Coated cutting tools are used in the CNC tools for the CNC machining group. The cutting tool's efficiency can be enhanced by adding a coating to it. The coated tools provide a major improvement in cutting efficiency. Coating one or more layers of the refractory compound with good wear resistance on the tool body with good durability, which significantly enhances the tool's efficiency by combining the tool matrix and hardness, is referred to as a coated cutting tool. Coated tools can help to increase machining performance, boost machining precision, extend tool life, and lower machining costs. Coated CNC tools make up about 80% of all cutting tools and will become a common option for a wide range of CNC tools.
Types of Coated Tools in CNC Machining
1. Coating tools for CNC machining are classified as chemical vapor deposition coating tools or physical vapor deposition coating tools based on their coating methods. The chemical vapor deposition method is commonly used to coat cemented carbide tools, with a deposition temperature of about 1000 °C. The physical vapor deposition method is normally used to coat high-speed steel equipment, and the deposition temperature is about 500 °C.
2. Cutting tool coating can be classified into carbide coated tools, high-speed steel coated tools, coating tools on ceramics, and superhard materials based on the various substrate materials of coated tools.
3. Coating tools are graded as "hard" or "soft" coating tools depending on the properties of the coating materials. The “hard” coating tool is used to achieve the high hardness and wear resistance, and its benefits include high hardness and strong wear resistance, which are common in tic and tin coating. The goal of a "soft" coating tool is to have a low friction coefficient, or self-lubricating tool, and the workpiece material's friction coefficient is only about 0.1, which can minimize adhesion and friction, as well as cutting force and temperature.
4. Nano-coated tools have recently become available. To meet various functional and performance criteria, the coating tool can be used with various combinations of various coating materials. The nano coating's nature allows the tool material to have excellent anti-friction and anti-wear properties, as well as self-lubricating properties, making it ideal for high-speed dry cutting.
Coated Tools in CNC: Characteristics and Features
1. Excellent mechanical and cutting performance: The CNC coated cutting tool blends the excellent mechanical and cutting performance of the substrate and coating materials, which not only retain the substrate's good durability and high strength, but also provide the coating's high stiffness, high wear resistance, and low friction coefficient. As a result, the coated tool's cutting speed is two times that of the uncoated tool, allowing for a higher feed rate. Cutting instruments that are coated have a longer life.
2. Wide processing range and universality: Coated tools in CNC tools have a broad processing range and universality. Several types of uncoated tools may be replaced by a single coated tool.
3. Coating thickness: As the coating thickness increases, the tool life increases as well. The tool life will stop growing once the coating thickness has reached saturation. It is easy to peel off a coating that is too thick, and wear resistance is low when the coating is too thin.
4. Regrinding property: The coated blade's regrinding property is low, the coating equipment is complicated, the process requirements are high, and the coating period is lengthy.
5. Coating materials: Tools with different coating materials have different cutting results. TiC coating has an advantage when cutting at low speeds; tin is more suitable when cutting at high speeds.
Coated CNC Tools Uses
CNC coated tools have a lot of potential in the field of CNC machining, and they will become a very significant tool variety in the future. End mills, reamers, drills, composite hole machining equipment, and gears have all had coating technology applied to them. Hobs, gear shaping cutters, gear shaving cutters, forming broaches, and various machine-clamped indexable inserts can be used to machine a range of steel and cast iron, heat-resistant alloys, and non-ferrous metals at high speeds.