For example, when processing aluminum heat sinks on a horizontal CNC machining center, multi-station finishing is generally required, so the best position of the parts (including fixtures) on the machine tool table must be considered. It should be determined by considering the machine parameters during the technical preparation process and optimizing and matching the tool length of each part. If you do not consider the overtravel of the machine tool and change the tool, it will affect the machining accuracy or re-enter the trial cutting stage. In this case, more time will be wasted. At the same time, it also increases the possibility of waste products, so this issue must be considered before CNC machining of aluminum heat sinks.
If the CNC machining machine has an automatic tool change function, it is determined that its biggest weakness is the tool cantilever machining, and the boring die and bracket cannot be used during the machining process. When processing multi-station parts, we need to accurately calculate the distance from each machining surface of each station to the end face of the machine tool spindle and select the best tool length. After setting, the necessary inspections should be carried out when the first aluminum heat sink is formed.
In addition, CNC machining of aluminum heat sinks should pay attention to the following issues:
(1) If the aluminum heat sink is too high, especially when processing some high-power heat sinks, you should use milling cutters of different lengths to roughen it in layers. After roughing with a large milling tool, it should be finished with a small milling tool.
(2) Flat-bottom milling cutters are used to process planes, and ball cutters are used less in order to reduce processing time;
If there is a slope and it is an integer, the slope milling cutter is used for machining.
(3) Reasonable setting of tolerances makes the machining accuracy and computer calculation time balance each other. Do more procedures to reduce the time of empty knife.
(4) If the material hardness of the aluminum heat sink of the profile is high, choose up-cut milling;
The material hardness of the aluminum heat sink is low, so choose down milling. In addition, up-milling is used for roughing, and down-milling is used for finishing.
(5) The tool material has good toughness and low hardness, suitable for rough machining. The tool material has poor toughness and high hardness, which is suitable for finishing.
(6) Be careful not to touch the profile aluminum heat sink tooth fins during processing, so as not to damage the tooth fins. In particular, if some heat sinks have been anodes and then processed, special attention is required.
The above problems are all the points that should be paid attention to in CNC machining of aluminum heat sinks. Skilled technicians generally notice these problems. If they are novices or employees who are new to heat sink processing, they need more guidance.
