ISO 2624 Copper and Copper Alloys - Estimation of Average Grain Size

EUROLAB laboratory provides testing and compliance services within the scope of ISO 2624 standard. This standard specifies three procedures and expression rules for estimating the average grain size of copper and copper alloys consisting mainly of single phase. The comparison procedure (comparing the sample with a standard chart) is the most convenient and accurate enough for most commercial purposes. In case of disagreement, it is recommended to use the Heyn or Jeffries procedures with a higher degree of accuracy (cutting procedure and planimetric procedure, respectively).

Grain size estimates will be made in three or more representative areas of each sample section. In known coaxial structures, it is sufficient to take only a representative section from the sample. For non-coaxial or unknown structures, three sections should be prepared, each at right angles to the other. The sample must be carefully prepared to reveal grain boundaries using a contrast etching to conform to standard charts.

Estimation of grain size is made by direct comparison of the projected image of the photomicrograph of a representative area of ​​the test sample with either photomicrographs of the standard grain size series or their appropriate reproductions; When a projection microscope is not available, a bench microscope can be used. To facilitate comparison, it is recommended that mechanical arrangements be made to allow standard photomicrographs to be juxtaposed with the successively projected image.

Grain size is estimated by the number of counts on the ground glass screen of a projection microscope, in the image in a bench microscope equipped with a graticule, in photomicrography of a representative area of ​​the sample, or in the sample itself. Includes grains intersected by one or more straight lines long enough to provide at least 10 intersections per line for normal purposes and at least 50 intersections for all lines and at least 200 intersections for referee purposes.

EUROLAB assists manufacturers with ISO 2624 test compliance. Our test experts, with their professional working mission and principles, provide you, our manufacturers and suppliers, the best service and controlled testing process in our laboratories. Thanks to these services, businesses receive more effective, high-performance and quality testing services and provide safe, fast and uninterrupted service to their customers.