Sadegh Rahmati - Imam Hussain University Mechanical Engineering Division
Mohammad Soleymani - Imam Hussain University Mechanical Engineering Division

Increasing competition in global markets is exerting intense pressure on companies to trim their product cycles continuously. Reducing the time to produce prototypes is a key to speed up the development of new products. Rapid tooling (RT) with particular regard to injection mould fabrication using rapid prototyping (RP) technology of Stereolithography (SL) may lead to savings in cost and time. Rapid prototyping techniques are proving invaluable as aids in production planning, in performance tests conducted on plastic parts and in ensuring the rapid availability of sample parts. The design to product lead-time can be significantly shortened if the production time for tooling can be shortened. Previous work at Nottingham University has shown that SL injection mould tooling can be used successfully in low to medium shot numbers. This paper looks at the failure mechanisms in SL injection mould tooling during injection. During injection, tool failure either occurs due to excessive flexural stresses, or because of excessive shear stresses. Methods of improving the tool design to reduce the chances of failure are proposed.

Rapid Manufacturing, Rapid Prototyping, Stereolithography (SL), Rapid Tooling