Application of the hottest stainless steel turning

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Stainless steel turning applications

the latest turning blade materials and chip breaking grooves provide higher capabilities for stainless steel turning

stainless steel, which is widely used in industry, poses a great challenge to the tool industry. Their machinability must be considered in the research and development of new turning blade materials and chip breaking grooves. A group of stainless steel materials that provide long service life and easy cutting in corrosive environments such as chemical, food, paper and pulp industries are increasingly used. These materials are usually chromium based iron or carbon steel that provide good corrosion resistance. Other groups of stainless steel materials containing chromium and nickel with different specific gravity are used in the aviation industry where high tensile strength and corrosion resistance are required. They range from low nickel alloys with medium machining difficulty to high-temperature alloys with very difficult machining

machining challenges

although stainless steel has great machinability, they are very sticky, which will cause potential problems such as chip sticking, chip buildup and the resulting "pull-out" of coating particles, even particles at the junction of coating and substrate. However, major cutting tool companies have been designing the latest core cemented carbide materials and chip breaking grooves for today's assembly line, considering these failure modes, and by extension, providing turning blades. Now, it is easy to obtain an economical solution for mass production of stainless steel that is easy to cut to medium difficult processing range

reconstituted cemented carbide material according to toughness

shangao tool is one of the cutting tool suppliers with a complete range of new core turning tool materials designed to improve performance in a wide range of processing conditions and Applications (including approaching the final shape and stainless steel processing). In terms of cemented carbide, shangao company thoroughly reorganized its core turning materials for general machining (tp200) and heavy roughing (tp300) to provide cutting edges with better adhesion and toughness between the substrate and the underlying coating. Both materials are coated with a composite coating composed of titanium carbonitride (TiCN), aluminum oxide (Al2O3) and titanium nitride (TIN) on the substrate with cobalt rich region

according to bobgoulding, fixed product manager of carboloy, the restructured material provides important characteristics for improving the processing of stainless steel materials. They consist of a tough coating that effectively resists pull-out and a smooth, hard top coating that better resists sticking chips and chip buildup

Goulding said that through the progress of coating deposition process - medium temperature chemical vapor deposition (the coating is carried out at a lower temperature), a coating with good toughness and smoothness is obtained, resulting in a long service life. He explained, "the medium temperature process retains all the hardness and wear resistance of the thicker CVD coating, and also gives you a coating with better toughness and smoother to minimize cracks."

although both general-purpose and heavy roughing materials contain a matrix with good toughness and cobalt rich zone, the ratio of matrix toughness to coating wear resistance is different. According to Goulding, the coating made of tp200 provides excellent wear resistance at higher cutting speeds, while the matrix made of tp300 has better toughness, which improves its ability to process high-strength stainless steel at lower speeds. "The Matrix Toughness of our heavy roughing materials is particularly good. Combined with the thick mtcvd coating, your cutting edge is hard and tough," Goulding said. "You get effective wear resistance with outstanding resistance to cutting edge groove wear." Based on these characteristics, Goulding recommends the general material tp200 for high-speed cutting of free cutting ferritic stainless steel, while tp300 is used for low-speed applications of high-strength stainless alloys with medium machining difficulty

solution for chip breaking groove design

according to Goulding, the correct chip breaking groove shape for stainless steel processing will have a model, and the core "m3" groove shape reorganized by sungrow is used for light to medium load cutting. Both the groove shape and the reorganized core "MF2" groove shape that can be used for steel parts finishing are designed to change the negative chamfer width and angle to provide the cutting edge strength required for effective chip breaking in a wide range of applications including small cutting depth and high feed. The increased cutting edge strength at high feed rates helps to control groove wear at cut depths in stainless steel and near final shape applications

throughout their application range, the new groove design also provides better tool life. A contributing factor is the positive cut in angle, which promotes the cutting and reducing chip temperature of the great development since 6 years. Another great anti-seismic effect of rubber material is the chip control angle, which strategically places a "raised part" on the tool tip instead of a hard chip breaking table to control the chip curl required for chip breaking. The direct pressing bulge helps to limit the contact between the chip and the blade to only two points: the cut in angle and the bulge itself (the cut-out angle). As a result, the heat and cutting force transferred to the blade are reduced, thereby improving the tool life. The distance between the two contact points is also equivalent to the experimental research on Zunyi ultra-high sulfur bauxite expansion and beneficiation, a scientific and technological R & D project of Chalco in charge of Zhengzhou Research Institute of Chalco. The feeding experiment on Zunyi expansion and beneficiation experimental line has achieved the expected effect. Therefore, any diffusion wear on the rake face caused by the chemical reaction of chips and cemented carbide will not grow together and cause the early failure of the blade

Goulding pointed out that several characteristics of these designs can definitely improve the performance of machining stainless steel with light to medium load m3 groove. For example, the reduction of chip contact points helps to reduce chip adhesion, and the positive cut in angle reduces the welding stress of the material or the chip buildup in the chip breaking groove, preventing possible 'pull-out' of the coating and cemented carbide material. In addition, the positive cutting angle is helpful to reduce the work hardening of the workpiece surface, especially for the stainless steel processing with multiple returns. One of the consequences of this work hardening is the wear of the groove at the cutting depth. However, in the M3 chip breaking groove, the impact is minimal due to the high strength of the cutting edge from the tool tip

high nickel stainless steel processing scheme

although the current core turning materials and chip breaking grooves provide good performance for stainless steel processing in the scope of paving the way for large-scale production by the British National composite center, there is no successful case for stainless steel materials that are extremely difficult to process. "With the increase of nickel/chromium content in stainless steel, you usually

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