, drawing, deep drawing, superplastic extrusion, rolling, embossing, etc.) with the industry advantages. Microstamping is the key process method in microplastic forming technology. This paper studies the microstamping process from the aspect of the development of processing equipment, aiming at the processing of microholes.

Microhole metal stamping

In the manufacturing industry, the diameter of the micro hole processing bit is generally = more than 0.27, the tool material is imported from Japan tungsten steel or white steel, in the past due to the etching processing cost is high, laser precision is poor, with the improvement of the metal hole stamping process, has been basically eliminated. Stable implementation of mass production. With the increase of mobile phone functions, the circuit distribution of printed circuit board is increasingly developing towards the direction of density, the copper foil on the circuit board microhole diameter is smaller, and the processing difficulty is further increased. The application trend of the filter screen used by the fuel nozzle of internal combustion engine is similar, so the requirement of the punch processing is higher and higher.

Microhole metal stamping

There are many reasons why punching needle breaks easily, which may be the reason of punching itself or the design defect of mould. Also be cutting materials and so on a series of problems in whatever it is, we should to resolve solution practice GeChang same, foreign precision mould generally is loose, and stripper is very tight, stripper and die must be set guide pin, guide sleeve, line cutting cutting with wire walking or using oil, male splint bilateral 0.02 ~ 0.06 mm, 0.01 mm stripper bilateral even fitting. Domestic practice is a little different, general common splint unilateral tolerance ±5, stripper unilateral 0.01mm,; When using slow walk silk, can consider to increase appropriately some. Punching needle offset, to try to make the punching needle shorter, the clearance should be put appropriately, the guide post should be larger, and the clearance with the guide sleeve of the die should not exceed 0.005mm on one side. The gap of stripper plate is smaller than that of the lower template. Generally, take bilateral 0.005mm and bilateral 0.02mm of the common splint. There is nothing to do with the loose point.