Composition and Requirements of Solder Paste Flux
1. The basic composition of flux in solder paste.
The basic composition of flux in solder paste is shown in Table 1.
Table 1 Basic composition of solder paste flux.
Necessary tackiness for fixing
Cleans the metal surface
Amine, Amine hydrochloride, etc
Preventing the separation of solder powder and flux and adjusting the
Hydrogenate castor oil, carnauba wax, etc
Adjusting solder paste viscosity
Ethylene glycol, Glycol; Diethylene glycol,
2. Basic requirements for solder paste flux.
The solder paste flux is the carrier of the solder powder. A good solder paste flux should meet the following conditions.
First, the solder paste flux should have a high boiling point to prevent the paste solder from splashing during reflow;
Secondly, the solder paste flux must have sufficient viscosity to prevent the solder alloy from settling during storage;
Third, the halogen content of the solder paste flux should be as low as possible to prevent corrosion of components after reflow soldering;
Fourth, the solder paste flux should have low hygroscopicity, preventing the solder alloy from absorbing water vapor in the air and oxidation.
The expansion ability of the solder paste flux during the reflow process is related to the rosin mixture, thickener, and activator. Rheology, slump, viscosity curve, reflow temperature curve, etc. can generally be used to describe the quality of the prepared solder paste.
*Disclaimer: Except for "reprinted" articles, the copyright of the original content published on this site belongs to Shenzhen Fitech. Without consent and authorization, it may not be reproduced, reproduced, quoted, changed, or published. This article is originally created by the author, and the content of the article is the author's personal opinion. "Reprint" is only to convey a different point of view and does not mean approval or support for the point of view. If there is any infringement, please contact us, and we will delete it!