What milling cutter should be used for machining aluminum alloy?

Currently, machined aluminum parts are mainly categorized into two major types: wrought aluminum alloys and cast aluminum alloys. So, what kind of milling cutter should be used for machining aluminum alloys? Is it better to use a dedicated aluminum-machining end mill or other specialized tools for aluminum alloys in order to achieve higher machining efficiency? This article discusses the optimal milling cutter for aluminum alloy machining from several aspects: the characteristics of aluminum alloy milling, the selection of cutting tools, and the choice of cutting parameters. I. Characteristics of Aluminum Alloy Machining Milling aluminum alloys has the following key characteristics: 1. Low Hardness of Aluminum Alloys Compared with titanium alloys and other quenched steels, aluminum alloys have relatively low hardness; however, heat-treated or die-cast aluminum alloys can exhibit much higher hardness. The typical HRC hardness of ordinary aluminum sheets is generally below 40. Consequently, when machining aluminum alloys, the cutting tool experiences a lighter load. Moreover, due to aluminum’s excellent thermal conductivity, the cutting temperature during milling is relatively low, allowing for higher cutting speeds. 2. Low Plasticity of Aluminum Alloys Aluminum alloys have low plasticity and a low melting point. During machining, they tend to adhere to the cutting tool, chip evacuation is poor, and surface roughness tends to be high. In fact, the main challenges in machining aluminum alloys are tool sticking and poor surface finish. As long as these two issues—tool sticking and surface quality—are effectively addressed, most problems associated with aluminum alloy machining can be readily solved. 3. Rapid Tool Wear If an inappropriate tool material is selected, machining aluminum alloys often leads to accelerated tool wear due to issues such as tool sticking and poor chip evacuation. II. What Kind of Milling Cutter Should Be Used for Machining Aluminum Alloys? For general aluminum alloy machining, a three-flute aluminum-specific end mill is typically used. Depending on the specific machining conditions, a two-flute ball-nose end mill or a four-flute flat-bottom end mill may also be employed. However, Nanjing Jianchuanshi recommends that, in most cases, a three-flute flat-bottom end mill is the best choice. 1. Selection of Tungsten Carbide End Mills for Aluminum The number of flutes is usually three, and the material is typically YG-class cemented carbide, which helps reduce the chemical affinity between the tool and the aluminum alloy. Many CNC tool manufacturers offer dedicated series of end mills for aluminum alloy machining, such as the US200 series from Jinlu and the AL series from Swiss Fraisa. 2. High-Speed Steel Tools High-speed steel end mills for aluminum are sharper and can also perform well in machining aluminum alloys. III. Cutting Parameters for Milling Aluminum Alloys When machining ordinary aluminum alloys, high-speed, high-feed milling is generally recommended. Additionally, a larger rake angle should be chosen whenever possible to increase chip space and reduce tool sticking. For finishing operations on aluminum alloys, water-based cutting fluids should be avoided to prevent the formation of tiny pinholes on the machined surface; instead, kerosene or diesel oil is typically used as the cutting fluid for aluminum sheet machining. The cutting speed for aluminum alloy milling tools varies depending on the tool material, tool parameters, and machining process. Specific cutting parameters should be determined based on the manufacturer’s recommendations.

Release time:

2022-06-25

Currently, machined aluminum parts are mainly categorized into two major types: wrought aluminum alloys and cast aluminum alloys. So, what kind of milling cutter should be used for machining aluminum alloys? Is it more efficient to use a milling cutter or cutting tool specifically designed for aluminum alloys? This article discusses the optimal milling cutter for machining aluminum alloys from several perspectives: the milling characteristics of aluminum alloys, the selection of cutting tools, and cutting parameters.

I. Machining Characteristics of Aluminum Alloys

Milling aluminum alloys has the following major characteristics:

1. Low hardness of aluminum alloy

Compared with titanium alloys and other quenched steels, aluminum alloys have lower hardness; however, heat-treated or die-cast aluminum alloys can achieve much higher hardness. The HRC hardness of ordinary aluminum sheets typically remains below 40. Consequently, when machining aluminum alloys, the cutting tool experiences relatively low cutting loads. Moreover, due to aluminum’s excellent thermal conductivity, the cutting temperature during milling is comparatively low, allowing for higher milling speeds.

2. Aluminum alloys have low ductility.

Aluminum alloys exhibit low ductility and a relatively low melting point. During machining, they are prone to severe built-up edge formation, poor chip evacuation, and high surface roughness. In essence, the primary challenges in machining aluminum alloys boil down to built-up edge and poor surface finish. As long as these two major issues—built-up edge and surface quality—are effectively addressed, the difficulties associated with machining aluminum alloys will be readily overcome.

3. Cutting tools are prone to wear.

When machining aluminum alloys with unsuitable cutting-tool materials, issues such as built-up edge and poor chip evacuation often lead to accelerated tool wear.

II. What milling cutter should be used for machining aluminum alloys?

For machining aluminum alloys, a three-flute aluminum milling cutter is typically used; however, depending on the specific machining conditions, a two-flute ball-end mill or a four-flute flat-bottom end mill may also be employed. That said, Nanjing Jianchuanshi recommends that, in most cases, a three-flute flat-bottom end mill is the optimal choice.

1. Selection of Tungsten Carbide Milling Cutters for Aluminum

Cutting tools typically have three cutting edges, and YG-class cemented carbide is generally selected as the material to minimize chemical affinity between the tool and aluminum alloys. Most CNC tool manufacturers offer dedicated milling cutter series for machining aluminum alloys, such as the US200 series from Jinlu and the AL series from Swiss Fraisa.

2. High-speed steel material

High-speed steel end mills for aluminum are quite sharp and can also machine aluminum alloys very effectively.

III. Cutting Parameters for Milling Aluminum Alloys

For machining common aluminum alloys, high-speed, high-feed milling is generally the preferred method. In addition, whenever possible, a larger rake angle should be selected to increase chip evacuation space and reduce built-up edge formation. For finish machining of aluminum alloys, water-based cutting fluids should be avoided to prevent the formation of tiny pinholes on the machined surface; kerosene or diesel oil is typically used as the cutting fluid for machining aluminum sheets.

The cutting speed for machining aluminum alloy end mills varies depending on the mill’s material and parameters, as well as the specific machining process employed. Specific cutting parameters should be determined based on the manufacturer’s recommended values.