you are not logged in, login. new entry
text: sort by
tags: modified
type: chronology
hide / edit[0] / print
ref: -0 tags: tungsten eletropolishing hydroxide cleaning bath tartarate date: 03-28-2017 16:34 gmt revision:0 [head]

Method of electropolishing tungsten wire US 3287238 A

  • The bath is formed of 15% by weight sodium hydroxide, 30% by weight sodium potassium tartrate, and 55% by weight distilled water, with the bath temperature being between 70 and 100 F.
    • If the concentration of either the hydroxide or the tartrate is below the indicated minimum, the wire is electrocleaned rather than electropolished, and a matte finish is obtained rather than a specular surface.
    • If the concentration of either the hydroxide or the tartrate is greater than the indicated maximum, the electropolishing process is quite slow.
  • The voltage which is applied between the two electrodes 18 and 20 is from 16 to 18.5 volts, the current through the bath is 20 to 24 amperes, and the current density is 3,000 to 4,000 amperes per square foot of surface of wire in the bath.

hide / edit[0] / print
ref: -0 tags: polyimide epoxy potassium hydroxide etch adhesion date: 06-25-2015 00:28 gmt revision:0 [head]

Improvement in the adhesion of polyimide/epoxy joints using various curing agents

  • Used 1M KOH, ~2min, followed by 0.2M HCl for 6 min to ring-open the imide.
  • PMDA/ODA polyimide (Pyromellitic Dianhydride, single aromatic ring + 4,4 diamino diphenyl ether )
  • Epoxy of the DGEBA + linear amide or aromatic (3,3 methylenedianiline)
  • Best result was with a polyamide curing agent, and high-temp curing profile. Unlikely that this will work for us, parylene will decompose..