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Quality control
- Thread starter geobert
- Start date
geobert
Check with the maker of the material. while some put an expiration date on both the resin and the hardener, most often the resin will have a shelf life that is longer than the hardener. You may be able to extend the life of the product by replacing the hardener.
From a practical point of view, running materials past their expiration dates is not worth the risk of having a batch not cure properly when you need it most.
Buy what you need when you need it, and try to avoid the expense of having large quantities of material laying around, picking up recertification tickets until you have to throw it away anyway.
With Pre-preg materials you can cut off a test coupon, lay it up and cure it and see if it meets the original spec. You also have to be wary of the number of out times for that material when you do that.
This may not quite be the answer you were looking for but it should help.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
Check with the maker of the material. while some put an expiration date on both the resin and the hardener, most often the resin will have a shelf life that is longer than the hardener. You may be able to extend the life of the product by replacing the hardener.
From a practical point of view, running materials past their expiration dates is not worth the risk of having a batch not cure properly when you need it most.
Buy what you need when you need it, and try to avoid the expense of having large quantities of material laying around, picking up recertification tickets until you have to throw it away anyway.
With Pre-preg materials you can cut off a test coupon, lay it up and cure it and see if it meets the original spec. You also have to be wary of the number of out times for that material when you do that.
This may not quite be the answer you were looking for but it should help.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
- Thread starter
- #3
berkshire,
Thanks for your feedback.
Regarding prepreg I am thinking to cure the material and carry out a mechanical test (strength & elongation tensile) and se if it meets the specification on the technical datasheet.
When prepreg is at B-stage(partially cured), can I use the differential scanning calorimetry(DSC): glass transition and anthalpie to extend the expiration date?
I heard that the gel and flow can be used to extend the shelf life of prepreg. Is it true?
How to interprete the results?
Thanks in advance.
Geobert
Thanks for your feedback.
Regarding prepreg I am thinking to cure the material and carry out a mechanical test (strength & elongation tensile) and se if it meets the specification on the technical datasheet.
When prepreg is at B-stage(partially cured), can I use the differential scanning calorimetry(DSC): glass transition and anthalpie to extend the expiration date?
I heard that the gel and flow can be used to extend the shelf life of prepreg. Is it true?
How to interprete the results?
Thanks in advance.
Geobert
I would just suggest using gell and flow, if you have a gell time meter, and using cured barcol hardness of sample.
Again watch the out times, you can reduce the shelf life simply by pulling it out and thawing it to get your sample.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
Again watch the out times, you can reduce the shelf life simply by pulling it out and thawing it to get your sample.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
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