I knew a guy from Ecole Plytechnique du Montreal who showed me a “self healing material”. There are micro spherical resin bubbles imbedded and also solid catalyst crystals uniformly distributed inside. When crack develop the bubbles hit by the crack will bleed and liquid resin in contact with...
We are curing phenolic/aramid prepreg parts in oven under vacuum and autoclave under 15, 30 and 45 psi pressure since 2003 and glass phenolic since 2006. No important problems occurred. Few bags puncture from time to time due to bridging or vacuum ports sliding during manipulation. Reusable...
I have to tell you that I received four plates phosphoric anodized, I bonded them in the same conditions, same material, all samples had high peel results, |I was able to reach 89 pound per linear inch . . . it may be sulphuric anodized surface not appropriate to bonding, I just had luck with...
I'm measuring primer thickness using elcometer 345 probe. On flat, bare metal panels primer tickness is between 0.15 mils and 0.17mils, that is actual paint gun setup. On anodized panels I can't measure the thickness because of anodized layer, even to make “0” is impossible, the error is around...
What I see is that each strip that fails - has between .040-.090” cohesive failure at the very beginning and than changes to adhesive failure within next .020”. I just checked bonding thickness, it seems to be .003-.005” almost uniform on each sample. Carrier I used mat and knit (knit tested in...
Cohesive failure, adhesive on both surfaces in high results.
On the others samples it looks like primer doesn't stick on the anodized surface, the strip is clean, primer traces on it, most of the primer and all adhesive is on the outer strip . . . like release agent was used instead of anodize...
I'm trying to bond two 17”x17” aluminum plates with 3M AF163-2 structural adhesive. The plates are modified sulfuric acid anodized, primed with 3M EC 3960 adhesive primer within 4 hrs. after anodization , adhesive film applied and cured 250F/ 45psi 90min.
Lap shear test per ASTM D1002 gives...
We have a receiving procedure (maybe not the best) for tack test preinpregnated cloth:
- clean a steel plate using a solvent (M.E.K.) and dry it.
-cut the specimens of prepreg 2" by 2", apply the specimen to the plate using light hand pressure, remove the backing film, apply a second specimen on...
A carbon – epoxy mold .200” thick was donated by an aeronautical composite manufacturer (we don't know exactly what resin and tissue was used to manufacture the mold). This mold has a .250” hole machined throw. We intend to laminate few parts (8-10) from fiberglass epoxy 350F autoclave cure...
Thanks for your answer, . . . indeed I was waiting a reply from compositgeek or compositepro.
As far as I know any solvent isn't a proper diluent for epoxy, but since an important industrial use for acetone involves its reaction with phenol for the manufacture of bisphenol A, I hope that may...
I know some of you have a strong background in chemistry.
In our reparation process we are using Epocast 50A two component epoxy resin ( http://korsil.ru/pdf/50A1-946(US).pdf ). The resin has very good laminating properties but is too viscous to inject it with a syringe needle.
May I add a few...
During my last stage I was surprised to notice that bagging sequence learned at school (prepreg layup – oven/autoclave cure) is not exactly the same that is used in all aeronautic shops. More, now I saw a few of the same parts bagged without bleeder. Does it means that bleeder use is optional...
