The hottest micro mold micro milling brings new op

2022-09-21
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Micro mold and micro milling bring new opportunities

if there is any hint from iPod, the smaller the better. IPod has become one of the most popular gadgets to successfully occupy the market, bringing apple a lot of profits and pushing the stock price to a new high. Not only was the shape of the iPod small at first, but it was making it smaller. Now the smaller iPod Nano model replaces the iPod mini model; And then there are very small iPod models. IPod is not the only one getting smaller. Computers and televisions are also becoming thinner. The amount of subsidy is 80% of the annual insurance premium. The progress of medical equipment makes more and more micro devices can be installed into our bodies; Even a tiny camera can travel through the body. Not only are things getting smaller, they are equipped with more parts, which can provide additional power and functions for FM operation. Micro parts are widely used in aviation, automobile, biomedicine, electronics, information technology, optics, telecommunications and other industries. The development of all these products is putting forward higher requirements for small parts and products. In order to continuously reduce costs, most of these small parts are produced with molds. These trends pose a variety of new challenges to mold manufacturers, ranging from the use of new space age materials to special mold coatings, milling parts with 0.1mm diameter tools and achieving sub micron accuracy. At the same time, the inherent complexity of micro parts also brings new opportunities for mold manufacturers. Whenever simple and moderately complex mold manufacturing is transferred to countries with low labor costs, mold manufacturers in the United States and Europe can turn to more advanced technologies such as micro mold and micro milling to maintain their competitive advantage

processing of small parts

one of the main challenges of mold processing for small parts is the processing of micro parts. Both the direct milling of the effective area of the die and the manufacturing of small EDM electrodes put forward high requirements for the milling process. Challenges related to micro milling include the use of micro tools with diameters reduced to 100 microns (m) or less and operating at very high speeds up to 150000 R/min. The surface quality (RA) needs to reach 0.2 M. And since polishing is unrealistic for such small parts and tiny details, micro milling requires a processing without polishing

micro milling technology

in order to obtain the quality and accuracy required by micro milling and meet the economic constraints, the whole manufacturing chain must be optimized and synchronized. Suppliers of CNC machine tools, cutting tools, tool handles, fixtures and quality control equipment need to provide correct solutions at competitive costs. The following is a list of main problems that should be raised in the micro milling environment:

small size tools are the implementers of micro milling. Depending on the size of the workpiece, they can be as small as 0.1mm and may become smaller in the future. When entrusting a micro milling project, the availability and cost of tools must be considered. When using small-diameter tools, high-speed spindle is very important. Using a tool with a diameter of 0.1mm at 10000r/min of the spindle means that the cutting speed (VC) is only 3.3 m/min, which is too low! For the spindle with the speed level of 20, 000, it is necessary to combine the spindle with the thermal expansion tool handle for complete dynamic balance and zero runout. Otherwise, the surface quality will be damaged and the tool life will be significantly shortened. In most cases, the production of micro milling parts should be completed in one clamping. For example, the combination of EDM and milling is likely to cause unacceptable misalignment and tool marks. Needless to say, the machine tool must have good consistency of accuracy and be able to distinguish four decimal places (size sensor). Micro milling can make good use of the function of five axis milling. The ability to tilt the tool away from the material allows it to use shorter tools. However, since the current accuracy of five axis linkage milling is worse than that of three axis milling, when the five axis linkage is used for micro milling, the specification and actual performance of the machine tool must be carefully verified. The machine environment must have controllable temperature (software compensation may not be enough) and avoid vibration. If the machine tool is not properly isolated, even if a heavy truck passes outside the plant, the possible vibration is enough to leave traces on the surface of the workpiece. Depending on the geometry of the part, micro milling may require a special machining strategy that goes beyond simple scaling down. For example, in many cases, reverse milling (and non forward milling) will be the preferred milling strategy

cad/cam solution for high-precision micro milling for mold manufacturing, with a complete set of easy-to-use 3-D tools

requirements of cad/cam system

everyone intuitively believes that milling machines, tool shanks and tools are difficult to scale down to the very small size and extremely high accuracy required for micro milling. At first glance, software seems to be easier to match. After all, someone has to say that dealing with numbers like 0.0001 should be as easy for software as dealing with 1.0 or 10. But it is more complex than what is presented in front of us. Generating and modifying geometric shapes with correct accuracy, smoothness and continuity is only an entry point for CAD solutions for small components. In order to get a functional solution suitable for micro milling, the CAD system must be carefully adjusted and optimized to support the following requirements:

read the part model reliably and accurately. Minimizing the need for multiple data transformations is critical to maintaining the accuracy of detailed models

when generating parting surfaces or creating geometric shapes for sliders, pushers, and ejector rods, very tight 0 The shape and position tolerance of 01 microns is effective. This is necessary to prevent the gap between the parting surfaces and maintain the continuity of C1 and C2

handle multi cavity molds with very small specifications, including special sample parts and components

cam system must also be optimized for micro milling. NC software must deal with tight tolerance and ultra-high precision machining. And since the operator cannot intervene to prevent the damage of the tool, the NC software must accurately consider the chip load throughout the machining process. In order to fully support micro milling, CAM software should be able to:

accurately use a very detailed mathematical model to maintain its complexity. Having an integrated cad/cam solution is ideal because it eliminates any data conversion in processing

the CAD system includes high-precision and built-in CAD capabilities to provide modeling assistance with appropriate accuracy and tangency in the cam system (for example, capping, extension, etc.)

support tool path calculation with deviation as low as 0.1 M. This is particularly challenging when machining micro features on large parts

support the calculation of micro milling level parameters when considering the constraints of actual machine tools. For example, a cam system may require a tool with a diameter of 0.1mm, a step distance of 0.005mm, and a 10 times larger arc radius of the 0.05mm tool tip to provide ultra precision results. The generated tool path must be accurate to five decimal places

support machining strategies optimized for micro milling, such as rough machining, semi finishing and finishing with the same NC operation

in order to reduce the machining time and protect the precision tool from damage, the knowledge of adjusting the feed rate according to the actual machining allowance to control the actual tool load is used in the whole machining process

summary: micro system, micro mold and micro milling are novel and exciting technologies for mass production of micro parts. With sub micron accuracy and tool tips that are almost invisible to the naked eye, this emerging and rapidly growing field poses many challenges to mold manufacturers and suppliers. New materials, new tools, special mold coatings and innovative cad/cam software technology must be studied and mastered. On the bright side, micro systems and micro milling bring new opportunities to mold 980.7 manufacturers who are looking for differences, get more business and are in a better position than low wage competitors. The effective development of this field requires cooperation between industries, research institutions and governments. Such cooperation is already under way in Europe. The European Union's technical cooperation research action (craft) project brings together the Fraunhofer Institute of production technology (IPT) and leading suppliers of cad/cam, CNC machine tools, cutting tools and fixtures to develop next-generation materials, machine tools and software tools and work methodologies for micro manufacturing. It is time for the North American tool industry to join in the development of this emerging and attractive and profitable segment

introduction to micro milling

micro system technology has become one of the fastest-growing industries in the world. Industries that need to manufacture extremely small high-precision parts, such as bio medical equipment, optics, and Microelectronics (including mobile communications and computer components), have a large demand. For parts requiring micro system processing, the accuracy is as high as 5mm or less, the surface quality is 0.2mm or less, and the hardness of parts also reaches 45 HRC or higher. Micro milling is a new processing technology for machining micro parts and high-precision parts. Micro milling uses very small tools (diameter less than 0.1mm) and can obtain very small surface tolerance and high-quality surface accuracy, which can not be achieved by general NC software. Therefore, manufacturers have to face the following great challenges: part deformation, increased complexity, the need to process workpieces with micro features with extremely high accuracy, and the use of micron level special tools. For example, for a workpiece with a diameter of 0.1mm, in order to obtain a surface with high accuracy requirements and meet the above requirements, the micro milling technology needs to meet the following support: a small diameter tool of 100mm or less; High speed tools with a profile ratio (l/d) of 10 or up to 100; 150000 r/min or higher spindle speed; Machining tolerance of 0.1mm or less; Ability to correct geometry. Micro milling is the future of high-speed milling, and companies proficient in micro precision tooling will have greater competitiveness

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