Search

Please enter a keyword or what you are looking for in the field below to search.

alt
Search result
There is no result for your search, please check again.
    alt alt alt alt
    alt alt alt alt
    alt

    How to choose the right tools: cutting tools material and performance

    The material of the tool is an important factor affecting the processing efficiency, quality, cost, and durability. Since the industrial revolution, the material of the cutting tool has been improved continuously, from the beginning of carbon steel cutter to high-speed steel cutter, carbide cutter, ceramic cutter and superhard cutting tools have been constantly innovated and adjusted to increase the cutting speed by more than 100 times. What is the basic performance of the cutting tools and what are the common tool materials?

    Scroll

    Basic tools performance

    Choosing the right tools can prolong tool life, improve processing efficiency, quality and reduce costs. Therefore, we must understand the workpiece material, machine tool performance, mechanical quality and cutting methods first. Cutting is in an ever-changing environment as it need to stand high temperature, high pressure, impact, friction, vibration…etc. There are some unexpected situations during cutting. At this time, understanding the basic performance of the tools will help the process.

    【Read more】Laymen can also understand the types of mechanical processing

    Hardness

    The material hardness of tools usually needs to be greater than workpiece, and it is required to be over 60HRC, the harder the tool materials are, the greater wear resistance it can be. Many processors usually choose the appropriate cutting tool according to the sum of the hardness at room temperature and at high temperature.

    • Cold hardness,The higher hardness of the tool made the cutting ability strong, but it will with lower toughness. With enough hardness enables tool can smoothly remove the workpiece material, and the blade is not easy to wear.
    • Red hardness,Under high-speed cutting must produce high temperature. At this time, although the tool turns dark red, the cutting ability will still exist. This is red hardness. The higher hardness of the tool, the better high-speed cutting can be done.

    In addition, the hardness of tool materials is usually based on Rockwell hardness (HRC), HRA is used to measure carbide tools, and high-speed steel tools are measured by HRC.

    Abrasion resistance and toughness

    Cutting processing will cause the tool to successfully remove the workpiece material with great force, therefore, if the tool is not wear-resistant, the cutting effect and tool life will be decreased.

    Heat resistance

    The heat resistance of the tool material must be high in order to stand high cutting temperatures and have good antioxidative capacity.

    Common tool materials

    In recent years, due to the requirements of mass production, the production capacity has also been continuously improved. In order to maximize the performance of the machine tool, the combination of cutting tools is very important. Therefore, the tools also need to be significantly developed and improved. At present, each cutting tool material has its own characteristic to match different processing requirements. The tools will mainly focus on manufacturing cost, ability of refractoriness under load, friction coefficient, high wear resistance, good thermal conductivity, etc. The common tool materials are as follows:

    • Tool steel: This is one of the important materials in mechanical manufacturing and processing. It is often used in measuring equipment, cutting tools and molds. It is composed of high carbon steel (carbon content is 0.6-1.5%), and other alloy element will be added according to the purpose of usage. Tools can be divided into carbon steel tool, carbide tool and high-speed steel according to their chemical composition, and can be divided into cutting tool steel, impact-resistant tool steel, wear-resistant tool steel and hot working tool steel according to their application.
    • High carbon steel: This kind of tool has high carbon content which is about 0.7-1.5%. After heat treatment, the hardness can reach HRC60-65, but the heat resistance is only 200ºC, so it is limited easily. When the temperature reaches 300ºC, the processing rate will not increase. High carbon steel is more suitable for short-term, low speed cutting tools, such as scrapers, drills, or screw taps.


    • High-speed steel: This tool is often used to cut metals with low hardness. It is one kind of alloy steel. The main components are tungsten, chromium, cobalt, molybdenum, vanadium, carbon and other six elements. It is often used as twist drill, broach tool, gear cutter, one of the main materials of other complex-shaped knives, and it is different from high-speed steel, with red hardness, because the cutting speed is more than twice of high-carbon steel, so it is called high-speed steel.


    • Cemented carbide: The main component are tungsten carbide and cobalt, accounting for 99% of all components, and 1% is other metals, so it is called tungsten steel. Cemented carbide has high hardness, good wear resistance, high heat resistance, and great compressive strength and even the cutting rate is three times of high-speed steel.


    • Ceramics and Cermets: The characteristics of ceramics and cermets are high hardness, great wear resistance and heat resistance, and a low friction coefficient, and the chips are not easy to stick to the cutter. There are two main types. One is Aluminium oxide, and another is silicon nitride, but the disadvantage of the former is the low bending strength, poor impact resistance which will easily to chip slightly, the latter has better impact performance and can process chilled steel and chilled cast iron.

    Super hard tool materials

    • Natural diamond: This is the hardest material in nature. Although it has great wear resistance, it is expensive. It is mainly used for parts which requires high machining precision and surface roughness; however, the disadvantage is that it has an affinity with iron materials which is not suitable for machining steel or cast iron. 


    • Polycrystalline diamond: This is the hardest material man made at present. It is a carbon allotrope. It is transformed from stone grinding under high pressure and temperature. It has high hardness and good wear resistance. It can replace natural diamond to make turning tool, boring tool, milling cutters and other inserts.


    • Cubic boron nitride: This is a new type of artificially synthesized tool material. It is converted from graphitic BN by adding catalyst under high temperature and pressure. It has high hardness, wear resistance, and great thermostability. It can be used to process high temperature alloys. Processing chilled steel and cast iron efficiently.

    Conclusion

    Choosing the right tool can effectively improve processing efficiency, quality and reduce costs, so it is helpful to understand the performance and material of the tool from all aspects, moreover, other factors such as workpiece material, machine tool performance, cutting method, etc. More helpful to optimize the process.

    Main photo by Zhihu

    References kknews / Brucenote

    This article was written by Machsync, please do not distribute, give or sell for commercial use or in any way. Any use such as reprinting, excerpting, copying, and creating images is prohibited without permission.

    For reprinting, please contact Machsync.