Abstract: The disclosure describes a method of making flaked metal powders having a narrow particle size distribution, a whiter color and a very high sparkle effect. A heterogeneous liquid system comprising an inert liquid and a lubricant and including a finely divided metal is subjected to attrition in an enclosure in which there are a plurality of attritive elements. An agitator is moved through the elements to displace those in its path. In this method, the weight ratio of attritive elements to finely divided metal is between 70:1 and 90:1, the weight ratio of finely divided metal to lubricant is between 100:1 to 20:1 and the weight ratio of inert liquid to finely divided metal is between 0.5:1 to 2.5:1. Flaked Al, Cu, brass, stainless steel, nickel, cupro nickel powders and the like are obtained by this method.

Abstract: Flaked metal powders are made by subjecting finely divided metal and a lubricant in a heterogeneous liquid system in a ball mill in which there is a mass of attritive elements through which an agitator is moved to displace the elements. The weight ratio of attritive elements to finely divided metal is within the range from 37 to 1 to 10 to 1. The weight ratio of inert liquid to finely divided metal is preferably within the range from 0.5 to 1 to 1 to 4. The weight ratio of finely divided metal to lubricant is preferably within the range from 30 to 1 to 1 to 1. The attritive elements preferably have a diameter within the range from 1/32 inch to 1 inch (0.8 to 25.4 mm). Preferred temperatures, times and other conditions are disclosed. Apparatus for carrying out the method includes, in addition to the attritive elements and the agitator, additional agitating means producing agitation in a relative direction counter to that of the agitator. The additional means may be rods extending among the attritive elements.