CNC can directly process aluminum to achieve high -gloss mirror effect?
At present, CNC high gloss machining processes (milling and turning) are not well known by technicians in most industrial industries. Practical work shows that they are really mastered by only a few manufacturing enterprises.The main reason is that the demand is not very strong in the past, which is also closely related to cognition.Today, we are lucky to learn about it. First, let’s take a look at the picture of shell after CNC milling processing.
In recent years, with the development of high-performance and high-precision CNC machine tools and the emergence of high-performance metal cutting tools, CNC high finish machining has made a great breakthrough. It is possible to replace grinding with milling (turning), which has become the goal of the machining industry.The principle of CNC high gloss machining is to use special special tools on precision CNC machining equipment, and cooperate with scientific and reasonable cutting parameters and processes to achieve shiny machining surface effect.
Machine tool
The use of precision CNC machine tools is the prerequisite for high gloss machining.The machine tool should have good rigidity and precision, such as precision CNC engraving machine (general speed: 20000 rpm).The highlight effect of the tool is due to the use of a diamond tool.PCD Diamond milling cutter is the standard configuration of CNC high gloss machining industry.The edge of a good diamond tool can not see any rough edge of the notch under a high-power microscope.The cutting edge can withstand long-term cutting without change.The friction coefficient between diamond and nonferrous metals is very small, so the chips are not easy to stick to the blade, and there is no chip build-up. Therefore, the blade is always kept cutting the workpiece directly during the processing, and the brightness can be guaranteed.
The edge of the high gloss milling tool is wide, and the small rake angle or negative rake angle and the edge inclination angle close to zero are used. When the high gloss milling process is performed, on the one hand, the tool performs high-speed cutting, and on the other hand, because the rake angle of the tool is very small, the edge of the tool has a scraping and extrusion effect on the surface to be machined, which makes the workpiece surface obtain a very high finish and produce a hardening layer,The surface hardness and wear resistance of the workpiece are improved.
In addition to the geometric shape of the workpiece, the geometric shape of the tool mainly depends on the physical characteristics of the workpiece material.When processing plastic materials such as copper, aluminum and nickel, the front angle of the tool is 0 º, and the rear angle is generally between 5 º and 10 º.The radius of the tool tip arc is usually 0.5~5mm. For high machine tool rigidity, a larger radius can be used to reduce the surface roughness of the workpiece. If a smaller tool tip radius is used, the feed rate must be reduced accordingly in order not to deteriorate the surface roughness.When machining porous materials such as silicon, germanium, CaF2 and ZnS, the front angle of the tool is generally – 15 º~- 45 º.The optimum front angle depends not only on the material itself, but also on the rigidity of the machine tool and clamping system, which is best determined through production tests.
Disc milling cutter shall be used for high finish milling. The diameter of the cutter head shall be as large as possible according to the size of the plane to be milled, with good rigidity and good positioning accuracy of the blade.The size of the cutter head will change the pattern and effect of the milled plane. The number of blades can be single or multiple, but it is difficult and time-consuming to adjust the consistency of each blade with multiple blades. Single tool milling has a better effect.Diamond tools look expensive and require a large investment at a time, but natural diamonds are extremely hard and wear-resistant.According to statistics, the life of diamond turning tools is 25 times that of high-speed steel turning tools, and each diamond tool can be reground 6~15 times.Therefore, the tool consumption of each part is minimal, and stable size and high brightness can be obtained.The materials suitable for high gloss machining of workpiece include aluminum, copper, stainless steel, etc.When processing aluminum, its brightness is the brightest, and the tool wear is the smallest;When machining copper, its brightness is relatively bright, and the tool wear is next.When processing stainless steel, its brightness is Gray matte, and the tool wear is also large.
Technology
The cutting speed of mirror milling is usually about 30m/s.In order to process a perfect workpiece, the spindle must be dynamically balanced after tool change to minimize the ripple on the workpiece surface caused by dynamic imbalance.Diamond tools have good heat conduction performance and small cutting amount, so it is unnecessary to add coolant.On the contrary, the addition of coolant not only increases the trouble of cleaning after processing, but also makes the coolant mixed with iron filings often become the cause of blade collapse.The defect of highlight is that the contour of the product is required to be high and stable, otherwise the highlight will be uneven (big and small edges, etc.).In order to obtain safety technical data including all relevant information (such as tools, materials and processing technology) and make it an optimal combination, it often requires an experience exploration and running in process.
But for some processing plants with limited budget costs, PCD diamond tools may be more expensive.Is there a carbide milling cutter that can achieve aluminum mirror effect?In fact, as long as it is properly used, it is possible to achieve this effect:
1) Select high-quality fine material and sharp milling cutter;
2) Adopt “stable, slow, precise and fine” knife feeding method;
3) Assisted by spraying lubricating oil and coolant;
4) High speed flying milling;
The mirror effect can be achieved.
The special carbide milling cutter of SZSUNLIT STC310H series has achieved the best mirror effect of aluminum processing at the lowest cost. Please see the following video of the effect produced by the special aluminum alloy milling cutter walking cutter program of D10. Refer to the processing parameters 10000 rpm, 1200 feed, 20 side cutting depth, and allowance AE0.1.
