Strategy of traditional manufacturing industry was that scale benefit was the first. Price and quality first was put forward in 1980’s, developed into market response first in 1990’s. Reducing development cycle of products and invest risks on developing new products have already become the key for enterprises surviving.
In recent years, strategic emphasis on manufacturing market has already transferred from cost and quality to time and response. Pushing diversified products into the market as soon as possible is the priority for manufacturers holding opportunities on market and surviving. Rapid prototyping has already become hot spots of international research, providing an advanced method for enterprises improving their own competitiveness.
The technology is a newly-developed manufacturing technology based on materials incremental forming, considered as a revolutionary breakthrough of manufacturing in 20th century, which can manufacture injection mold, die-casting mold, stamping mold and other complicated precise mold. At present, the technology has already been used in auto, aviation, shipping, household appliances, industrial design, medical treatment, construction, crafts manufacturing and toys. With the technology developing and improving continuously, the application is also expanded constantly.
In auto and household appliances manufacturing, parts formed by mold account for 50%~70% of manufacturing time. Mold manufacturing is bottleneck limiting auto, household appliances and light industry to develop in China. With hard or soft ware and materials of rapid prototyping developing and improving continuously, the strength and precision of rapid prototype are improved constantly. Rapid prototyping has gradually gone deep into rapid mold manufacturing.
Although rapid prototyping does not come out for a long time, the huge benefit brought to manufacturing causes the technology widely applied, particularly promoting the design and manufacturing of mold to highly develop. Rapid prototyping can precisely manufacture core and cavity of mold, and it also can be directly used for manufacturing plastic samples during injection molding
to discover and rectify the error. For the application of rapid prototyping, the design and manufacturing of mold gradually tend to digitization and rapidity so that mold manufacturing makes a great process on reducing period and cost.
Rapid prototyping mainly depends on solid model, using copy (metal spraying, electroplating, pouring of composite and precision casting) to rapidly manufacture the main parts of mold (punch pin, die, cavity and die). Generally, manufacturing cycle is only 1/5~1/10 of traditional numerical control cutting and cost is only 1/3~1/5 of traditional cost. Diverse technologies have already been developed based on materials of mold, manufacturing cost, materials of rapid prototype model, materials of rapid prototype model, batch quantities and precision of mold.
Currently rapid prototyping can be classified into indirect rapid tooling and direct molding. The methods based on mold manufactured through RP rapid manufacturing are mainly indirect rapid tooling. Based on different materials, molds manufactured by indirect rapid tooling are classified into soft tooling, bridge tooling and hard tooling. Soft tooling often refers to the silicone rubber mold. The model is manufactured by using SLA, FDM, LOM or SLS, then, manufactured into silicone rubber mold further. The mold is poured two compositions of polyurethane (PU), solidified and forming parts. Bridge tooling generally refers to the epoxy resin mold directly used for injection molding. The cost of epoxy resin mold is only fractions of traditional injection mold and production cycle is significantly decreased. The service life of the mold is less than steel mold while it is higher than silicone mold, which can meet the demands of medium or small scale production. Hard tooling refers to steel mold, the metal mold manufactured by using indirect rapid tooling and rapid prototyping.