This standard specifies a method of evaluating the microstructure of grey cast iron under optical microscope.
This standard specifies the evaluation methods for the graphite distribution and size and the quantities of pearlite, carbide, steadite and eutectic cell, and lists corresponding grading diagrams.
This standard is applicable to evaluating the microstructures of common and low-alloy grey cast irons.
2 Normative References
The following standards and documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to investigate the possibility of applying the most recent editions of these standards. For undated references, the latest edition applies to this standard.
GB/T 9439 Grey Iron Castings
GB/T 13298 Inspection Methods of Microstructure for Metals
3 Sample Preparation
3.1 Metallographic samples shall be taken, in accordance with GB/T 9439, from the test blocks or castings simultaneously poured and heat treated in the same furnace with the casting.
3.2 Metallographic samples shall be prepared according to the requirements of GB/T 13298. During cutting and preparing metallographic samples, the structure change and the peeling and tailings of graphite shall be avoided and the sample surface shall be smooth and clean and free from any gross scratch.
