Development and Application of Modern Shanghai Blade Cutting Technology

As the main basic technology of manufacturing technology, cutting processing is the main processing technology of the automotive industry, aerospace industry, energy industry, military industry and emerging mold industry, electronics industry and other departments. It is also an important factor for the rapid development of these industrial sectors.

Although near net forming technology and stack forming technology are very promising new processes, the status of cutting processing as the main basic process of manufacturing technology has not changed. On the contrary, cutting technology has entered a new era of rapid development - modern cutting technology. Therefore, understanding and mastering the development mechanism of modern cutting technology, understanding its technical characteristics and development trends, and how to apply modern cutting technology to improve processing efficiency is an important topic in the current mechanical processing industry.

1. Development mechanism of modern cutting technology

Machining has become a professional technology that began in the late 19th and early 20th centuries and has gone through a whole century. After the advent of self-cutting technology, it played an important role and made important contributions to the industrialization and economic development of industrialized countries. Although the cutting technology itself has made great progress in this process, it did not go beyond the traditional cutting technology in the 1970s. The most prominent marks are the development and production of tools and the use of tools. And the users are basically separated from each other, and there is no mechanism for mutual promotion and common development.

Due to the rapid development of emerging science and technology such as computers and microelectronics, and the rapid development of materials science closely related to cutting technology, cutting technology has developed rapidly with the development of manufacturing and manufacturing technology, and has entered a new stage of modern cutting technology. Compared with traditional cutting technology, modern cutting technology not only reflects faster cutting speed and higher processing efficiency, but also forms a new development mechanism and becomes an important technical factor driving the development of manufacturing and modern manufacturing technology.

In the long period after the advent of cutting technology, there was a problem that plagued the tool industry and tool users. That is, if you use a more expensive tool for cutting, it can increase the cutting efficiency, but it will increase the manufacturing cost. The user thinks that it is not worth the candle. Therefore, many users are reluctant to spend more money to buy good tools, or after buying a good knife, they are worried that the tool will be used quickly and the tool life will be long. These concepts and practices hinder the renewal of tools, affect the enthusiasm of tool manufacturers to develop new tools, and limit the improvement of cutting efficiency and the advancement of cutting technology.

It turns out that when using a good tool, if you don't pay attention to improving the cutting efficiency and just pursue to extend the tool life, you can only receive very limited results for reducing the manufacturing cost, and may even be counterproductive. The intrinsic link between improving cutting technology and creating considerable benefits for users and society has been recognized and accepted by more and more tool manufacturers and tool users, and has been transformed into a powerful driving force for cutting technology advancement in just 20 years. In the meantime, cutting technology has been pushed to a new stage in modern cutting technology.

The development mechanism of modern cutting technology can be summarized as follows: On the one hand, improving the cutting efficiency instead of concentrating on the benefits brought by the tool life gives the tool manufacturers great encouragement, and accordingly establishes “innovative processes, innovative tools, and improved cutting efficiency. The new business philosophy of "serving the user" has injected new vitality into the cutting of traditional manufacturing technology, making tool manufacturers the main force in the development of modern cutting technology; on the other hand, this concept has also been more and more Accepted by tool users, it has formed a new thinking of “actively adopting new cutting technology, applying advanced cutting tools to improve processing efficiency, reducing manufacturing costs and improving enterprise competitiveness”, making the manufacturing industry pay more attention to and demand for advanced tools. The degree has become a powerful force for the rapid development of cutting technology. This “pull” is not a simple acceleration of the development of cutting technology, but gives the cutting mechanism a new development mechanism and power to make it transition from traditional cutting technology using disjointed to modern cutting with user demand and use. A new phase of technology.

2. Technical characteristics and development trends of modern cutting technology

Cutting machining has entered a new stage of modern cutting technology, not only reflected in the development of cutting technology based on the mechanism of tool manufacturer and tool user linkage, but also shows the following obvious technical features and development trends.

(1) New cutting technology breaks through traditional cutting technology

New technologies such as high-speed, high-efficiency cutting, hard cutting, and dry cutting are used in the “big family” of cutting, such as automotive, aerospace, mold, and equipment manufacturing, which not only doubles the processing efficiency, but also promotes product development and process innovation. In recent years, the fast-developing mold industry can be said to grow together with high-efficiency mold cutting processes. Large-scale mold high-speed milling and hardened mold milling processes have changed the traditional mold processing technology and greatly shortened the mold development cycle.

At the same time, the boundaries of traditional cutting processes such as turning, milling and drilling have been continuously broken, and some new cutting methods have emerged. For example, the newly introduced milling cutter can be used as a hole machining tool for drilling and reaming, which reduces the tool change time and improves the machining efficiency. For example, it can efficiently remove the cavity metal inserting cutter and machine the crankshaft. In the compound turning center, the milling process of the milling machine, the carbide high-speed machining process using the carbide thread milling cutter instead of the hard alloy tap. In addition, with the development of various composite machine tools and the "one machine or one-time complete machining" technology, the traditional technology of cutting processing will be further changed.

(2) Significant progress in tool materials and coating technology

The new cutting technology has completely broken through the traditional cutting technology thanks to the improvement of tool materials and the development of coating technology.

The development of tool materials is reflected in the overall improvement of the performance of various tool materials, which has improved the processing efficiency in all fields of cutting. Among them, special emphasis is placed on the advancement of two tool materials, namely the advancement of superhard tool materials PCD, CBN and cemented carbide materials.

PCD and CBN materials have high hardness and particularly good wear resistance. They have been hoped to become the promoters of high-speed cutting, but due to their brittleness, their practical process has been slow for a long time after the advent. In recent years, through the control and adjustment of PCD, CBN material manufacturing process, formulation composition, tissue size and other factors, the material toughness has been significantly improved, the variety has increased, and the application field has expanded, making the hope of applying superhard tool materials for high-speed cutting become The reality.

As a tool material, cemented carbide has always been a contradiction between hardness and toughness. Although its application in cutting operations such as turning, milling, and hole machining has played an important role in improving machining efficiency over the years, its poor toughness has not been significantly improved. Nowadays, solid carbide drills and end mills made of ultra-fine grained carbide have been widely used, and the cutting speed can be increased several times than that of high-speed steel tools, making cemented carbide the most widely used and comprehensive performance. The best tool material. Another major advancement in cemented carbide materials is the development of gradient cemented carbide materials that make the surface of the coated carbide inserts rich in cobalt, which improves the toughness of the carbide insert edges, not only reduces chipping, but also The use of a base material resistant to plastic deformation improves the bearing capacity of the insert and significantly improves the cutting performance of the coated cemented carbide insert.

Significant progress has been made in coating technology for the past 10 years. In the field of CVD coatings, medium temperature CVD TICN and thick film AL2O3 coatings improve the wear resistance and crack propagation resistance of the insert. The development of PVD coatings is particularly striking, not only the wear resistant coatings such as TIALN, ALTIN, ALCRN, TISIN, AL2O3, but also various lubricating coatings such as MOS2, DLC, WC/C, as well as gradient coatings and nano-coatings. New coating structures such as coatings greatly improve the performance of the coating. At present, the development trend of coating technology is in the ascendant. With its many functions, good effects and rapid development, it has become the most effective means to improve cutting performance.

(3) The speed of innovation in new grades and new products is greatly accelerated

As a tool, tools are the most dynamic process factor in a manufacturing system and are in the process of continuous innovation.

In the modern cutting technology stage, the development of the tool has two major characteristics: First, the speed of innovation is accelerating. The biennial Beijing International Machine Tool Show (CIMT) has become a "new product launch" for tool manufacturers around the world, new material grades, new coated products, new tool (sheet) structures, new tool holders. And clamping technology, new processing methods, and so on. The second is to establish innovative ideas for system optimization. On the basis of system optimization, the newly developed coated hard alloy grades can often increase the cutting efficiency by more than 20% compared with the original grades, and some can even reach more than 50%. A new tool product can provide a new processing effect, or significantly improve the processing efficiency, such as the popular large-feed milling cutter in recent years, the feed per tooth reaches 3.5~4.0MM/Z, which is the general milling cutter. 10 times; another example, the amount of feed for a shaved turning insert can be doubled.

(4) The connotation of modern cutting technology

After the cutting process entered a new stage of modern cutting technology, many new related technologies appeared, which expanded the connotation of cutting technology. For example, high-speed cutting technology was first applied to rotating tools, mainly milling. In the early days, the spindle speed exceeded 10000R/MIN as the threshold for high-speed cutting. Around this goal, the technology related to the machining center was developed including high-speed spindle and fast. Feed, high plus (minus) speed technology and CNC systems for high-speed cutting; developed tool-related technologies including HSK tool holders, 7:24 two-sided contact holders, safety technology for high-speed rotary tools and tool balancing technology. In order to use high-speed machining of solid carbide universal tools, it is necessary to improve the accuracy and rigidity of tool clamping. New hydraulic chucks and tooling adjustment technologies such as hydraulic chucks, hot chucks and force shrink chucks have been developed. In addition, in order to improve tool utilization and reduce tool management costs, tools such as tool management software and cutting database have been developed to improve the overall level of cutting processing with modern information technology.

3. How to apply modern cutting technology to improve processing efficiency

At present, the development situation of the mechanical cutting industry is very good. So, how to apply modern cutting technology to improve the processing efficiency of enterprises? You can start from the following aspects:

(1) Improve tool material properties and develop coating technology

An important symbol of the rapid development of cutting technology in recent years is the continuous improvement of the performance of tool materials and the rapid advancement of coating technology, especially the large-scale cemented carbide materials and their turning and milling inserts. The newly developed carbide inserts of various tool companies are springing up, and their varieties cover all fields of cutting and processing. Usually the introduction of a new grade can increase cutting efficiency by 20% to 30%, and some even up to 100%. Therefore, a comprehensive review of the old materials used by the company for a long time, the elimination of some of the old brands, the use of the corresponding new materials, new grades, especially the use of coated grades instead of uncoated grades, can improve the processing efficiency can receive immediate results.

(2) Development of new tool structures

Rapid development of new tool structures plays an important role in improving machining efficiency. For example, Sandvik Coromant's new CORODRILL880 carbide indexable shallow hole drill can improve the feed rate or cutting speed compared with the original shallow hole drill due to the significant improvement in the structure of the tool (sheet). Nearly double, the processing efficiency can be increased by about 70%, and better processing accuracy and surface quality can be obtained. Another example is the Harbin Steam Turbine Works, which encountered the problem of large-diameter deep hole machining when it produced the first 600,000 KW supercritical steam turbine in China. If it is processed with traditional hole machining tools, each hole should be 6.7H, and the machining task cannot be completed. . Later, the plant used a composite drill from Kennametal. The processing time per hole was only 0.5H, which reduced the processing time by about 93%. The original 40D (days) did not complete the processing of about 200 deep holes, 5D. It’s all done. It can be seen that enterprises should actively use abundant advanced tool resources to improve processing efficiency or solve the processing problems encountered in production, and use this as an opportunity to continuously improve the application level of cutting technology and tools.

(3) Development and adoption of new tools

In recent years, the tool industry has developed new tools for certain machinery industries, which have the characteristics of high efficiency or innovative technology, and play an important role in promoting the progress of processing technology in the industry. For example, the insert milling (drill) knife, multi-function milling cutter, large feed milling cutter, horn milling cutter and other tools developed for the mold industry have played an important role in improving mold processing efficiency and innovating mold processing technology. Therefore, enterprises should keep abreast of and collect the latest developments of the industry's cutting tools, and use them for us to maintain the advanced cutting processing level and leading processing efficiency.

In addition, cutting technology has some common results, such as indexable tools instead of welding knives, squeezing blades and spiral-blade inserts with horns, and other integral indexable inserts that can replace general-purpose high-speed steel knives. Alloy drills, end mills and other tools, these tools have a general effect on the processing efficiency of a large number of large-scale car, milling and drilling processes, and have long been proved by production practice. However, the unavoidable fact is that there are still quite a few enterprises that have not fully adopted this part of technology for various reasons, and have been using tools that have long since fallen behind, thus restricting the development of enterprises for a long time. Companies should plan to use common advanced cutting technology and tools to quickly change the appearance of the tool.

China is a country with relatively backward cutting technology. Existing technologies and products have not been able to meet the demand for advanced tools in important industrial sectors of manufacturing. Therefore, accelerating the development of cutting technology and mastering the core technology of modern cutting is not only of great practical significance but also increasingly urgent for China's historical task of building and manufacturing a strong country and completing new industrialization, and realizing the goal of revitalizing the equipment manufacturing industry.