In recent ten years, with importance that developing advanced manufacturing technology being fully recognized, stamping technology is highly developed in depth and breadth. Combing with high-tech, the method and the system of stamping have been changed. Permeation and integration of computer technology, information technology and modern technology of measure and control promote advanced stamping technology to be formed and developed.
The development of stamping technology is originated from auto industrial production. In the early of 1920’s, industrial production in Ford Motor greatly drove research and development of stamping technology. The research was carried out in both forming technology and formability of sheet materials. The priorities were fracture, crinkling and springback, involving estimation of formability, innovation of forming ability, analysis and control of forming processes. However, in most of 20th century, holding of stamping technology was basically indicated. Analysis tool was classical forming mechanics theory, having limitation to solution. Research focused on stamping property and forming mechanics of sheet materials, which could not meet requirements of auto industry. 1960’s was an important period for stamping technology development. Various new forming technologies came out in succession. Especially, the proposal of forming limit diagram (FLD) drove properties of sheet materials, forming theory, forming technology and quality control to develop concertedly, becoming a milestone in developing history of stamping technology.
For early development of finite element method and CAD technology in 1980’s, numerical simulation and computer application technology were highly developed and applied in stamping industry, becoming a powerful tool for research of materials deforming and design of technological processes. Auto stamping technology truly entered into analysis. Traditional sheet forming technology also began to be transferred from experience to science.
From the developing history of stamping technology in last century, we can see that:
1. Research and modification of stamping property are matched with development of stamping technology
2. The high development of auto and aircraft and energy factors are the main driving force to promote stamping technology to develop. In the new century, with environmental factors and relative legal restriction becoming prominent, design and manufacturing of light-weight auto become current priority.
3. The development of numerical simulation in forming process promotes traditional stamping technology to enter into science and advanced manufacturing technology.
4. The development of stamping technology involves materials, energy, mold and equipment. Innovation of technical methods, scientific analysis and control of process are the core of technology development. Mold technology is reflection of stamping technology development, the important factor having influence on production cycle, cost and quality of products.
The development of stamping technology
has closed relationship with materials and structure. It is predicted that environmental requirements and increasingly stringent environmental protection laws will promote auto materials and structure to change a lot in the next 10-15 years. To reduce emission of carbon dioxide in city, auto is in pursuit of light weight. The most prominent development direction is improving specific strength and specific rigidity of used materials and developing efficient light-weight structure. In structure of modern body, high strength steel accounts for about 25%. Continue developing ultrahigh-strength steel, meanwhile, combine with efficient structure and manufacturing technology, striving for reducing weight of car body by more than 20%. Increase the application of aluminum, magnesium and other low density alloy materials on auto.
The western is developing aluminum car body used in the future, which can reduce weight by 40-50%. Oil consumption of future auto is only one third of average value of current auto. The current major problems are developing low cost aluminum alloy, new structure, high efficient manufacturing methods and improving recycle technology. Once cost is figured out, aluminum alloy may become main structural materials of auto.
Since 1991, output of magnesium is increased by one time every five years, a hopeful material in the future. It is estimated that the application of magnesium will be highly raised by 2023, including large external parts of car body.
In 1980’s, the western researched stamping technology on galvanized sheet. In 1990’s, they focused on stamping on laser tailored blank and precise forming technology on various extruded tube billets. The usage of aluminum framework was also increased constantly.
Structural integration is also an important development trend. The application will be not only expanded in aircraft, but also expanded in auto in the future.