Process technology molding inserts

A clear, processing-technological differentiation to the previous hot-compaction can be made and is based upon the tempering of the shaping tool, which possesses a temperature that is far below the hot-compaction temperature or that is at room temperature. The preheated, self-reinforced semifinished plate products are inserted into a cold cavity and formed under pressure. This procedure allows relatively short cycles at low molding ratios. 

For the production of mold inserts, the same possibilities and processes apply as in injection molds. The structures themselves are usually much easier to make and therefore cheaper. Other advantages are the simpler system and equipment technology and very short setup times - especially to change material, because no conversion and cleaning of machines (screw and nozzle) are required. 

The mold inserts in silicon (Figure 1.271) are produced by lithographic and etching processes, a technology that has been known for decades in the electronics industry. New in this area are the 3D methods, which make the impression of very small structures possible. In mold making, the fixing and protection of mold inserts is important. The fracture risk is very high. 

According to the current state of technology, it is only possible to encapsulate metal inserts with thermoplastic materials under series conditions without flash formation or damage in the injection molding process. Often interchangeable inserts made from copper, aluminum, or another metal are used in the mold. Here, the inserts cannot be individually adapted to the depositors, which will make regular replacement necessary. Another possibility is to compress the inserts in the injection mold. This can temporarily avoid flash formation. In this context, it must be noted, however, that damage to the injection mold and the insert surfaces will occur. 

Direct Tooling Mold inserts, which may also contain internal cooling channels, are made with 3D printing processes. The bronze infiltration leads to a higher thermal conductivity, which may be advantageous if the tendency to worse mechanical-technological properties is accepted. 

Soluble core molding The soluble core technology (SCT) is called by different names such as soluble fusible metal core technology (FMCT), fusible core, lost-core, and lost-wax techniques (3). In this process, a core [usually molded of a low melting alloy (eutectic mixture) but can also use water soluble TPs, wax formulations, etc.] is inserted into a mold such as an injection molding mold. This core can be of thin wall or solid construction. 

An additional functional station, for example for inserting and assembly processes is also gained by the cube technology The 4-sided middle plate of the mold is turning by a vertical rotary axis. 

Insert molding, or in-mold processing as it is sometimes known, is characterized by the combination of a printed or structured film with a thermoplastic substrate material. MID technology makes use of this property in a variety of process combinations. 

By comparison with the processes described in Section 7.3.5, the manufacture of LDS parts with steel tools with nonhardened inserts is the most complicated. The upside is that MID quality is comparable to that of subsequent series production. The surface quality of the moldings is such that there is no overmetahization. Even ultrahigh requirements with regard to superfine conductor widths and subsequent processes of assembly and connection technology such as chip-assembly processes are fully satisfied. 

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