SEDL / STP / STP189-EB / STP44112S

Non-Corrosive Fluxes—Evaluation of Spread and Corrosion Properties

Sohl, H. C.
Research Investigator, Federated Metals Division, Am. Smelting and Refining Co., South Plainfield, N. J.

Pages: 8    Published: Jan 1957

Download this paper for $25 PDF (140K)          View License Agreement
Abstract

Solder fluxes were at one time divided into two classifications: noncorrosive and corrosive. The noncorrosive fluxes generally were composed of different types of natural rosins, while the corrosive fluxes contained zinc chloride (ZnCl²), ammonium chloride (NH⁴Cl), and hydrochloric acid (HCl), either separately or in various combinations. This situation existed until the period between 1940 and 1950 when there developed a need for an essentially noncorrosive flux with better solder flowing characteristics than those obtainable with plain rosin.