Since its invention in Europe in the 1920s, fine blanking technology has a history of more than 80 years. As one of the important precision plastic forming methods in the field of heavy plate manufacturing, it is a high-tech and cost-effective solution for the mass production of high-quality, multi-functional ferrous and non-ferrous metal parts.
A fine blanking press completes one stroke; through processing with a special fine blanking die, one or more high-precision formed parts ready for direct assembly are produced. It has been widely used in electronics, computers, electric power, home appliances, automotive, aviation and other fields.
According to incomplete statistics, fine blanking technology has been adopted in about 40 countries worldwide, with approximately 4,500 fine blanking machines in operation, producing about 10,000 types of parts. For example, a passenger car contains nearly 100 types of fine blanked parts, including transmission shift forks, seat and seatbelt adjusters, planetary gears, brake shoes and steel backs.
During the 11th Five-Year Plan period, China’s fine blanking die technology made considerable progress, and a series of scientific research achievements were obtained in fine blanking processes, materials, presses, die sets, dies and lubrication.
By the end of 2008, nearly 20 provinces and cities in China were equipped with professional fine blanking production equipment, with more than 80 fine blanking presses (excluding hydraulic die sets), over 5,000 employees in the fine blanking industry, about 2,000 types of fine blanked parts produced, and several demonstration bases for independent fine blanking die development established.
Metal blanking has expanded from non-ferrous metals to ferrous metals. The blanking thickness of low-carbon steel, low-alloy steel and stainless steel has reached 12 mm; for non-ferrous metals such as aluminum alloy and copper alloy, it has reached 18 mm.
With advances in die materials and treatment methods, as well as the improvement and popularization of spheroidizing treatment for blanks, some harder high-carbon steels, high-alloy steels and other low-toughness materials such as nickel-based or cobalt-based alloys have also begun to be used for fine blanked parts.
In addition, the proportion of independently developed progressive compound fine blanking dies, transfer dies and modular dies in domestic fine blanking dies has increased significantly. In particular, progressive compound fine blanking dies for complex parts for automotive transmission systems have been basically localized.
Research, development and application of finite element numerical simulation for fine blanking processes, die structure optimization, intelligent design and knowledge base technology have enhanced and enriched the technical connotation of China’s fine blanking dies.
However, domestic fine blanking enterprises generally face problems such as small scale, scattered resources, low production efficiency, talent shortage and incomplete supporting systems.
Although certain development capabilities have been formed in fine blanking die design, there is still a lack of experience in the development of complex fine blanking dies, especially compound forming dies, and imported dies still account for a large share.
Overall, there is still a gap between China’s fine blanking technology and die levels and those of other countries (such as Switzerland). For instance, the application of fine blanking in manufacturing is not sufficiently widespread.
Larger gaps exist in systematic design and manufacturing theories, supporting equipment, fine blanking oil, processes and measuring instruments. Fine blanking is a die technology that needs vigorous promotion and development.
Main Gaps Compared with International Levels
1. Fine Blanking Die Life
The main gap between domestic and overseas precision blanking dies lies in shorter service life.
Overseas fine blanking dies typically achieve a grinding life of more than 40,000 strokes for common steel materials, with total die life exceeding hundreds of thousands of strokes. Domestic dies only reach about 50% of the overseas level. The prominent issues affecting die life are die material quality and heat treatment. Due to the high cost of imported die steel, most domestic dies still use domestic die steel for medium‑low volume production.
Poor material quality, plus unstable control and quality in forging and heat treatment processes, result in large differences in overall die life.
2. Fine Blanking Materials
Fine blanking material is one of the core elements of fine blanking technology, requiring uniform structure and moderate hardness. Spheroidizing annealing is required before blanking, with a spheroidization rate above 95%.
Most domestic materials can hardly meet this requirement, with spheroidization rates only between 50% and 90%.
For die materials, current grades can basically meet fine blanking requirements in shearing, but cannot simultaneously satisfy high strength and high toughness for extrusion forming. The performance (chemical composition, mechanical properties) and tolerances of domestic fine blanking metal sheets are inferior to imported materials. In addition, material order volumes often fail to meet steel mills’ minimum batch requirements, forcing enterprises to purchase at high prices or rely on long-term imports. These factors increase the cost of fine blanked parts, leading many enterprises to substitute with ordinary sheets or simplified fine blanking, restricting market development.
Furthermore, overseas research has advanced from conventional materials to high-strength fine blanking materials with tensile strength up to 900 N/mm², making fine blanking of high-hardness materials feasible.
3. Fine Blanking Die Design
Internationally, progressive fine blanking dies dominate, accounting for more than 70%, with production efficiency as high as 100 parts per minute and near-zero defect quality. China currently has certain capabilities in fine blanking die design and development. However, the domestic industry still lacks experience in designing and developing complex fine blanking dies, especially compound forming dies. Although some enterprises have accumulated expertise for specific products, a considerable overall gap remains. The domestic self-sufficiency rate is less than 80%, with oversupply in low- and medium-grade dies and a self-sufficiency rate below 60% for high-grade dies.
In addition, domestic die life is generally only one-third of the international level, due to factors including die design, blanking materials, die materials, manufacturing precision, press precision, lubricants and process systematics.
4. Fine Blanking Die Manufacturing
Internationally, extensive know-how has been accumulated in fine blanking die manufacturing processes, especially in century-old enterprises with expert-level technical reserves. Domestic accumulation of proprietary fine blanking die technology is limited, and much progress is still needed. Moreover, die surface quality is critical to performance and service life, especially for complex, high-precision fine blanked parts for high-end passenger car drive and transmission systems. Although domestic attention has been paid to surface treatment technology for die cavities, an obvious gap still exists compared with foreign countries.
5. Stamping Analysis Capability in Die Design
Overseas research on finite element numerical simulation for fine blanking and stress analysis simulation and verification for dies has reached a high level, and has been applied to design verification, structural optimization and other aspects. Although some domestic universities and research institutes have conducted basic research in this field, gaps remain in applied research.
6. Basic Research Team
Since its emergence, fine blanking has attracted academic attention due to its unique plastic forming characteristics.
Currently, some universities and institutes maintain relatively in-depth research on fine blanking processes and die technology, but a considerable gap still exists compared with international levels. Internationally, the University Alliance for Fine Blanking Research promoted by Switzerland’s FEINTOOL combines five research institutions: ETH Zurich (Virtual Manufacturing Technology), RWTH Aachen (Machine Tools), TUM Munich (Metal Forming and Casting), Ohio State University (OSU) and Shanghai Jiao Tong University. It is one of the most active academic teams in fine blanking technology.
7. Die Standardization
The common international standard related to fine blanking dies is the German Engineers Association standard VDI 3345 (Feinschneiden). Foreign fine blanking enterprises such as Switzerland’s FEINTOOL (a main drafter of VDI 3345) have established corporate standards based on VDI 3345, some of which are public. At present, major Chinese fine blanking enterprises formulate relevant standards based on VDI 3345 and FEINTOOL’s corporate standards.
To improve the overall capacity of China’s fine blanking die industry and promote standardized development, it is particularly important to formulate national or industrial standards for fine blanking dies in China by integrating international standards and domestic industrial conditions.
8. Fine Blanking Equipment
Foreign fine blanking equipment has developed synchronously with the technology for decades. Switzerland’s FEINTOOL, in particular, has been at the forefront, with world-leading equipment, technology, accessories and fine blanking oil. In recent years, Japanese fine blanking equipment has gradually emerged and captured a large share of the mid-range market, while China is still almost blank in this regard.
Future Development Goals and Major Tasks
China’s future development goal for fine blanking dies is to meet domestic market demand for fine blanked parts, start with the design and manufacturing of progressive fine blanking dies, expand industrial scale and production capacity, make remarkable progress in independent development of complex fine blanking dies, digital die research, die material development and rational application, and surface treatment technology.
Efforts will be made to improve the technical level of enterprises, narrow the gap with international standards, and achieve wider application of domestic fine blanked parts.
Priorities and Major Topics for Future Product and Technology Development
1. Research on Key Technologies for Design and Manufacturing of Progressive Fine Blanking Dies for Complex Parts
Progressive fine blanking dies for complex parts represent cutting-edge basic technology in fine blanking. Research in this field is expected to drive a significant upgrade of China’s overall fine blanking technology.
Taking progressive fine blanking dies for complex parts such as synchronizer rings, clutch plates and longitudinal composite progressive fine blanking processes and dies as breakthroughs, research will focus on key design and manufacturing technologies to rapidly upgrade domestic fine blanking die technology and narrow the gap with developed countries as soon as possible.
2. Research on Life Improvement of Fine Blanking Dies and Related Key Technologies
Die life is a comprehensive reflection of the level of die materials, processes and supporting products.
Carrying out technical research focused on fine blanking die life can not only solve the urgent problem of excessively short die life in China, but also promote technological development of die materials, fine blanking processes, supporting tooling and auxiliary products.
3. Research and Development of Combined Fine Blanking and Precision Forging Technology
Fine blanking and precision forging are two parallel manufacturing technologies.
Workpieces too thick for fine blanking require precision forging, while those too thin for precision forging must be fine-blanked; the two are closely interrelated.
The basic idea of developing a combined process is to identify integration points, such as gear parts with hubs and cam parts with short shafts.
China has a long history and high level in precision forging, which provides an effective path to提升 the overall level of domestic fine blanking technology.
A fine blanking press completes one stroke; through processing with a special fine blanking die, one or more high-precision formed parts ready for direct assembly are produced. It has been widely used in electronics, computers, electric power, home appliances, automotive, aviation and other fields.
According to incomplete statistics, fine blanking technology has been adopted in about 40 countries worldwide, with approximately 4,500 fine blanking machines in operation, producing about 10,000 types of parts. For example, a passenger car contains nearly 100 types of fine blanked parts, including transmission shift forks, seat and seatbelt adjusters, planetary gears, brake shoes and steel backs.
During the 11th Five-Year Plan period, China’s fine blanking die technology made considerable progress, and a series of scientific research achievements were obtained in fine blanking processes, materials, presses, die sets, dies and lubrication.
By the end of 2008, nearly 20 provinces and cities in China were equipped with professional fine blanking production equipment, with more than 80 fine blanking presses (excluding hydraulic die sets), over 5,000 employees in the fine blanking industry, about 2,000 types of fine blanked parts produced, and several demonstration bases for independent fine blanking die development established.
Metal blanking has expanded from non-ferrous metals to ferrous metals. The blanking thickness of low-carbon steel, low-alloy steel and stainless steel has reached 12 mm; for non-ferrous metals such as aluminum alloy and copper alloy, it has reached 18 mm.
With advances in die materials and treatment methods, as well as the improvement and popularization of spheroidizing treatment for blanks, some harder high-carbon steels, high-alloy steels and other low-toughness materials such as nickel-based or cobalt-based alloys have also begun to be used for fine blanked parts.
In addition, the proportion of independently developed progressive compound fine blanking dies, transfer dies and modular dies in domestic fine blanking dies has increased significantly. In particular, progressive compound fine blanking dies for complex parts for automotive transmission systems have been basically localized.
Research, development and application of finite element numerical simulation for fine blanking processes, die structure optimization, intelligent design and knowledge base technology have enhanced and enriched the technical connotation of China’s fine blanking dies.
However, domestic fine blanking enterprises generally face problems such as small scale, scattered resources, low production efficiency, talent shortage and incomplete supporting systems.
Although certain development capabilities have been formed in fine blanking die design, there is still a lack of experience in the development of complex fine blanking dies, especially compound forming dies, and imported dies still account for a large share.
Overall, there is still a gap between China’s fine blanking technology and die levels and those of other countries (such as Switzerland). For instance, the application of fine blanking in manufacturing is not sufficiently widespread.
Larger gaps exist in systematic design and manufacturing theories, supporting equipment, fine blanking oil, processes and measuring instruments. Fine blanking is a die technology that needs vigorous promotion and development.
Main Gaps Compared with International Levels
1. Fine Blanking Die Life
The main gap between domestic and overseas precision blanking dies lies in shorter service life.
Overseas fine blanking dies typically achieve a grinding life of more than 40,000 strokes for common steel materials, with total die life exceeding hundreds of thousands of strokes. Domestic dies only reach about 50% of the overseas level. The prominent issues affecting die life are die material quality and heat treatment. Due to the high cost of imported die steel, most domestic dies still use domestic die steel for medium‑low volume production.
Poor material quality, plus unstable control and quality in forging and heat treatment processes, result in large differences in overall die life.
2. Fine Blanking Materials
Fine blanking material is one of the core elements of fine blanking technology, requiring uniform structure and moderate hardness. Spheroidizing annealing is required before blanking, with a spheroidization rate above 95%.
Most domestic materials can hardly meet this requirement, with spheroidization rates only between 50% and 90%.
For die materials, current grades can basically meet fine blanking requirements in shearing, but cannot simultaneously satisfy high strength and high toughness for extrusion forming. The performance (chemical composition, mechanical properties) and tolerances of domestic fine blanking metal sheets are inferior to imported materials. In addition, material order volumes often fail to meet steel mills’ minimum batch requirements, forcing enterprises to purchase at high prices or rely on long-term imports. These factors increase the cost of fine blanked parts, leading many enterprises to substitute with ordinary sheets or simplified fine blanking, restricting market development.
Furthermore, overseas research has advanced from conventional materials to high-strength fine blanking materials with tensile strength up to 900 N/mm², making fine blanking of high-hardness materials feasible.
3. Fine Blanking Die Design
Internationally, progressive fine blanking dies dominate, accounting for more than 70%, with production efficiency as high as 100 parts per minute and near-zero defect quality. China currently has certain capabilities in fine blanking die design and development. However, the domestic industry still lacks experience in designing and developing complex fine blanking dies, especially compound forming dies. Although some enterprises have accumulated expertise for specific products, a considerable overall gap remains. The domestic self-sufficiency rate is less than 80%, with oversupply in low- and medium-grade dies and a self-sufficiency rate below 60% for high-grade dies.
In addition, domestic die life is generally only one-third of the international level, due to factors including die design, blanking materials, die materials, manufacturing precision, press precision, lubricants and process systematics.
4. Fine Blanking Die Manufacturing
Internationally, extensive know-how has been accumulated in fine blanking die manufacturing processes, especially in century-old enterprises with expert-level technical reserves. Domestic accumulation of proprietary fine blanking die technology is limited, and much progress is still needed. Moreover, die surface quality is critical to performance and service life, especially for complex, high-precision fine blanked parts for high-end passenger car drive and transmission systems. Although domestic attention has been paid to surface treatment technology for die cavities, an obvious gap still exists compared with foreign countries.
5. Stamping Analysis Capability in Die Design
Overseas research on finite element numerical simulation for fine blanking and stress analysis simulation and verification for dies has reached a high level, and has been applied to design verification, structural optimization and other aspects. Although some domestic universities and research institutes have conducted basic research in this field, gaps remain in applied research.
6. Basic Research Team
Since its emergence, fine blanking has attracted academic attention due to its unique plastic forming characteristics.
Currently, some universities and institutes maintain relatively in-depth research on fine blanking processes and die technology, but a considerable gap still exists compared with international levels. Internationally, the University Alliance for Fine Blanking Research promoted by Switzerland’s FEINTOOL combines five research institutions: ETH Zurich (Virtual Manufacturing Technology), RWTH Aachen (Machine Tools), TUM Munich (Metal Forming and Casting), Ohio State University (OSU) and Shanghai Jiao Tong University. It is one of the most active academic teams in fine blanking technology.
7. Die Standardization
The common international standard related to fine blanking dies is the German Engineers Association standard VDI 3345 (Feinschneiden). Foreign fine blanking enterprises such as Switzerland’s FEINTOOL (a main drafter of VDI 3345) have established corporate standards based on VDI 3345, some of which are public. At present, major Chinese fine blanking enterprises formulate relevant standards based on VDI 3345 and FEINTOOL’s corporate standards.
To improve the overall capacity of China’s fine blanking die industry and promote standardized development, it is particularly important to formulate national or industrial standards for fine blanking dies in China by integrating international standards and domestic industrial conditions.
8. Fine Blanking Equipment
Foreign fine blanking equipment has developed synchronously with the technology for decades. Switzerland’s FEINTOOL, in particular, has been at the forefront, with world-leading equipment, technology, accessories and fine blanking oil. In recent years, Japanese fine blanking equipment has gradually emerged and captured a large share of the mid-range market, while China is still almost blank in this regard.
Future Development Goals and Major Tasks
China’s future development goal for fine blanking dies is to meet domestic market demand for fine blanked parts, start with the design and manufacturing of progressive fine blanking dies, expand industrial scale and production capacity, make remarkable progress in independent development of complex fine blanking dies, digital die research, die material development and rational application, and surface treatment technology.
Efforts will be made to improve the technical level of enterprises, narrow the gap with international standards, and achieve wider application of domestic fine blanked parts.
Priorities and Major Topics for Future Product and Technology Development
1. Research on Key Technologies for Design and Manufacturing of Progressive Fine Blanking Dies for Complex Parts
Progressive fine blanking dies for complex parts represent cutting-edge basic technology in fine blanking. Research in this field is expected to drive a significant upgrade of China’s overall fine blanking technology.
Taking progressive fine blanking dies for complex parts such as synchronizer rings, clutch plates and longitudinal composite progressive fine blanking processes and dies as breakthroughs, research will focus on key design and manufacturing technologies to rapidly upgrade domestic fine blanking die technology and narrow the gap with developed countries as soon as possible.
2. Research on Life Improvement of Fine Blanking Dies and Related Key Technologies
Die life is a comprehensive reflection of the level of die materials, processes and supporting products.
Carrying out technical research focused on fine blanking die life can not only solve the urgent problem of excessively short die life in China, but also promote technological development of die materials, fine blanking processes, supporting tooling and auxiliary products.
3. Research and Development of Combined Fine Blanking and Precision Forging Technology
Fine blanking and precision forging are two parallel manufacturing technologies.
Workpieces too thick for fine blanking require precision forging, while those too thin for precision forging must be fine-blanked; the two are closely interrelated.
The basic idea of developing a combined process is to identify integration points, such as gear parts with hubs and cam parts with short shafts.
China has a long history and high level in precision forging, which provides an effective path to提升 the overall level of domestic fine blanking technology.