New Development Status and Trends of CNC Tool New Technology

First, the status quo and development trend of new products of CNC tool materials

1 Overview:

In recent years, the results of basic research and new product development of CNC tool materials have been applied in high-speed (high-speed), hard (including heat-resistant, difficult-to-machine), dry, and fine (ultra-precision) CNC machining technologies. Development of new materials for cutting tool materials in superhard materials (diamonds, surface modified coating materials, TiC-based cermets, cubic boron nitride, Al2O3, Si3N4 based ceramics), W, Co coatings and fine particles (Super Fine-grained carbide bases and Go-type powder metallurgy high-speed steels have progressed rapidly.

2. Super hard material field:

Diamond (brazing polycrystalline, single crystal) types of tools have been rapidly applied to high-speed, high-efficiency, dry (wet) type of high hardness, high strength, difficult to process colored gold (alloy) and non-ferrous metal - non-metallic composite parts Mechanical cutting industry. The summary is as follows:

Automobiles and Motorcycles Industry: Polycrystalline, artificial single crystal diamond face milling cutters, boring knives, lathe tools, reamers, CNC tools such as composite (combination) hole machining are widely used in high-strength, high-hardness Si--Al alloys Parts automatic production line;

Bamboo flooring, furniture industry: Polycrystalline, CVD thick film deposition diamond (composite) end mills, three-edge forming cutters, face milling cutters and other types of tools are widely used in high-hardness composite bamboo flooring, furniture and doors and windows... Automatic production lines such as parts and components;

Aviation, aerospace, automotive and electronic information technology industries: Diamond CVD thin-film coating CNC tools (mainly WCo carbide-based tools are mainly used) Milling, turning, drilling, reaming and boring processing high-strength aluminum alloy (Casting, forging), fiber-metal laminates, carbon fiber thermoplastic composites, magnesium alloys, graphite, ceramics and other components, to meet the high-speed, high-life, dry machining technology requirements. Various manufacturers are constantly improving the diamond coating process technology to improve the bonding fastness and density of the diamond film and tool substrate;

Fine (Superfine) Machining Technology Field: Single-crystal natural and synthetic diamond tools used for precision (ultra-fine, nano-scale) turning of various workpieces such as precision instruments lenses, mirrors, computer disks, copiers (recorders) drums... Processing;

Single crystal diamond tools have also been used in ophthalmology corneal surgery fine cutting and printing board fine engraving ... and other industries.

Various manufacturers are continuously improving the grinding process technology, sharpening accuracy, and sharpening efficiency of all kinds of diamond tools.

The surface modification coating materials mainly include: TiN, TiCN, TiAlN, ALTiN, Al2O3, CrN, ZrC, MOS2, WS2, etc. The above-mentioned coating materials are used in opposition by computer-controlled PVD, PCVD, and CVD coating process technologies. Milling cutters, reamers, drills, composite (combined) hole machining tools, gear hobs, pinion cutters, shaving cutters, forming pull (pushing) knives, and surface modification coating treatments for various machined indexable inserts (The substrate is high-speed steel, WCo type cemented carbide, Ti-based cermet), to meet the high-speed, high-life cutting machining of high strength, high hardness cast iron (steel), forged steel, stainless steel, titanium alloy, nickel alloy, magnesium alloy, Aluminum alloys, powder metallurgy, bamboo and other materials require different production techniques. The tool surface modification coating process technology has the characteristics of greatly improving the cutting performance of the numerical control tool, and has the characteristics of low cost and quick effect. The process technology can change the coating material flexibly and flexibly according to various cutting processing technical requirements. excellent. Various manufacturers are continuously improving the coating process technology, improving the coating materials, and developing nano-multifunctional coating materials. The aim is to continuously improve the coating's fastness, wear resistance, impact toughness, etc., and try its best to expand the application range.

Ti-based cermets (TiCN series) various machine tools can be used to index turning tools, boring tools, reamers, milling cutters, compound (combined) hole machining CNC tools, and integral type (ball head) milling cutters, reamers, etc. CNC cutters are being used in high-strength, high-hardness cast iron (steel) alloys, forged steel alloys, hardened steel alloys, heat-resistant alloys, and powder metallurgy parts automatic production lines to meet high-speed, high-efficiency, hard, dry (wet) type Fine machining technology requirements. Various manufacturers are adopting different trace elements and sintering process technology to develop new metal ceramic material products in order to continuously improve its bending strength, impact toughness, and wear resistance. Japanese cermet tools have accounted for 30% to 40% of the total carbide tool. In the world, this type of tool application surface is also rapidly expanding.

Cubic boron nitride polycrystalline composite milling cutter (face milling cutter, corn milling cutter, ball end milling cutter), file, turning tool, reamer, composite (combined) hole machining and other numerical control tools (brazing, The machine clamp can be transposed in two structural forms. It is widely used in high-strength, high-hardness cast iron (steel) alloys, forged steel alloys, hardened steel alloys, powder metallurgy and other parts automatic production lines to meet the high speed, high efficiency, hard and fine Machining technical requirements.

Al2O3, Si3N4 based ceramics (whisker toughening) various machine tools can be used to index high-strength, high-hardness, wear-resistant cast iron (steel), forged steel, high manganese steel, etc. Quenched steel, powder metallurgy, engineering plastics, wear-resistant composite materials and other parts production lines, to meet the high-speed, high-efficiency, hard, dry machining technology requirements. At present, various manufacturers develop new types of medium and fine-grained ceramic materials and functionally graded (multi-phase) ceramic materials by adding different trace elements and innovative production technology to Al2O3 and Si3N4 based ceramic materials in order to continuously improve their bending strength. , Impact toughness.

3, W, Co coating and fine particles (ultrafine particles) carbide material City:

W, Co fine (medium) particle cemented carbide substrate material to meet a variety of surface modification coating material coating process technology requirements to add a variety of trace elements, to meet a variety of machining technology for the indexable blade cutting The development of performance requirements; development and application of ultra-fine particle cemented carbide substrate materials in two aspects: in the electronics, information technology industry for the processing of fiber-metal composite laminate materials micro drill bit, end mill, its matrix The material develops in the direction of high toughness, and the surface is coated with a diamond film to increase the hardness and wear resistance of the tool surface; in the manufacturing industries such as the mold industry, aircraft, steam turbines, automobiles, etc., for the machining of high-strength, high-hardness cast iron (steel), Forged steel, aluminum alloy (cast, forging), powder metallurgy material workpiece integral type (ball head) milling cutter, special extrusion tool, reamer (Φ30mm <diameter> Φ4mm), drill, composite (combined) hole processing tool ... and other numerically-controlled cutters, whose base materials develop toward high hardness and high toughness. Generally not coated, used repeatedly regrind.

4, including Co class powder metallurgy high-speed steel material city:

To develop powder-metallurgy high-speed steel (including Co-type) materials for innovative milling, hot-pressing, and trace element innovation, and to make all kinds of forming broaches (monolithic, modular), high-speed hobs, and shaved (insert) cutters. , taps, corrugated edge end mills, forming end mills and rolling (squeezing, roller compaction) pressure tools are widely used in manufacturing industries such as cars, motorcycles, aero engines, steam turbines, etc. to process high strength, high hardness cast iron (steel ) Alloy, alloy structural steel (forging), heat-resistant alloy steel, stainless steel, monolithic aluminum alloy (hot forging), and high Si--Al alloy material workpieces. According to the different requirements of cutting technology, the surface is coated with coating materials such as TiN, TiCN, TiALN, CrN, MoS2, ZrC, etc. to meet the high-speed, high-efficiency and hard-precision machining technology requirements.

CNC tool materials are the more active material science and technology city. The introduction of each new product will make machining technology a new level. Each manufacturer has always attached great importance to the R&D technology of the city.

Second, the new structure of the CNC tool, new varieties of science and technology development status and trends

1 Overview:

In recent years, the scientific and technological achievements of CNC cutters are mainly reflected in the development of a multi-cutting function and improved cutting performance of the cutting edge. They are adaptable to high speed (ultra-high speed), hard (including heat and difficult processing), dry, and fine (ultra-fine). Cutting and high efficiency CNC machining cutting technology requirements. With the advancement of part blank manufacturing technology, the precision of part blank geometry and cutting allowance is controlled. The research and development of the new structure and new varieties of CNC cutting tools are mainly concentrated in the light and medium load cutting ranges, and special hole machining, broaching and rolling are used. (Crushing, Rolling) The five types of cutting tools such as pressing, milling and turning are more active in the development and they are supporting the development of their corresponding chip breaker groove shapes.

2, CNC tool system:

In recent years, there has been an international trend to replace the various tool systems developed by various manufacturers with the "HSK" tool system. The developed countries in Europe use the HSK tool system standard of German DIN69893-1, and the International Standardization Organization Committee has developed the ISO/DIS standard for it. The HSK tool system has features such as high dynamic and static stiffness, good positioning (turning) accuracy, and high allowable rotation speed (≤150000p.rm). It is not only easy to regulate tool management, but also saves overall tool costs and reduces production costs. It was first applied to machining centers, CNC boring and milling machines, and gradually expanded to all types of lathes (turning centers), grinding machines (grinding centers), CNC special-purpose machines, and automatic CNC machining lines. The application range covers almost all tooling fields.

3, hole processing tools:

In the tool door category, the hole machining tools are a large family, and their small changes are endless. Here, the major new structures and new varieties are briefly described as follows:

CNC drill:

Integral drill: The cutting edge of the drill tip is changed from a symmetrical straight type to a symmetrical circular type (r=1/2D) to increase the cutting edge and increase the life of the drill tip; the core is thickened to increase the rigidity of the drill body. "The type chisel edge (or spiral center edge) replaces the traditional chisel edge to reduce the axial drilling resistance and improve the life of the traverse edge; different step angle drill tips and negative rakes are used to improve the performance of chip separation, chip breaking, and drilling And hole processing accuracy; mosaic modular hard (super hard) material crown; oil hole cooling and large spiral angle (≤ 40 °) structure. Recently, monolithic ceramics (Si3N4) and Ti-based cermet materials have been developed.

Machine-clamping drill: The drill tip adopts a special symmetrical cutting edge with a rectangular shape and an indexable blade with self-balancing radial force to replace the other geometries. Small drilling vibration improves self-centering performance, life and hole machining accuracy.

● Composite (combined) hole machining CNC tool:

The new structure and new technology of the drill bit, reamer, expanding knife and extrusion tool are integrated, and the integrated, machine-clamped and special compound (combined) hole machining CNC tool development is very fast. In general, the current development trend is the use of embedded module-type hard (ultra-hard) material cutting edges (including crowns) and oil hole cooling, large spiral grooves and other structures.

● CNC reamer:

Large spiral angle (≤ 45 °) cutting edge, non-edge extrusion reaming and oil hole cooling structure is the overall development direction, the maximum reaming diameter has reached φ ≤ 400mm.

● Files:

Single-edge fine-tuning precision boring burrs are being replaced by multi-edged boring cutters, reamers, and special (combined) hole-machining CNC tools. Developed in foreign countries to use the tool system internal push-pull rod axial movement or high-speed centrifugal belt balance slider movement, one pass to complete the cutting of the spherical surface (curved surface), bevel and reverse cutting the back of the cutting part of the CNC intelligent precision boring tool, representative The sickle development direction.

● Tap:

Developed a large spiral angle (≤ 45°) tap, the cutting cone depending on the soft and hard condition of the machined parts, designing special blade angles, rake angles, etc.

● Expand (hole) hole cutter:

Multi-blade, configuration of various CNC tool shanks and modular adjustable micro tool holders are the development direction of the current (扩) hole cutters.

4, CNC milling cutters:

Integral type end mills: The side edge of the carbide end mill adopts a large helix angle (≤62°) structure. The over center end edge of the end of the end mill cutter often has an arc (or spiral center edge) shape and a negative edge. Dip angle, increase the length of the cutting edge, improve the stability of the cutting, the accuracy of the workpiece table and tool life. Adapt to the requirements of CNC high speed and stable three-dimensional space milling processing technology.

Clamp end mills: Side teeth, end teeth and over center edge end teeth (all short) combined by indexable inserts (usually provided with three-dimensional chip-breaker geometry) The cutting edge can meet the technical requirements for CNC high-speed and stable three-dimensional space milling.

CNC milling cutters have adopted computer-aided design, cutting simulation simulation and CNC machining technology forming and manufacturing.

Machine-clamp CNC face milling cutter: The cutter body tends to be made of lightweight high-strength aluminum and magnesium alloys. The cutting edge adopts a large rake angle and a negative blade inclination angle. The indexable insert (geometric shape) has a three-dimensional chipbreaker shape.

CNC milling cutters and special compound hole machining tools have applied high-speed rotary body dynamic balancing and safety clamping technology. Some high-speed rotary cutters also apply aerodynamic principles, using cyclonic cold cutting edges, during dry cutting machining. Reduce cutting edge temperature and increase tool life.

5, turning tool,

Grooving and cutting type turning tools have developed a multi-function turning tool for collecting the end surfaces of the vehicle, outer garden, profiling, grooving, cutting, and chamfering. The insert clamping method adopts an inlaid elastic knife body, and the cutting force is self-fixed. The structure is very suitable and novel.

6, broaching tools:

Under the support of modern CNC machining technology, we have developed a variety of special external contour precision forming, combined broach and car-pull combination forming broaching tools, together with special CNC machine tools. The batch production efficiency of parts of automobiles is increased by several times, and the product quality and accuracy are very stable.

7, other tools:

The small-volume involute gears and spline shaft parts batch production process for automobiles and motorcycles adopts rolling, squeezing, and chipless processing technology, and develops special tools and special numerical control machine tools to enable the batch production of specific workpieces. The efficiency is increased by several times, and the quality and accuracy are very stable.

Third, the conclusion

The innovations of broaching, rolling, squeezing tools and compound (combined) hole machining CNC tools often cause a tremendous change in the concept of machining, and then integrate the cutting-edge technology of cutting tool materials and special CNC machine tools. The benefits and economic benefits are also enormous.