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Polymer Composites
- Thread starter Comp448
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Manufacturers' data sheets will cover many of the basics. Hexcel, Cytec, Gurit, Park Electrochemical (all .com apart from parkelectro.com) and many, many others. Also recommended: ASM Handbook Vol 21 Introduction to Composites and MIL-HDBK-17 (now CMH-17 and money needed); see and enter MIL-HDBK-17 in the Document ID box.
The cure schedules in data sheets often cover subtleties such as when to put in a dwell or allowances for laydown methods such as automated fibre placement (for instance so-called semi-preg, where the plies aren't completely prepregged, leaving a gap in the middle to aid extraction of air, is often not recommended for AFP).
Lower performance resins often have more flexibility in the cure shedule (such as three days at room temp vs. x hours at 90°C and vacuum vs. some autoclave pressure), whereas higher performance ones may have fewer options of this sort. Sometimes different cures may have different degrees of cure listed, or sometimes anticipated levels of porosity. Perhaps oddly there also seems to be less detailed information on lower performance resins such as polyesters compared with, say, aerospace epoxies.
Having a good relationship with your supplier's team is hard to over-recommend (much helped if you buy a lot of material...).
In general: more pressure means less porosity and a higher quality laminate; more temperature (often can't be varied for a given resin) means a higher Tg or heat deformation temperature. However, the data sheets have details of all that sort of thing.
More detail about the types of naterial will no doubt get you more useful responses. E.g., thermoplastics as opposed to thermosets, injection as opposed to prepregs, etc.
The cure schedules in data sheets often cover subtleties such as when to put in a dwell or allowances for laydown methods such as automated fibre placement (for instance so-called semi-preg, where the plies aren't completely prepregged, leaving a gap in the middle to aid extraction of air, is often not recommended for AFP).
Lower performance resins often have more flexibility in the cure shedule (such as three days at room temp vs. x hours at 90°C and vacuum vs. some autoclave pressure), whereas higher performance ones may have fewer options of this sort. Sometimes different cures may have different degrees of cure listed, or sometimes anticipated levels of porosity. Perhaps oddly there also seems to be less detailed information on lower performance resins such as polyesters compared with, say, aerospace epoxies.
Having a good relationship with your supplier's team is hard to over-recommend (much helped if you buy a lot of material...).
In general: more pressure means less porosity and a higher quality laminate; more temperature (often can't be varied for a given resin) means a higher Tg or heat deformation temperature. However, the data sheets have details of all that sort of thing.
More detail about the types of naterial will no doubt get you more useful responses. E.g., thermoplastics as opposed to thermosets, injection as opposed to prepregs, etc.
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