Silicone to Metal Bonding Soft and Hard

It is also possible to bond silicone rubbers to various substrates which are not injection moulded. Such materials range from steel and aluminium to ceramics, glass or any other solid. 

In such cases the processor basically has the choice between undercuts, primers or primerless self-adhesive silicone rubber. 

The major difference is that the hard component cannot be produced in the same machine, it is inserted into the mould in which it is finally overmoulded with the silicone rubber part. Metals, ceramics, glass, etc., are not too sensitive to high temperatures, which allows the process to run at a higher productivity than in the previous case, see Section 11.3.2, where cycle times are longer due to lower moulding temperatures for the silicone part. 

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