Desirable Characteristics of Cutting Tool Material
- Hot hardness - Tool must be harder than the workpiece material. ...
- High yield strength at operating temperature.
- High toughness and bending strength.
- Excellent conductivity, low thermal expansion for good dimensional stability.
- High thermal shock resistant and fatigue resistant - They must withstand rapidly alternating temperature cycle during the cutting process.
- Excellent wear resistant- Required an acceptable tool life before it is replaced.
- Chemically stable and inert - Less soluble in workspace material and cutting fluid, corrosion resistant, oxidation resistant. Minimum adhesion and tool chip diffusion.
- High impact strength - They must resist the impact force due to vibrations or any other interrupted cutting.
What are the characteristics of good cutting tools?
Hot hardness - Tool must be harder than the workpiece material. They should maintain its hardness and strength even at high operating temperature (tool-work interaction causes high-temperature field at cutting zone ). Otherwise, the tool will break during the cutting process.
What is the hardness of the tool used to cut?
To cut chips from the workpiece, the hardness of the tool must be greater than the hardness of the workpiece material. The hardness of the cutting edge of the tool used for cutting metal materials is generally above 60HRC. For carbon tool steel materials, the hardness should be above 62HRC at room temperature;
What are the disadvantages of using a cutting tool?
During the working process, the cutting tool has to be subjected to great cutting pressure, friction and impact force, resulting in high cutting temperature. The tool works in such a high temperature, high pressure and severe friction environment, and the use of inappropriate materials will quickly wear or break the tool.
What are the properties of tool material?
The tool material must be tough enough so that it can work without fracture in impact forces occurs in interrupted cutting operations (such as milling, turning of splined shaft). It must be able to withstand vibrations occurred during machining. Property # 3. Wear Resistance: The term wear means loss of material.
What are the characteristics of cutting tool materials?
Desirable Characteristics of Cutting Tool MaterialHot hardness - Tool must be harder than the workpiece material. ... High yield strength at operating temperature.High toughness and bending strength.Excellent conductivity, low thermal expansion for good dimensional stability.More items...
What are the characteristics of tool material?
7 Main Properties of Good Tool Materials | Metal CuttingProperty # 2. Toughness:Property # 3. Wear Resistance:Property # 4. Chemical Stability or Inertness:Property # 5. Shock Resistance:Property # 6. Low Friction:Property # 7. Favourable Cost:
What are the desirable characteristics of a cutting tool material explain how these are satisfied in the case of high speed steel tools?
While each of these elements will add certain specific desirable characteristics, it can be generally state that they add deep hardening capability, high hot hardness, resistance to abrasive wear, and strength, to HSS.
What are the characteristics of metal cutting?
What Are The Main Features of Metal Cutting Tools?Toughness so that the tools do not fracture or chip.Hardness so that the tools can withstand the heat generated during the metal cutting process.Wear resistance so that the tool can have a long working life.
What are desirable properties of cutting fluids?
The desirable properties of cutting fluids in general are (Boston, 1952) 1) High thermal conductivity for cooling 2) Good lubricating qualities 3) High flash point, should not entail a fire hazard 4) Must not produce a gummy or solid precipitate at ordinary working temperatures 5) Be stable against oxidation.
Which of the following is not important characteristics of the cutting tool material?
It is the amount of hardness possessed by a material at normal temperature. Hardness is the property by which it can cut/scratch other metals. When hardness increases, brittleness also increases, and a material, which has too much of cold hardness, is not suitable for the manufacture of cutting tools.
What are the desired properties of the tool material for faster machining?
The more important of these requirements are given below: Hot hardness: This represents the capacity of the tool to retain its cutting ability and hardness at the high temperatures developed at the chip-tool interface. ... Wear resistance: ... Toughness: ... Low friction: ... Thermal conductivity: ... Low cost:
What are the mechanical properties of the material of cutting tool give examples?
hardness, hot hardness and pressure resistance.bending strength and toughness.inner bonding strength.wear resistance. oxidation resistance. small propensity for diffusion and adhesion. abrasion resistance. edge strength.
What are the 4 types of cutting tools?
Solid. In general, such a kind of cutter is employed as a lathe turning tool to perform the turning operations.Tipped Tool. This cutter was developed from different materials. ... Tool Bit. This is a non-rotating cutter. ... Grain Size. Cutting tools depend on the grain size and the number of grains. ... Pointed Tool.
What are the classification of cutting tools?
Currently, cutting tool materials are mainly divided into four categories: tool steel (including carbon instrument steel, Alloy steel, and high-speed steel), hard alloy, ceramic and ultra-hard cutting tool materials.
What are the different tool materials?
There are basically three types of tool material: tool steels; metal carbides; ceramics, including diamond-like materials.
What are the requirements of a good tool material?
Welcome back.Properties Required for Tool Materials: ... 1] Hot hardness: ... 2] Wear resistance: ... 3] Toughness: ... 4] Low friction: ... 5] Thermal conductivity: ... 6] Low cost:
What are materials used for machine tools?
Tool materialsCarbon steel. Steel with a carbon content ranging from 1 to 1.2 percent was the earliest material used in machine tools. ... High-speed steel. ... Cast alloys. ... Cemented tungsten carbide. ... Oxides. ... Diamonds.
What are the characteristics of a cutting tool?
When you choosing or making a cutting tool you should take care of its property, strength, and quality, below are some characteristic of cutting tool: Cutting tools should have high strength, hardness even at higher or lower temperatures.
What is the cutting tool according to the shape?
According to the shape of the cutting tool: According to the types of cutting: Types of material used for making the cutting tool: Cutting tools depends on the types of operation: With respect to the number of the cutting tool used in one tool: According to the direction of the tool movement:
What is the difference between a cutting tool and a grain?
Grain Size: Cutting tools depends on the number of grain and size of the grain, if suppose the grain size is big then it will remove more material and if the grain size is small it will remove less material. For example, abrasive type tool which is used in grinding wheels.
What is a single point cutting tool?
In a single-point cutting tool, there is only one cutting edge by which the material will remove, the examples of single-point cutting tools are turning the tool, shaping tools.
How many types of cutting tools are there?
Different types of cutting tools are used in different types of machine, according to the usage of the cutting tool, we can divide it into 7-types, and those are:
What is a pointed tool?
Pointed Tool: As the name suggests point, that means the tip of the tool is so fine, and edges end in a single line , few examples of these types of cutting tools are diamond pointed on the holder, hard carbide pointed tool. These are one of the costlier types of cutting tools.
What side is the right hand cutting tool?
In the right-hand cutting tool, the tool movement is from the right side to the left side.
What are the properties of cutting tools?
The desirable material properties include red hardness, abrasion resistance, toughness, thermal conductivity, specific heat and machinability.
What is toughness in a tool?
Definition: Toughness is a resistance to shock or impact forces, high unit pressure against the cutting edge. Higher the toughness, more shock load material can withstand. For example, Punches and turning tools (like lathe, milling, drilling etc.) require higher toughness. The Toughness of HSS (High-Speed Steel) measured by "Izod impact test" and toughness of cemented carbides measured by "Transverse rupture test".
What is abrasion resistance?
Definition: Abrasion resistance is defined as an ability to resist wear. Abrasion resistance depends on hardness as well as undissolved carbides. Resistance to wear increases as carbon and alloying elements increase. Steels with higher carbon, chromium, tungsten, molybdenum and vanadium percentage have higher abrasion resistance. Carbides percentage are improved by adding a small percentage of tantalum.
What is metal manufacturing?
Today manufacturing is a vital activity of a production unit. Metal manufacturing process deals with cutting, fabricating and finishing with a tool corresponding to that process. To survive during the machining operation, the machine tool has to be strong enough to withstand the forces, heats and environment conditions. This includes properties like red hardness, abrasion/ wear resistance, toughness, thermal conductivity and many more.
Which is better, thermal conductivity or conduction?
Higher the thermal conductivity of any material, better is the ability to transmit the heat by conduction. The material also should contain better specific heat (amount of heat required to raise the temperature of a unit mass of a substance by unit degree) to disperse heat generated due to cutting operations.
What are the properties of cutting tools?
During the working process, the cutting tool has to be subjected to great cutting pressure, friction and impact force, resulting in high cutting temperature.
What is the basic characteristic that a tool material should have?
High hardness and good wear resistance. Hardness is the basic characteristic that the tool material should have. To cut chips from the workpiece, the hardness of the tool must be greater than the hardness of the workpiece material.
How is thermal hardness measured?
It is usually measured by maintaining high hardness, wear resistance, strength and toughness at high temperatures, also known as thermal hardness.
What is the hardness of a metal cutting tool?
The hardness of the cutting edge of the tool used for cutting metal materials is generally above 60HRC.
What are the requirements for a tool?
Therefore, the tool material should be able to meet some basic requirements. 1. High hardness and good wear resistance.
When was tungsten carbide invented?
Therefore, from the 1920s to the 1930s, people invented tungsten-cobalt-titanium cemented carbide.
What is the reasonable choice of tool material?
The reasonable choice of tool material is an important part of the cutting process, which largely determines the level of cutting productivity, tool consumption and processing costs, the size of the machining accuracy and surface quality .
What are cutting tools made of?
Many types of tool materials, ranging from high carbon steel to ceramics and diamonds, are used as cutting tools in today’s metalworking industry. It is important to be aware that differences do exist among tool materials, what these differences are, and the correct application for each type of material. The various tool manufacturers assign many ...
What is the oldest tool material?
Plain carbon tool steel is the oldest of the tool materials dating back hundreds of years. In simple terms, it is a high-carbon steel, which contains about 1.05% carbon. This high carbon content allows the steel to be hardened, offering greater resistance to abrasive wear. Plain high carbon steel served its purpose well for many years.
What is carbon steel?
Plain carbon tool steel is the oldest of the tool materials dating back hundreds of years. In simple terms, it is a high-carbon steel, which contains about 1.05% carbon. This high carbon content allows the steel to be hardened, offering greater resistance to abrasive wear. Plain high carbon steel served its purpose well for many years. However, because it is quickly over tempered (softened) at relatively low cutting temperatures (300 to 500°F), it is now rarely used as cutting tool material except in files, saw blades, chisels, etc. The use of plain high carbon steel is limited to low heat applications.
What is the temperature of plain high carbon steel?
However, because it is quickly over tempered (softened) at relatively low cutting temperatures (300 to 500°F), it is now rarely used as cutting tool material except in files, saw blades, chisels, etc. The use of plain high carbon steel is limited to low heat applications.
Why are surface treatments used?
Many surface treatments have been developed in an attempt to extend tool life, reduce power consumption, and to control other factors that affect operating conditions and costs. Some of these treatments have been used for many years and have proven to have some value.
What is tungsten carbide?
The term “tungsten carbide” describes a comprehensive family of hard carbide compositions used for metal cutting tools, dies of various types, and wear parts. In general, these materials are composed of the carbides of tungsten, titanium, tantalum, or some combination of these, sintered or cemented in a matrix binder, usually cobalt.
What is the second compacting method?
A second compacting method is the hot pressing of grade powders in graphite dies at the sintering temperature. After cooling, the part has attained full hardness. Because the graphite dies are expendable, this system is generally used only when the part to be produced it too large for cold pressing and sintering.
What is the tool material that must be tough enough to work?
The tool material must be tough enough so that it can work without fracture in impact forces occurs in interrupted cutting operations (such as milling, turning of splined shaft). It must be able to withstand vibrations occurred during machining.
Why are diamond tools not used in common applications?
For example, diamond tools are not used for common applications due to its high cost.
What is the property of hot hardness?
Property # 1. Hot Hardness: Generally hardness is measured at room temperature. But the term Hot hardness indicates that the hardness at elevated temperature. We know that the hardness decreases as temperature increases. In metal cutting, heat is generated during the process.
