GB/T 3488.2-2018

This part of GB/T 3488 provides a method guide for measuring the grain size of hard alloys using metallographic detection techniques such as optical or electron microscopy.
This part is applicable to WC/Co hard alloy sintered bodies (also known as hard alloys or metal ceramics) primarily composed of WC as the hard phase, and is also suitable for measuring grain size and distribution using the line intercept method.
This part mainly includes the following four aspects:
—— Calibration of the microscope to ensure measurement accuracy;
—— Linear analysis method to obtain sufficient statistically significant data;
—— Analysis method to calculate representative averages;
—— Reporting to meet modern quality reporting requirements.
This part illustrates this recommended technique through a measurement case analysis (see Appendix A).
This part is not applicable to the following aspects:
—— Determination of size distribution;
—— Determination of shape, which still requires further research before shape determination can be achieved.
Coercive magnetic force can sometimes be used to measure grain size, but this method only involves metallographic determination. This method is suitable for hard alloys and is not applicable to powders. However, in principle, this method can also be used to determine the average size of powders that can be embedded or prepared into samples.