In recent years, the development of multi-functional and high-functionality of mechanical products has been very strong, requiring parts to be miniaturized and miniaturized. In order to meet some requirements, the materials used must have high hardness, high toughness and high wear resistance, and materials with these characteristics are also difficult to process, and new difficult materials are emerging. Difficult to process materials have emerged with the development of the times and professional fields, and their unique processing technologies have continued to develop with the research and development of the times and various professional fields.
On the other hand, with the advent of the information society, the information on the cutting technology of difficult-to-machine materials can also communicate with each other via the Internet. Therefore, in the future, information on the machining data of difficult-to-machine materials will be more substantial, and the processing efficiency will inevitably be further improved. Taking the machining of difficult-to-machine materials as the core, the development trend of this technology in recent years is introduced.
Difficult to process materials in the field of cutting
In the cutting process, the tool wear usually includes the following two forms: (1) wear due to mechanical action, such as chipping or abrasive wear; (2) wear due to heat and chemical action, such as bonding, diffusion, Wear such as corrosion, and softening and melting by the cutting edge to cause breakage, thermal fatigue, thermal cracking, and the like.
When cutting difficult-to-machine materials, the above-mentioned tool wear occurs in a short time, which is due to the fact that the material to be processed is more likely to cause tool wear. For example, most difficult-to-machine materials have a low thermal conductivity, and it is difficult to diffuse heat during cutting, resulting in a high temperature at the tip of the tool and a significant influence on the cutting edge. As a result of this effect, the bonding strength of the tool material binder at a high temperature is lowered, and particles such as wc (tungsten carbide) are easily separated, thereby accelerating tool wear. In addition, some components of the tool material that are difficult to process are reacted under high temperature conditions, and are analyzed, detached, or other compounds are formed, which accelerates the formation of tool wear such as chipping.
When cutting high-hardness, high-toughness materials, the cutting edge temperature is high, and there is also a similar tool wear when cutting difficult materials. For example, when cutting high-hardness steel, the cutting force is larger than that of cutting general steel. If the rigidity of the tool is insufficient, it will cause chipping and the like, which will make the tool life unstable and shorten the tool life, especially when machining short-cut workpiece materials. It will cause crater wear near the cutting edge, and the tool breakage will occur in a short time.
When cutting superalloys, due to the high hardness of the material, the stress is concentrated at the tip of the blade during cutting, which will cause plastic deformation of the cutting edge. At the same time, the boundary wear is more serious due to work hardening.
Due to these characteristics, when the user is required to cut difficult materials, the cutting conditions of the tool must be carefully selected to obtain the desired processing result.
Difficult to machine materials processing should pay attention to the problem
Machining is roughly divided into turning, milling, and centring-based cutting (bit, end mill end cutting, etc.), and the cutting heat of these cuttings has different effects on the cutting edge. Turning is a continuous cutting, the cutting edge bears no significant change in cutting force, the cutting heat acts continuously on the cutting edge; milling is a kind of intermittent cutting, the cutting force acts intermittently on the cutting edge, vibration will occur during cutting, and the cutting edge will be heated. The effect is that the cooling is alternately performed during heating and non-cutting during cutting, and the total heat is less than that during turning.
The cutting heat during milling is an intermittent heating phenomenon, and the cutter teeth are cooled when they are not cut, which will facilitate the tool life extension. The Japan Institute of Physics and Chemistry has conducted a comparative test on the life of turning and milling tools. The tool used for milling is a ball end mill, and the turning is a general turning tool. The cutting conditions of the same material are the same (the cutting depth and the feed amount are different due to different cutting methods). Cutting speed can only be achieved in the same environment. The results show that milling is more beneficial to extend tool life.
When cutting with a tool with a heart edge (ie cutting speed = 0 m/min), a ball end mill, etc., the tool life near the core is often low, but it is still stronger than turning.
When cutting difficult materials, the cutting edge is greatly affected by heat, which often reduces the tool life. If the cutting method is milling, the tool life will be relatively longer. However, difficult-to-machine materials cannot be milled from start to finish. There is always a need for turning or drilling. Therefore, corresponding technical measures should be taken for different cutting methods to improve processing efficiency.
Cutting tool material for difficult-to-machine materials
Cbn high temperature hardness has the highest tool material and is most suitable for machining difficult materials. The new coated cemented carbide is made of ultra-fine grain alloy as the matrix, and is coated with a high-temperature and good-hardness coating material. This material has excellent wear resistance and can also be used for one of the excellent tool materials for difficult-to-machine material cutting.
Titanium and titanium alloys, which are difficult to process materials, have high chemical activity and low thermal conductivity. Diamond tools can be used for cutting. The cbn sintered body cutter is suitable for cutting high hardness steel and cast iron. The higher the cbn content, the longer the tool life and the higher the cutting amount. It has been reported that a sintered cbn sintered body has not been developed.
The diamond sintered body cutter is suitable for cutting materials such as aluminum alloy and pure copper. The diamond cutter has a sharp cutting edge, high thermal conductivity, and less heat retention at the tip of the blade, which can control the adhesion of built-up edges and the like to a minimum. When cutting pure titanium-titanium alloy, the single-crystal diamond tool is more stable and can extend the tool life. 
Coated cemented carbide tools are suitable for cutting a variety of difficult-to-machine materials, but the coating properties (single-coat composite coating) vary widely. Therefore, suitable coating tool materials should be selected according to different processing objects. According to reports, diamond-coated hard alloy dlc (diamondlikecarbon) coated cemented carbide has recently been developed, which has further expanded the application range of coated tools and has been used in high-speed machining.
Cutting difficult tool shapes
When cutting difficult materials, the tool shape is optimized to maximize tool material performance. Choosing the tool geometry corresponding to the characteristics of the difficult-to-machine material, such as the rake angle, the back angle, and the plunging angle, properly handles the blade tip, which greatly affects the cutting accuracy and prolongs the tool life. Therefore, the shape of the tool must not be taken lightly. However, with the popularization and application of high-speed milling technology, a small depth of cut has been gradually adopted to reduce the tooth load, and the up-cut milling is used to increase the feed speed. Therefore, the design of the cutting edge shape has also changed.
When drilling difficult-to-machine materials, increase the drill angle, perform cross-shaped grinding, and reduce the effective way of torque cutting heat. It can control the contact area between cutting and cutting surface to a minimum, which will improve the tool life. The cutting conditions are very favorable. When the drill bit is drilled, the cutting heat is easily trapped near the cutting edge, and the chip removal is also difficult. When cutting difficult materials, these problems are more prominent and must be given enough attention.
In order to facilitate chip evacuation, a coolant discharge port is usually provided on the rear side of the cutting edge of the drill to supply sufficient water-soluble coolant or mist coolant to make the chip removal smoother. Very ideal. In recent years, some coating materials with good lubricating properties have been developed. These materials can be dry-drilled when they are coated with a 3 to 5d shallow hole after being coated with a drill bit surface.
Hole finishing has traditionally been performed by boring, but it has recently been changed from conventional continuous cutting to discontinuous cutting with contour cutting. This method is more advantageous for improving chip evacuation performance and extending tool life. Therefore, this type of intermittent cutting boring tool is designed and applied to the cnc cutting of automotive parts. In terms of threaded hole machining, spiral cutting interpolation has also been adopted, and end mills for thread cutting have been put on the market in large quantities.
As described above, this transition from the original continuous cutting to the intermittent cutting is carried out as the understanding of cnc cutting is deepened, which is a gradual process. When cutting difficult materials with this type of cutting, the cutting stability can be maintained and the tool life can be extended.
Difficult to machine material cutting conditions
The cutting conditions of difficult-to-machine materials have always been set relatively low. With the improvement of tool performance, the emergence of high-speed and high-precision cnc machine tools, and the introduction of high-speed milling methods, at present, difficult-to-machine material cutting has entered a period of high-speed machining and long tool life.
Now, using a small depth of cut to reduce the cutting edge of the tool, which can improve the cutting speed feed rate processing method, has become the best way to cut difficult materials. Of course, it is also extremely important to choose the tool geometry that is unique to the difficult material of the difficult material, and to optimize the cutting path of the tool. For example, when drilling materials such as stainless steel, since the thermal conductivity of the material is very low, it is necessary to prevent the cutting heat from being largely retained on the cutting edge. For this reason, intermittent cutting should be used as much as possible to avoid frictional heat generation on the cutting surface of the cutting edge. Helps extend tool life and ensure stable cutting. When the ball end mill is used for rough machining of difficult-to-machine materials, the tool-shaped jig should be well matched, which can improve the clamping precision of the cutting part of the tool, so that the feed per tooth can be improved under high-speed rotation conditions. To the maximum, it also extends tool life.
On the other hand, with the advent of the information society, the information on the cutting technology of difficult-to-machine materials can also communicate with each other via the Internet. Therefore, in the future, information on the machining data of difficult-to-machine materials will be more substantial, and the processing efficiency will inevitably be further improved. Taking the machining of difficult-to-machine materials as the core, the development trend of this technology in recent years is introduced.
Difficult to process materials in the field of cutting
In the cutting process, the tool wear usually includes the following two forms: (1) wear due to mechanical action, such as chipping or abrasive wear; (2) wear due to heat and chemical action, such as bonding, diffusion, Wear such as corrosion, and softening and melting by the cutting edge to cause breakage, thermal fatigue, thermal cracking, and the like.
When cutting difficult-to-machine materials, the above-mentioned tool wear occurs in a short time, which is due to the fact that the material to be processed is more likely to cause tool wear. For example, most difficult-to-machine materials have a low thermal conductivity, and it is difficult to diffuse heat during cutting, resulting in a high temperature at the tip of the tool and a significant influence on the cutting edge. As a result of this effect, the bonding strength of the tool material binder at a high temperature is lowered, and particles such as wc (tungsten carbide) are easily separated, thereby accelerating tool wear. In addition, some components of the tool material that are difficult to process are reacted under high temperature conditions, and are analyzed, detached, or other compounds are formed, which accelerates the formation of tool wear such as chipping.
When cutting high-hardness, high-toughness materials, the cutting edge temperature is high, and there is also a similar tool wear when cutting difficult materials. For example, when cutting high-hardness steel, the cutting force is larger than that of cutting general steel. If the rigidity of the tool is insufficient, it will cause chipping and the like, which will make the tool life unstable and shorten the tool life, especially when machining short-cut workpiece materials. It will cause crater wear near the cutting edge, and the tool breakage will occur in a short time.
When cutting superalloys, due to the high hardness of the material, the stress is concentrated at the tip of the blade during cutting, which will cause plastic deformation of the cutting edge. At the same time, the boundary wear is more serious due to work hardening.
Due to these characteristics, when the user is required to cut difficult materials, the cutting conditions of the tool must be carefully selected to obtain the desired processing result.
Difficult to machine materials processing should pay attention to the problem
Machining is roughly divided into turning, milling, and centring-based cutting (bit, end mill end cutting, etc.), and the cutting heat of these cuttings has different effects on the cutting edge. Turning is a continuous cutting, the cutting edge bears no significant change in cutting force, the cutting heat acts continuously on the cutting edge; milling is a kind of intermittent cutting, the cutting force acts intermittently on the cutting edge, vibration will occur during cutting, and the cutting edge will be heated. The effect is that the cooling is alternately performed during heating and non-cutting during cutting, and the total heat is less than that during turning.
The cutting heat during milling is an intermittent heating phenomenon, and the cutter teeth are cooled when they are not cut, which will facilitate the tool life extension. The Japan Institute of Physics and Chemistry has conducted a comparative test on the life of turning and milling tools. The tool used for milling is a ball end mill, and the turning is a general turning tool. The cutting conditions of the same material are the same (the cutting depth and the feed amount are different due to different cutting methods). Cutting speed can only be achieved in the same environment. The results show that milling is more beneficial to extend tool life.
When cutting with a tool with a heart edge (ie cutting speed = 0 m/min), a ball end mill, etc., the tool life near the core is often low, but it is still stronger than turning.
When cutting difficult materials, the cutting edge is greatly affected by heat, which often reduces the tool life. If the cutting method is milling, the tool life will be relatively longer. However, difficult-to-machine materials cannot be milled from start to finish. There is always a need for turning or drilling. Therefore, corresponding technical measures should be taken for different cutting methods to improve processing efficiency.
Cutting tool material for difficult-to-machine materials
Cbn high temperature hardness has the highest tool material and is most suitable for machining difficult materials. The new coated cemented carbide is made of ultra-fine grain alloy as the matrix, and is coated with a high-temperature and good-hardness coating material. This material has excellent wear resistance and can also be used for one of the excellent tool materials for difficult-to-machine material cutting.
Titanium and titanium alloys, which are difficult to process materials, have high chemical activity and low thermal conductivity. Diamond tools can be used for cutting. The cbn sintered body cutter is suitable for cutting high hardness steel and cast iron. The higher the cbn content, the longer the tool life and the higher the cutting amount. It has been reported that a sintered cbn sintered body has not been developed.
The diamond sintered body cutter is suitable for cutting materials such as aluminum alloy and pure copper. The diamond cutter has a sharp cutting edge, high thermal conductivity, and less heat retention at the tip of the blade, which can control the adhesion of built-up edges and the like to a minimum. When cutting pure titanium-titanium alloy, the single-crystal diamond tool is more stable and can extend the tool life. 
Coated cemented carbide tools are suitable for cutting a variety of difficult-to-machine materials, but the coating properties (single-coat composite coating) vary widely. Therefore, suitable coating tool materials should be selected according to different processing objects. According to reports, diamond-coated hard alloy dlc (diamondlikecarbon) coated cemented carbide has recently been developed, which has further expanded the application range of coated tools and has been used in high-speed machining.
Cutting difficult tool shapes
When cutting difficult materials, the tool shape is optimized to maximize tool material performance. Choosing the tool geometry corresponding to the characteristics of the difficult-to-machine material, such as the rake angle, the back angle, and the plunging angle, properly handles the blade tip, which greatly affects the cutting accuracy and prolongs the tool life. Therefore, the shape of the tool must not be taken lightly. However, with the popularization and application of high-speed milling technology, a small depth of cut has been gradually adopted to reduce the tooth load, and the up-cut milling is used to increase the feed speed. Therefore, the design of the cutting edge shape has also changed.
When drilling difficult-to-machine materials, increase the drill angle, perform cross-shaped grinding, and reduce the effective way of torque cutting heat. It can control the contact area between cutting and cutting surface to a minimum, which will improve the tool life. The cutting conditions are very favorable. When the drill bit is drilled, the cutting heat is easily trapped near the cutting edge, and the chip removal is also difficult. When cutting difficult materials, these problems are more prominent and must be given enough attention.
In order to facilitate chip evacuation, a coolant discharge port is usually provided on the rear side of the cutting edge of the drill to supply sufficient water-soluble coolant or mist coolant to make the chip removal smoother. Very ideal. In recent years, some coating materials with good lubricating properties have been developed. These materials can be dry-drilled when they are coated with a 3 to 5d shallow hole after being coated with a drill bit surface.
Hole finishing has traditionally been performed by boring, but it has recently been changed from conventional continuous cutting to discontinuous cutting with contour cutting. This method is more advantageous for improving chip evacuation performance and extending tool life. Therefore, this type of intermittent cutting boring tool is designed and applied to the cnc cutting of automotive parts. In terms of threaded hole machining, spiral cutting interpolation has also been adopted, and end mills for thread cutting have been put on the market in large quantities.
As described above, this transition from the original continuous cutting to the intermittent cutting is carried out as the understanding of cnc cutting is deepened, which is a gradual process. When cutting difficult materials with this type of cutting, the cutting stability can be maintained and the tool life can be extended.
Difficult to machine material cutting conditions
The cutting conditions of difficult-to-machine materials have always been set relatively low. With the improvement of tool performance, the emergence of high-speed and high-precision cnc machine tools, and the introduction of high-speed milling methods, at present, difficult-to-machine material cutting has entered a period of high-speed machining and long tool life.
Now, using a small depth of cut to reduce the cutting edge of the tool, which can improve the cutting speed feed rate processing method, has become the best way to cut difficult materials. Of course, it is also extremely important to choose the tool geometry that is unique to the difficult material of the difficult material, and to optimize the cutting path of the tool. For example, when drilling materials such as stainless steel, since the thermal conductivity of the material is very low, it is necessary to prevent the cutting heat from being largely retained on the cutting edge. For this reason, intermittent cutting should be used as much as possible to avoid frictional heat generation on the cutting surface of the cutting edge. Helps extend tool life and ensure stable cutting. When the ball end mill is used for rough machining of difficult-to-machine materials, the tool-shaped jig should be well matched, which can improve the clamping precision of the cutting part of the tool, so that the feed per tooth can be improved under high-speed rotation conditions. To the maximum, it also extends tool life.
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1.Waterproof, tide proof, air proof and non-poisonous resealable plastic pouch
2. Available in customers' designs, size range: 4(width)×6(length)cm to 40(width)×50(length)cm.
3. Used to pack food, medicine, medical apparatus, electronic products, cosmetic, handicraft.
4. Good service and reasonable price
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