With the improvement of people’s living standards, people increasingly like things with metallic texture, which also makes aluminum products more and more used in many industries. Compared with steel and superalloys, it is a soft metal, and the hardness of HRC is not high, but it is more tough. Therefore, the relative requirements of the tool are relatively higher. If the soft metal is cut with a high-hardness tungsten steel milling cutter, the cutting edge will be broken, and the tool life will be very short. It requires high-quality tools with low hardness and no sticking to the knife to complete the processing. The only way the knife can increase the machine’s speed and efficiency can be.
How To Choose Machining Blades For CNC Aluminum Parts?
When machining aluminum alloys, especially in the finishing of small margin cutting, the cutting edge of indexable inserts is usually blunt, which often leads to the “ploughing” effect, and the cutting edge is also easy to cut into the workpiece suddenly, causing a sudden increase in cutting force . The sudden increase in cutting force leads to excessive tool size and high power requirements. The above-mentioned problems are more complicated due to the demand for cutting edges. A sharp positive cutting edge must be used for finishing. In order to ensure the metal removal rate during roughing, the cutting edge is required to have sufficient strength. Therefore, consider cutting force, cutting edge penetration, chip formation, stability, and insert positioning and clamping.
The ultimate goal of machining is to produce the best parts that meet the design or customer specific requirements. Specifications can be in the form of part thickness, load-bearing capacity and size. CNC machine tools can handle aluminum parts of various sizes and shapes through effective tool sequencing and manipulation. Increasing output requires the use of indexable cutting tools. This type of tool allows the operator to change the tool blade when necessary, allowing multiple automatic machining of aluminum parts. CNC tool inserts with different cutting edges can be used for post-processing operations, such as polishing and grinding aluminum parts. In the machining environment of CNC aluminum parts, the performance of the tool blade depends on the shape of the blade, the relief angle and the rake angle.
Tools for CNC aluminum parts have specific geometries that affect the quality of the final product. The blades have different shapes to fit specific CNC tool holders. Aluminum tool blades are available in rhombus, circle, triangle and square shapes. The use of sharp-angled blades can achieve better part quality. For example, for high-speed surface processing of forged aluminum parts, it is best to use 30 o -35o blades. Turning forged aluminum with diamond blades will result in a high-quality surface finish.
On the other hand, CNC machining of cast aluminum parts will require operators to use circular inserts to improve quality. The surface of cast aluminum is rough. Processing with sharp tools will result in poor surface finish. The shape of the tool insert affects CNC parameters such as feed rate, depth of cut and tool clearance. Sharper shapes will require smaller feed rates and larger tool clearances.
For machining tools, what factors do we need to consider?
Rake Angle And Approach Angle
The rake angle refers to the angle between the tip of the cutting tool relative to the clamped workpiece on the CNC machine tool. The angle can be positive or negative depending on the position of the tool insert. We prefer to process aluminum parts with positive rake angles. Since it is a soft metal, we must minimize cutting resistance throughout the production process.
During the machining process, because the chips accumulate around the tool, it will affect the final quality of the product. The positive rake angle ensures effective chip handling. By reducing the cutting temperature, it also contributes to temperature control. This factor helps to provide the best processing conditions for aluminum parts and extend the life of the blade.
CNC milling rarely relies on the rake angle. This is because the approach angle defines the relationship between the part and the position of the tool on the CNC tool post. Due to the machinability of aluminum, we use a 90-degree timing. It allows our experts to perform different milling processes. These include face milling, slot milling and shoulder milling.
Factor Of Diameter
For the influence of radial cutting force, small to medium-diameter tools have poor rigidity and are more prone to deflection, while large-diameter tools are more stable, and they have different requirements for anti-vibration. In addition, it is also found that the feed rate is not the main factor affecting the radial cutting force. Between the different feeds of the tool (usually the feed per tooth is 0.25mm and 0.35mm), the radial cutting force is only slightly Variety. For a typical aluminum alloy milling cutter with a diameter of 25mm, the edge band on the blade is 1°, 0.1mm wide, and is perfectly matched with the curved cutting edge.
This parameter also defines the relationship between the tool and the clamped workpiece on the CNC machine tool. In this parameter, the tool insertion is the reference point. Like the rake angle, it can be positive or negative.
When processing CNC aluminum parts, whether it is rapid prototyping or mass production, a positive clearance angle is recommended. The use of indexable blades allows the operator to change the back angle. The release angle is between 20o and 30o, which can provide better surface finish for aluminum parts.
Aluminum Chip Breakers
The accumulation of chips will hinder the high-speed machining of aluminum parts. Generally, chips are sticky in nature, which can present challenges when managing the machining space on the CNC surface. The chip breaker design used in CNC machine tools depends largely on the rake and relief angles.
In the mass production of CNC aluminum parts, it is recommended to use sharp and wide chipbreakers. The wider chip breaker can remove chips of various sizes.
If you are looking for the ideal CNC aluminum parts processing service, just contact us.