XRD study of variation of strengthening effects in carbonitrided 20Cr3MoVW steel by heat treatment

Abstract

This paper discloses the findings of an XRD investigation of microstructural characteristics and calculations of their contribution to hardening of carbonitrided 20Cr3MoVW steel subjected to three heat treatment conditions. A method for evaluation of the total yield strength using X-ray diffraction data is proposed herein. It is based on a model of the steel strengthening being linearly affected by several microstructure strengthening mechanisms. Analysis of changes in depth profiles of the estimated yield strength with heat treatment is given together with comparison against microhardness distribution in the hardened case.

Keywords:

• Carbonitriding
• Heat treatment
• X-ray diffraction
• Hardening
• Yield strength
• Microstructure
• Hardness

Acknowledgement

Author expresses his immense gratitude to Tamara V. Pisarenko, head of the metallurgical lab at JSC ‘Krasny Octiabr’, for providing test specimens, helping with specimen treatment and getting access to mechanical test data and test pieces.