Titanium alloy material precision machining technology
As we all know, precision machining in the aerospace industry is very demanding for materials, of course, one side is to meet the particularity of aviation equipment, and more importantly because of the impact of the aerospace environment. Due to the special environmental impact, the general materials on the market certainly cannot meet the needs of the environment. Therefore, some unique materials will inevitably be substituted. Today to introduce a more commonly used materials, that is, titanium, especially aerospace, is more common, why the use of this material more? That makes a certain relationship with its characteristics.
Titanium alloy, its small proportion, determines the quality of small, high strength and hot strength, determines the hardness and high temperature, and resistance to sea water and acid-base corrosion and a series of excellent physical and mechanical properties, no matter in what environment Can be used, another point, the deformation coefficient is small, so in aerospace, aviation, shipbuilding, petroleum, chemical and other industries have been widely used.
Because titanium alloy with the above and the common material is not the same place, also decided that it has great difficulty in precision machining, many machining factories are reluctant to process this material, do not know how to process this material. To this end, Sune lubricants after a long period of understanding and communication with some titanium processing customers, sorted out some small tips to give you!
Due to the trivial deformation coefficient of titanium alloy, high cutting temperature, high tip stress, serious processing and hardening, resulting in the cutting process, the tool is easy to wear, chipping, cutting quality is difficult to guarantee. How to do cutting?
Titanium alloy cutting, the cutting force is not large, work hardening is not serious, easy to get better surface finish, but the titanium alloy thermal conductivity, high cutting temperature, tool wear larger, tool durability is low, the tool should be used with titanium Chemical affinity and small, high thermal conductivity, high strength, small grain size of tungsten and cobalt carbide cutting tools, such as YG8, YG3 and other tools. In the turning process of titanium alloy, chip breaking is a processing problem, especially for the processing of pure titanium. In order to realize the purpose of chip breaking, the cutting part can be sharpened into a full-arc chip trough. After the wide, easy to chip out to the outside, so that will not let the ship wrapped around the workpiece surface, causing the workpiece surface scratches.
Titanium cutting deformation coefficient is small, the contact area of ??the knife and the crumbs small, high cutting temperature, in order to reduce the heat generated by cutting, ① lathe rake angle should not be too large, Carbide lathe front angle generally take 5-8 degrees , Due to the high hardness of titanium alloy, in order to increase the impact strength of the turning tool, the lathe angle should not be too large, generally take 5 °, in order to strengthen the tip part of the strength and improve the cooling conditions and improve tool impact Ability to use a larger negative tangent tilt angle.
Control of a reasonable cutting speed, should not be too hasty, and in the process of using titanium alloy cutting fluid cooling, which can effectively improve tool durability, and select the rationing of the feed.
Drilling is also more commonly used, titanium alloy drilling more difficult, often appear in the process of burning knife and broken drill phenomenon. The main reason is imperfect drill bit grinding, chip evacuation is not timely, poor cooling and poor system technology caused by the reasons. Depending on the drill bit diameter, narrowing chisel edge width of 0.5mm in general. In order to reduce the axial force to reduce the shock caused by the resistance. At the same time at the tip of the drill 5-8mm distances, drill bit narrow margin, leaving 0.5mm or so, is conducive to drill bit chip removal. The geometry must be sharpened correctly. The two cutting edges must be symmetrical so that only one edge of the bit is not able to cutting. All cutting forces are concentrated on one side, prematurely wearing the bat and even causing chipping due to skidding. Always keep the blade sharp, when the blade becomes dull, stop drilling immediately, resharpen the drill bit. If you use a blunt drill to continue forcibly cut, the drill bit will quickly burn owing to frictional heat and the drill will be scrapped due to annealing. At the same time, the hardened layer of the workpiece is thickened, which increases the difficulty and the number of sharpening drills for subsequent drilling. By drilling depth requirements, should be shortened bit length, increase the thickness of the core to increase rigidity, to prevent the drilling is jitter caused by collapse. It has been proved by practice that the drill bit length of φ15 is longer than that of the slow 195. So the length of the selection is also essential.
After the above two common processing points of view, titanium alloy processing is relatively difficult, but after a very good processing or can be processed to a good precision parts, aerospace equipment, titanium alloy parts.
As we all know, precision machining in the aerospace industry is very demanding for materials, of course, one side is to meet the particularity of aviation equipment, and more importantly because of the impact of the aerospace environment. Due to the special environmental impact, the general materials on the market certainly cannot meet the needs of the environment. Therefore, some unique materials will inevitably be substituted. Today to introduce a more commonly used materials, that is, titanium, especially aerospace, is more common, why the use of this material more? That makes a certain relationship with its characteristics.
Titanium alloy, its small proportion, determines the quality of small, high strength and hot strength, determines the hardness and high temperature, and resistance to sea water and acid-base corrosion and a series of excellent physical and mechanical properties, no matter in what environment Can be used, another point, the deformation coefficient is small, so in aerospace, aviation, shipbuilding, petroleum, chemical and other industries have been widely used.
Because titanium alloy with the above and the common material is not the same place, also decided that it has great difficulty in precision machining, many machining factories are reluctant to process this material, do not know how to process this material. To this end, Sune lubricants after a long period of understanding and communication with some titanium processing customers, sorted out some small tips to give you!
Due to the trivial deformation coefficient of titanium alloy, high cutting temperature, high tip stress, serious processing and hardening, resulting in the cutting process, the tool is easy to wear, chipping, cutting quality is difficult to guarantee. How to do cutting?
Titanium alloy cutting, the cutting force is not large, work hardening is not serious, easy to get better surface finish, but the titanium alloy thermal conductivity, high cutting temperature, tool wear larger, tool durability is low, the tool should be used with titanium Chemical affinity and small, high thermal conductivity, high strength, small grain size of tungsten and cobalt carbide cutting tools, such as YG8, YG3 and other tools. In the turning process of titanium alloy, chip breaking is a processing problem, especially for the processing of pure titanium. In order to realize the purpose of chip breaking, the cutting part can be sharpened into a full-arc chip trough. After the wide, easy to chip out to the outside, so that will not let the ship wrapped around the workpiece surface, causing the workpiece surface scratches.
Titanium cutting deformation coefficient is small, the contact area of ??the knife and the crumbs small, high cutting temperature, in order to reduce the heat generated by cutting, ① lathe rake angle should not be too large, Carbide lathe front angle generally take 5-8 degrees , Due to the high hardness of titanium alloy, in order to increase the impact strength of the turning tool, the lathe angle should not be too large, generally take 5 °, in order to strengthen the tip part of the strength and improve the cooling conditions and improve tool impact Ability to use a larger negative tangent tilt angle.
Control of a reasonable cutting speed, should not be too hasty, and in the process of using titanium alloy cutting fluid cooling, which can effectively improve tool durability, and select the rationing of the feed.
Drilling is also more commonly used, titanium alloy drilling more difficult, often appear in the process of burning knife and broken drill phenomenon. The main reason is imperfect drill bit grinding, chip evacuation is not timely, poor cooling and poor system technology caused by the reasons. Depending on the drill bit diameter, narrowing chisel edge width of 0.5mm in general. In order to reduce the axial force to reduce the shock caused by the resistance. At the same time at the tip of the drill 5-8mm distances, drill bit narrow margin, leaving 0.5mm or so, is conducive to drill bit chip removal. The geometry must be sharpened correctly. The two cutting edges must be symmetrical so that only one edge of the bit is not able to cutting. All cutting forces are concentrated on one side, prematurely wearing the bat and even causing chipping due to skidding. Always keep the blade sharp, when the blade becomes dull, stop drilling immediately, resharpen the drill bit. If you use a blunt drill to continue forcibly cut, the drill bit will quickly burn owing to frictional heat and the drill will be scrapped due to annealing. At the same time, the hardened layer of the workpiece is thickened, which increases the difficulty and the number of sharpening drills for subsequent drilling. By drilling depth requirements, should be shortened bit length, increase the thickness of the core to increase rigidity, to prevent the drilling is jitter caused by collapse. It has been proved by practice that the drill bit length of φ15 is longer than that of the slow 195. So the length of the selection is also essential.
After the above two common processing points of view, titanium alloy processing is relatively difficult, but after a very good processing or can be processed to a good precision parts, aerospace equipment, titanium alloy parts.
