Study On The Dimension Precision Based On Rapid Prototyping

In the more competitive market at the present, the enterprises have to quickly response to the customer's requirements for the commodity. Mould is the key of process equipment. Reducing the development period and the manufacturing cost, mould is reasonable measures to improve its competitiveness. The rapid tooling based on the rapid prototyping technology has the advantage of short manufacturing period, low cost and satisfied precision and life, which has the prominent economic benefits. In this paper, based on the combination of rapid tooling and ceramic precision casting technology, the ceramic rapid tooling technology with rapid prototyping is analyzed, which provides a new method for metallic mould manufacturing.The rapid tooling technology based on rapid prototyping now is at the developing stage. Some existed problems are the surface and dimension precision of prototyping based on the theory of discrete cumulating, the poor general mechanical property for high precision and high surface quality of durable mould, the ambiguous dimension transferring law among each process. The above problems are the main obstacles for rapid tooling development and application. The study and countermeasure for the rapid tooling precision is done in this paper.The combination process of rapid tooling and precision casting technology is studied, and each process arrangement is compared, at last the rapid tooling method adopting ceramic precision casting technology is analyzed, and the influencing factor on dimension deviation during the ceramic precision casing process is found.Mould of ceramic model based on rapid prototyping manufacturing belongs to the category of precise casting. The temperature changes rapidly with the space and time of metal solidification, the same thing happens to hot physics performances and phase transition, which belongs to the typical non-linear rapid transient heat conduction. The temperature field and stress-strain field when metal solidification are two-way coupling, the influence of stress-strain field towards temperature field is very small, which can be ignored. According to this theory, reasonably simplify the finite element analysis solving model, and establish a finite element analysis precise close ring controlling system.The hot-structure coupling module is adopted when analogously calculate, byindirect solving method a simulation analysis on temperature field and size change simulation is established, through simulating of models of different length and width the shrinkage amount and shrinkage percentage of different basic size casting can be found, which can offer the theoretical foundation and guide for temperature and size change in complicated solidifying course and offer the reliable compensation basis for size controlling of rapid tolling, the casting which can meet size precision demand can be got finally.