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Micrograph 595 and full record
- Micrograph no
- 595
- Brief description
- Thermoset case of an electrical plug
- Keywords
- electrical, formaldehyde, injection moulding
, network, plug, polymer , thermoset, urea, urea formaldehyde - Categories
- Polymer
- System
- Urea formaldehyde
- Composition
- Not specified
- Standard codes
- Reaction
- Processing
- Reaction injection moulding
- Applications
- Thermosets are cross-linked networks; hard but unprocessable after the initial reaction. They are used as adhesives, composite matrices, and to make casings for electrical equipment.
- Sample preparation
- A cross-section has been cold-mounted and stained with dye to highlight the filler material
- Technique
- Reflected light microscopy
- Length bar
- 100 μm
- Further information
- The microstructure revealed by the dye consists of seams of filler material (flour or wood-pulp) which is introduced to the melt in a 2:1 ratio part way through the moulding process. Urea thermosets are used because they are hard, inexpensive, and have good resistance to electrical arcing. An additional benefit of a thermoset as opposed to a thermoplastic in this application is that should a failure occur, it will fail in a safe mode (charring, but retaining it form, rather than melting).
- Contributor
- J A Curran
- Organisation
- Department of Materials Science and Metallurgy, University of Cambridge
- Date
- 03/10/02
- Licence for re-use
Attribution-NonCommercial-ShareAlike 4.0 International
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