Research On Rapid Manufacture Of Steel Mold Through Combining Arc Spraying And Rapid Prototyping Technologies

The technique of combining arc spraying with rapid prototying to manufacture rapidly the steel mold is one recently developed advanced mold manufacturing technique. The arc spraying was performed layer by layer on the surface of the intermediate mold which was duplicated from either rapid prototying or actual part. The mold with the predetermined inner cavity size and outer appearance was eventually deposited. The manufacturing cycle and cost of the mold can get considerably reduced with this technique. Compared with the traditional mold manufacturing methods by mechanical machining, the manufacturing cyclecan be reduced by 1/2 at least and the production cost by can be decreased by 1/3 at least for the technique combining arc-spraying and rapid prototying. The technique has the extensive applying prospect in such industry fields as automotive, motocycle, household appliance and plastics.Through analyzing the microstructure and property of the mold coating obtained by arc-spraying, the materials suitable for manufacturing the mold by arc-spraying, including martensite stainless steel and high carbon steel, are selected. These materials are available for obtaining the deposition microstructure mainly composed of martensite. Thus, the cooling shrinkage of the coating can be effectively eliminated by the expansion effect of martensite transformation can offset, and the precision of the mold can be ensured.The change in the temperature and stress of both spraying partical and mold coating during cooling are investigated respectively using the simulation calculation method. The calculation results may provide the theoretical basis for predicting the deformation tendency and amount of the mold. In addition, the residual stress and residual deformation of the mold after cooling to room temperature are also calculated, and the calculated results are compared with the actually measured ones. Through these calculations, the amount of the technological experiments can be substantially reduced, and the theoretical basis for the design of the mold can be provided. The whole technological flow for manufacturing the steel mould by arc spraying is established based on the experimental results. The main technological steps include design of mold data model→design of RP prototyping→manufacture of RP prototypings→manufacture of flexible silicone intermediate mold→manufacture of rigid ceramic intermediate mold→spraying of mold→reinforcement of mold surface→grinding and assembly-→mold product. Many drawing mold and rotational mold are manufactured with the present technology, and practically used in automotive industry. The good economic efficiency has been achieved.