Search results

Polymer rapid tooling (PRT) inserts can be used as injection moulding (IM) cavities for prototyping and low volume production but lack the robustness of metal inserts. Metal inserts can withstand high injection pressure and temperature required, whereas PRT inserts may fail under similar parameters. The current method of parameter setting starts with using the highest pressure setting on the machine and then fine-tuning to optimize the process parameters. This method needs modification, as high injection pressures and temperatures can damage the PRT inserts. There is a need for a methodical process to determine the upper limits of moulding parameters that can be used without damaging the PRT inserts.

A case study analysis was performed to investigate the causes of failure in a PRT insert. From this, a candidate set-up process was developed to avoid start-up failure and possibly prolong tool life. This was then tested on a second mould, which successfully avoided start-up failure and moulded 54 parts before becoming unusable due to safety issues.

Process parameters that are critical for tool life are identified as mould temperature, injection pressure, injection speed, hold pressure and cooling time.

This paper presents a novel method for setting IM process parameters for PRT inserts. This has the potential to prevent failure at start up when using PRT inserts and possibly extend the operating life of the PRT inserts.

Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.