The development of the foundry industry, foundry is one of the basic processes of the modern machinery manufacturing industry, so the development of the foundry industry marks a country’s production strength. According to statistics in 2008, my country has an annual output of 33.5 million tons of castings, making it the largest casting country in the world. With the continuous development of my country’s foundry industry, the domestic foundry industry will create a “Four Haves” innovative enterprise, that is, innovative ideas, innovative plans, innovative systems and systems, and innovative working methods. In terms of transformation and upgrading, it is necessary to build a new type of enterprise with six major characteristics:
- To manufacture enterprises with innovative business models whose front-end market R&D and back-end services have become larger and manufacturing links have shrunk.
- Companies that have changed from selling commodities to selling solutions and providing complete solutions.
- A digital enterprise marked by intelligence and integration. .
- Three-to-five-year speed-type enterprises.
- Enterprises with advanced technology, green manufacturing and continuous innovation.
- Create high-end products, high-quality products, guide consumption, and brand winning enterprises. With such industrial innovation, we believe that my country’s foundry industry will be more brilliant in the future, and we will wait and see for a better future.
During the “Eighth Five-Year Plan” period, the foundry machinery manufacturing was highly valued by the former Ministry of Electrical and Mechanical Services. It invested the largest special technical renovation loan and research expenses since the founding of the People’s Republic of China, and supported the development and development of products in the foundry machinery industry. “Manufacturing of large-scale shot blasting machine”, “Vertical parting boxless injection molding machine”, “Development of water glass sand used sand recycling equipment”, “Metal casting equipment” and so on have been developed and applied.
During the “Ninth Five-Year Plan” period, the foundry machinery industry undertook and completed the task of “finishing and efficient modeling and cleaning of car casting blanks and complete sets of technology and equipment”. “Development and development of efficient continuous shot blasting cleaning line for cylinder blocks” also achieved complete success. , In 1999, it completed the national high-level air-punch molding line project.
During the “Tenth Five-Year Plan” period, the average annual growth of the main economic indicators of the foundry machinery industry was more than 30%, higher than the average growth level of the machine tool industry, especially the profit growth was faster, the average annual profit growth was as high as 46%, while maintaining Higher market sales level. In addition, the complete set of resin sand molding equipment can basically meet the needs of the domestic market, changing the situation of relying mainly on imports in the past; it has been able to produce a higher-level automatic casting production line, reaching a level that can partially replace imports, and partially solve the problem of car engines. Cylinder blocks, cylinder heads and other casting blanks are also imported; high-level automatic core making machines, automatic casting cleaning machines, automatic sand processors, large-scale automatic die-casting machines, precision casting equipment and other casting machinery can basically be produced in China . It should be said that during the “Tenth Five-Year Plan” period, the product level of the foundry machinery industry has been greatly improved, laying a good foundation for the further development of China’s foundry machinery industry in the future.
During the “Eleventh Five-Year Plan” period, the equipment manufacturing industry will continue to maintain a relatively high growth rate under the stimulation of the huge international and domestic market demand. As the technical level of foundry machinery products still has a large gap with market demand, there is huge development potential and room for expansion in the development of the industry, which brings opportunities for the rapid growth of the foundry machinery industry.
During the “Twelfth Five-Year Plan” period, the foundry industry strives to become stronger internationally instead of relying solely on output. At the same time, green casting is the focus of development, and low-carbon environmental protection is the development purpose of the foundry industry. The popularity of e-commerce has also integrated the traditional foundry industry into the world of the Internet. The success of the International Foundry Network also marks the beginning of a new page in the domestic foundry industry.
At the end of the “Twelfth Five-Year Plan” period, large-scale nuclear power, thermal power, hydropower, wind power and other high-efficiency and clean power generation equipment, as well as steel, petrochemical, shipbuilding, rail transit, machine tool, aerospace, and automotive industries will provide large-scale castings, high-end key castings and various functions. Casting, the foundry industry will reach the world’s advanced level.
According to my country’s general goal of common prosperity, and ultimately to narrow the gap between the East and the West, my country will implement the strategy of the east to drive the development of the west. This strategy is also applicable to my country’s foundry industry. The foundry industry in the eastern part of my country, because of its own location advantages and the support of national policies, has a good development trend, and its development level is much higher than that of the foundry industry in the western region.
In order to implement my country’s western development strategy and promote the economic development of the western region, we must promote the development of basic industries such as foundry in the western region to lay a solid foundation for the economic development of the western region. This requires the foundry industry in the eastern part of my country to drive the development of the foundry industry in the west with its relatively advanced technological advantages, relatively strong capital advantages, and management advantages, so as to achieve the overall goal of common prosperity.
To solve the problem of vicious competition in the foundry industry, we must first solve the survival problem of these foundries. Promoting the upgrading of my country’s foundry industry requires the development of high-end casting. The development of high-end casting can change the structure of my country’s foundry industry, reduce the number of low-end foundries, reduce the pressure of competition in the low-end casting product market, and make the low-end foundry market Gradually return to an orderly state and solve the problem of vicious competition in one fell swoop.
The specialized production of my country’s foundry industry has begun to take shape. Nowadays, a number of specialized foundry production enterprises with distinctive characteristics have been formed. These companies mainly include: high compaction molding + advanced core making + double smelting engine castings casting enterprises; large-scale mechanized production of automobile castings such as brake hubs, brake discs, exhaust pipes, etc.; resin self-hardening sand as the main body Large-scale casting production plants for machine tools, cabinets, wind power, etc.; foundries and lost foam foundries with the V method process as the main body; crankshafts and grinding balls production plants with metal or metal sand coatings; silica sol or ethyl silicate High-end investment precision casting plant with grease as the binder; ordinary steel precision casting plant with water glass as the binder; centrifugal ductile iron casting plant and centrifugal gray iron casting plant; non-ferrous alloy sand casting (high/low /Poor) Foundry and so on.
From the long history of casting technology to today’s modern casting technology or liquid solidification forming technology, this is not only related to the in-depth and development of the crystallization and solidification theory of metals and alloys, the continuous emergence and improvement of various solidification technologies, and the application of computer technology. And so on, but also closely related to the development of chemical industry, machinery manufacturing, manufacturing methods and technology. 
The development of solidification theory Crystallization and solidification are the core of the casting formation process. It determines the formation of the structure and defects of the casting, as well as the performance and quality of the casting. In the past 30 years, with the help of physical chemistry, metal science, non-equilibrium thermodynamics and kinetics, advanced mathematics and computational mathematics, researches on heat transfer, mass transfer, and solid-liquid interface have made the theory of metal solidification great. The development of this has not only made people have an in-depth understanding of the solidification process and organizational characteristics under many conditions, but also promoted the proposal, development and production application of many solidification technologies and liquid solidification forming methods. For example, the solidification theory has established some functional relationships between the cooling rate of castings, the grain size, and the grain size and the mechanical properties of the castings, which provides a basis for controlling the casting process parameters and the mechanical properties of the castings.
The development of solidification technology Controlling the solidification process is an important way to develop new materials and improve the quality of castings. Sequential solidification technology, rapid solidification technology, acquisition of composite materials, semi-solid metal casting and forming technology, etc. are concentrated representatives.
- Sequential solidification technology The so-called sequential solidification technology is to discharge the heat of the liquid metal in a certain direction, or to perform rapid solidification of the liquid metal in a certain direction, so that the growth (solidification) of the crystal grains proceeds in a certain direction, and finally A process method to obtain castings with unidirectional grain structure or single crystal structure. Due to the continuous advancement of cooling and control technology, the intensity and directionality of heat discharge are continuously improved, thereby increasing the temperature gradient in the liquid phase at the front of the solid-liquid interface, which not only improves the directionality of grain growth, but also makes the structure finer. Long, straight, and extend the orientation zone. Sequential solidification technology has been widely used in the production of cast superalloy gas turbine blades. Due to the excellent mechanical properties of the structure grown along the orientation, the operating temperature of the blades is greatly increased, thereby enabling aeroengines Improved performance. The latest development of sequential solidification technology is the production of single crystal castings, such as single crystal turbine blades, which have higher working temperature, thermal fatigue strength, creep strength and corrosion resistance than general sequential solidification columnar crystal blades. The aeroengine using this kind of superalloy single crystal blade effectively increases the thrust and efficiency of the aeroengine, and greatly improves its performance.
- The rapid solidification technology is a process that transforms the liquid alloy into a solid state under a cooling condition (103-109 K/S) much faster than the cooling rate under the conventional process conditions (10-4-10K/S). It enables the alloy material to have excellent structure and properties, such as very fine grains (usually <0.1-0.01 um> or even nano-scale grains), segregation defects of alloy elements and ultrafine precipitates with high dispersion, and high material Strength, high toughness, etc. The rapid solidification technology allows the liquid metal to break away from the conventional crystallization process (nucleation and growth) and directly form a solid material with an amorphous structure, the so-called metallic glass. This type of amorphous alloy has a long-range disordered structure with special electrical, magnetic, electrochemical and mechanical properties, and has been widely used. For example, it is used as the core material of the control transformer, the material of the parts in the computer magnetic head and peripheral equipment, and the fiber welding material. Rapid solidification is receiving increasing attention from many parties.
- Another development of composite material preparation and solidification technology is used in the preparation of composite materials. The so-called composite material is to introduce a reinforcing phase or special composition in a non-metal or metal matrix, and control the solidification to make the reinforcing phase in the desired way A distributed or arranged material with special properties. Because the matrix of the composite material has high fracture properties, coupled with the existence of the reinforcing phase, it can show different properties from ordinary single-phase structured materials, such as high strength, good high temperature performance and fatigue resistance, and many have been developed. A kind of technological methods for preparing composite materials, such as combining sequential solidification technology to prepare self-generating composite materials. The application prospects in this field will become wider and wider.
- Semi-solid casting The semi-solid metal casting forming technology has entered the industrial application stage after more than 20 years of research and development. The principle is to carry out strong stirring during the solidification process of liquid metal (mechanical, electromagnetic or other methods can be used), so that the dendritic network skeleton that is easily formed by ordinary casting is broken to form a dispersed granular structure. Semi-solid molten metal, which has a certain degree of fluidity, can then be formed by conventional forming techniques such as die casting, extrusion, and die forging to produce blanks or castings. Semi-solid metal casting molding overcomes the shortcomings of shrinkage cavity, shrinkage porosity, pores and dimensional deviation that are easy to produce in traditional casting molding. It has low forming temperature, prolongs mold life, saves energy, improves production conditions and environment, and improves casting quality (reduce pores) And solidification shrinkage), reducing machining allowance and many other advantages. The semi-solid metal forming process will become one of the most promising near-net shape forming technologies in the 21st century.