Basic casting theory and forming law
Due to the lack of theoretical research, the complexity and uncertainty in the filling process of investment casting are high, and the trial production is often based on experience. Therefore, the research on the formation mechanism of microstructure, stress and defect in the process of filling, solidification and post-treatment under the action of multi field coupling can provide a theoretical basis for the development of castings.
Alloy smelting and purification technology
Precision casting is the product of the close combination of high quality materials and advanced technology, so the ultra pure smelting equipment and technology is the key to its production process. For example, ion beam melting of superalloy and titanium alloy, cold wall crucible melting, electromagnetic contactless melting, vacuum melting of aluminum alloy and gas purification will be the key research directions in the future.
Special precision casting method
With the complex precision of large-scale thin-walled castings, the shape, size and inner cavity structure of castings are becoming more and more complex. The common investment casting method can not fully meet the needs of the complex components. In the future, the composite precision casting technology and special forming technology and equipment will be widely studied and applied.
Soluble (fusible) core technology
The key to realize the thin-walled hollow structure of precision casting is the research and application of various soluble (molten) core technologies. One of the key technologies of directional and single crystal hollow blade is its ceramic core technology. In addition, various soluble (molten) core formulations and preparation processes suitable for titanium alloy and aluminum alloy precision casting will be the research hotspot in the future.
Computer aided design and foundry process optimization simulation technology
The development of computer technology has brought revolutionary progress to the traditional casting industry, which has played an important role in complex integral casting modeling, process scheme design and optimization, process precise control, etc. In the future, the research on numerical simulation technology of precision casting will focus on alloy material composition design, special forming process, grain growth orientation and control, comprehensive mechanical property prediction and batch production model control, and promote the improvement of industrial information technology level in the field of basic manufacturing.
Special alloy pouring process, equipment and solidification process control technology
The microstructure, internal defects and residual stress of precision casting are all formed and evolved in the process of casting filling, so the casting and solidification process of alloy plays a decisive role in the mechanical properties, dimensional accuracy and internal quality of casting. High gradient directional solidification and structure control technology of superalloy, centrifugal filling and control technology of titanium alloy, counter gravity pouring equipment and control technology of aluminum alloy will be the hot research fields of precision casting forming and quality control in the future.
Post treatment and NDT technology of precision casting
One of the important characteristics of precision casting is that its overall mechanical properties are relatively high, which is equivalent to the level of medium-sized forgings. The post-treatment technologies such as heat treatment, hot isostatic pressing and hydrogen treatment are the key to improve the comprehensive properties of castings and eliminate casting defects. It is an important way to study the evolution mechanism and law of microstructure and defect in the post-treatment process of precision casting to realize its microstructure control and performance control. The structure of large-scale thin-walled complex cavity precision casting is complex, and the cavity, pipeline and non machining curved surface overlap, so it is difficult to carry out effective testing by common testing methods. In the future, the non-destructive testing equipment for large-scale thin-walled complex cavity structure precision casting will become the key research direction.
With the development of aviation weapon equipment, the structure and dimension of aviation investment casting are becoming more and more complex and integrated, and the technical difficulty is getting higher and higher. In order to develop complex integral precision casting components, it is necessary to effectively integrate and manage the advanced forming process and technology, take research institutes and universities as the basic theoretical research center, break through the key technical difficulties, strengthen the cooperation between factories, universities and colleges, give full play to their advantages, and strengthen the transformation of achievements. In the future, the military weapon equipment, automobile, petrochemical and other fields will adopt a large number of integral complex thin-walled precision casting structural parts, carry out research on the mechanism and law of dimensional deformation in the process of solidification forming and post sequence heat treatment, develop the corresponding precision casting molding raw materials and key heat treatment equipment, control and ensure the overall dimensional accuracy of large-scale precision casting structural parts, and meet the design requirements, It is very important to shorten the development cycle.
