In the production process of metal products, metal forming technology plays a crucial role. Among them, sheet metal processing is a common metal forming method, which covers a variety of processes such as metal deep drawing and metal stamping. Metal deep drawing is the process of stretching the sheet through the deep drawing die to form the desired shape, while metal stamping is the process of using the stamping die to pressurize the sheet to achieve the molding of the product.
Mold is the automotive industry's basic process equipment, in the automotive production of more than 90% of the parts need to rely on mold forming. Manufacturing an ordinary car needs about 1500 sets of molds, stamping die accounts for about 1000 sets. In the development of new models, 90% of the workload is centered around the body profile changes. In the new model development costs, about 60% of the body and stamping process and equipment development. In the vehicle manufacturing costs of about 40% for the body stamping parts and their assembly costs.
Digital mold has become mainstream
In recent years, the rapid development of digital mold technology, is to solve the automotive mold development in the many problems faced by an effective way. The so-called digital mold technology, is computer technology or computer-aided technology (CAX) in the mold design and manufacturing process. Summarizing the successful experience of domestic and foreign automotive mold enterprises in the application of computer-aided technology, digital automotive mold technology mainly includes the following aspects:
① Design for manufacturability (DFM), i.e., consider and analyze manufacturability during design to ensure the success of the process.
② Auxiliary technology for mold profile design, development of intelligent profile design technology.
③ CAE auxiliary analysis and simulation of the process of stamping and forming, predicting and solving possible defects and forming problems.
④ Replace the traditional two-dimensional design with three-dimensional mold structure design.
⑤ The manufacturing process of mold adopts CAPP, CAM and CAT technology.
⑥ Handle and solve the problems arising in the process of mold trial and stamping production under the guidance of digital technology. Stamping and forming process simulation (CAE)
In recent years, with the rapid development of computer software and hardware, the simulation technology of stamping forming process (CAE) plays an increasingly important role. In the United States, Japan, Germany and other developed countries, CAE technology has become a necessary part of the mold design and manufacturing process, widely used in predicting molding defects, optimize the stamping process and mold structure, improve the reliability of the mold design, reduce the time of trial mold. Many domestic automobile mold enterprises have also made significant progress in the application of CAE, and obtained good results. the application of CAE technology can greatly save the cost of trial mold, shorten the development cycle of stamping die, has become an important means to ensure the quality of the mold. CAE technology is gradually making the mold design from experience design to scientific design.
Mold processing automation
Advanced processing technology and equipment is to improve productivity and ensure product quality is an important foundation. In the advanced automobile mold enterprises with dual-table CNC machine tools, automatic tool changer (ATC), automatic processing of photoelectric control system, workpiece online measurement system is not uncommon. CNC machining has been developed from purely surface processing to the surface and structure of the surface of the comprehensive processing, from low-speed processing to high-speed processing, processing automation technology is developing very rapidly.
Measurement technology into the mold automation
From CAD, CAM to a variety of processing technologies, CNC, EDM, wire cutting also includes measurement technology. We can not simply understand the measurement is to measure the accuracy. Measurement can realize the measurement automation, from the CAD model set in the accuracy requirements as well as process requirements, the system will be able to understand the place to be measured, so as to produce a real measurement program. In addition to the program, integration with the field is also included. With RFID reading, it is possible to download the program and automatically generate inspection reports.
High-strength steels for a wide range of applications
The use of high-strength steels in automobiles is increasing due to their excellent properties in terms of flexural strength ratio, strain-hardening characteristics, strain-distributing capability, and collision energy absorption. Currently, the main high-strength steels used in automotive stampings are bake-hardening steels (BH steels), dual-phase steels (DP steels), and phase-change induced plasticity steels (TRIP steels). International ultra-light body project (ULSAB) is expected to launch in 2010 in the advanced concept models (ULSAB-AVC) in 97% of the materials for high-strength steel, advanced high-strength steel plate in the car with the proportion of materials will be more than 60%, while the proportion of dual-phase steel will account for 74% of the car with the proportion of steel plate.
High-strength steel plate stamping technology is in need of a breakthrough
Now a large number of IF steel-based soft steel series will be replaced by high-strength steel plate series, high-strength low-alloy steel will be replaced by dual-phase steel and ultra-high-strength steel plate. At present, the application of domestic automotive parts of high-strength steel plate is still mostly limited to structural parts and beam parts, the tensile strength of the material used in the 500MPa below. Therefore, the rapid mastery of high-strength steel stamping technology, China's automotive mold industry is an important issue to be resolved.
Progressive die is the focus of future development
With the development of automotive stamping production efficiency and automation, progressive die in the production of automotive stamping parts will be more widely used. Complex shape of the stamping parts, especially some of the traditional process requires more than one sub-die punching sequence punching of small and medium-sized complex stamping parts, more and more use of progressive die molding. Mold master weibo content is good, worth paying attention to. Progressive die is a high-tech mold products, technical difficulties, manufacturing precision requirements, long production cycle. Multi-position progressive die will be one of the key development of China's mold products.