Ilyasov, A.M. and Zhamanbalin М.B. 2022. Features of the production and calibration of reference hardness test blocks: Features of the production and calibration of reference hardness test blocks. Physical Sciences and Technology. 9, 3-4 (Oct. 2022), 32–38. DOI:https://doi.org/10.26577/phst.2022.v9.i2.05.