Development trend of foundry technology in China

★ 4.1 cast alloy materials

Aiming at strengthening and toughening, lightening, precision and high efficiency, new cast iron materials are developed; ADI heat treatment equipment is mainly developed, national standards are formulated as soon as possible, and new technologies of ADI are popularized (such as interrupted heat falling sand method, interrupted normalizing method, etc.); manufacturing technology of thin-wall high-strength gray iron castings and cast iron composite materials (such as in-situ reinforcement) are developed Preparation technology of granular iron-based composite materials, etc.), surface or local strengthening technology of iron castings (such as surface laser strengthening technology, etc.). Develop new wear-resistant, corrosion-resistant and heat-resistant special alloy materials; develop new varieties of cast alloy steel (such as cast steel materials with high performance price ratio such as nitrogen-containing stainless steel), improve material performance, utilization rate, reduce cost and shorten production cycle. Develop high quality aluminum alloy materials, especially aluminum matrix composite materials. The action principle of alloying elements in aluminum alloy and the strengthening way of aluminum alloy are studied. The methods of reducing the content of Fe, Si and Zn in the alloy, improving the strength and toughness of the alloy and the way of heat treatment and strengthening of the alloy are studied.

★ 4.2 casting raw and auxiliary materials

Establish a new raw and auxiliary material system suitable for high-density clay molding sand, according to the characteristics of different alloys, castings, production environment, develop different kinds of raw sand, less pollution-free high-quality shell core sand, pay close attention to the research and development of China’s raw sand resources, carry out the research and development of replacement of special sand and artificial casting sand; focus on the development of new-type coal powder and replacement of green sand binder On the development of coal powder additives.

Promote the application of computer expert system in the quality management of molding materials such as molding sand.

★ 4.3 alloy smelting

Development of 5t/h cupola and the use of external hot air supply, water-cooled and non lining continuous cupola as required, cupola induction furnace duplex melting process, and advanced iron melt desulphurization and filtration technology (development of new low cost foam ceramic filters with low sintering temperature and short sintering time), new type of alloys suitable for all kinds of active alloys and high temperature physical and chemical properties Foam ceramic filters, special-shaped foam ceramic filters suitable for special casting processes such as investment casting, metal mold casting, in-depth study of the filtration and purification mechanism of foam ceramic filters and the mechanism of the solidification process of metal foam, and systematically study the application technology of foam ceramic filters, including the choice of aperture and thickness, the placement method, the gating system design and pouring temperature. And speed and metal hydraulic head control, etc., carry out the series and standardization of foam ceramic filters, equipped with direct reading spectrometer, carbon equivalent fast detector, quantitative metallographic analyzer and spheroidizing rate detector, and apply microcomputer technology to thermal analysis of cast iron melt.

★ 4.4 sand casting

To improve the internal and external quality of castings, such as dimensional accuracy and surface finish, reduce machining allowance, and further promote the application of high mechanization, automation and high-density wet sand molding technology, such as air impact, high pressure, injection molding and extrusion molding, is the main development direction of small and medium-sized castings production in the future. It is the key to improve the quality of bentonite by using nano technology to modify bentonite or adding binder in bentonite.

★ 4.5 special casting

Develop new technology of investment casting mould and die material, use silica sol or ethyl silicate as binder; adopt precision, large-scale and thin-wall investment casting forming technology; adopt rapid forming technology to replace traditional wax mold forming technology, simplify process and shorten production cycle; develop wax pressing equipment, shell making manipulator and oil fired shell baking furnace suitable for China; develop high-quality shell binder To increase the type of castable alloy and expand the application of technology.

★ 4.6 quality assurance

Improve and perfect the existing mature and practical casting instruments and equipment, strive to achieve multi-functional, integrated, automatic and intelligent, and conduct decentralized online measurement and control for each link of casting production. The computer and CAD expert system module are used to connect the automatic measurement and control instruments and equipment of relevant links, and the actuator is used to realize the closed-loop automatic control of each link. The intelligent measurement and control system of each link is connected with the computer system of the factory management center to form the intelligent closed-loop automatic control system of the factory to realize the production quality prediction and control. The factory automatic control system is connected with industry information network and expert system through high-speed information channel to realize remote consultation and control.

★ 4.7 informatization

Develop a computer expert system which is distributed, integrated and diversified, and suitable for all aspects of foundry production (such as design, manufacturing, diagnosis, supervision, planning, prediction, interpretation and teaching). And in the production and use of continuous improvement, to multi-functional, efficient, practical goal development, so that it is integrated with CAD / CAPP / CAE / CAM; promote the forefront of online expert system control research.