PSI - Issue 40

N.A. Makhutov et al. / Procedia Structural Integrity 40 (2022) 264–274 Nikolay A.Makhutov at al. / Structural Integrity Procedia 00 (2022) 000 – 000

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1998; Makhutov, 2008; Dawn Carmichael D., 2019). The rocket engines considered in this paper belong to the category of critically and strategically important objects of the manmade environment. The analysis of their strength, service life, and integrity is based on the combined application of traditional and new experimental, analytical and numerical methods of calculation, testing, and diagnostics of the state and integrity of their load-bearing components at all stages of their life cycle (Frolov, 1998; Makhutov, 2008; Makhutov, 2017; Rouhollah Pour, H., 2018). These technologies include: - design technologies that are based on analytical and numerical solutions of boundary value problems related to the assessment of stress-strain states and criterion assessments of strength and service life; - manufacturing technologies for the main and auxiliary components of critical technical systems with the development of mathematical and physical models of structural materials, as well as mechanical, thermal, laser, electronic, powder, superfine, and nano-processing procedures; - technologies for laboratory, bench, and field tests of critical components and prototypes of analyzed units using experimental multiparameter technical diagnostics of operating procedures and the condition of load-bearing components; - operation control technologies that take into account hazardous normal and emergency situations with the use of new methods and systems for technical diagnostics of accumulated damages, reaching limiting states and emergency protection.

Nomenclature a H

hydrogen diffusion into the metal and its concentration

accumulated damage modulus of elasticity amplitudes of strains

d E e a e C e n е y

fracture strain maximun strain nominal strain

e max

yield strain of the material

e

strain rate;

0 e K t M b M t

strain rate during standard tests theoretical stress concentration factor

bending moment torsion moment

strain hardening exponent numbers of loading cycles numbers of revolutions safety factors for strains number of launches safety factor for stresses transverse forces centrifugal forces operational reliability service life service life

m N

n

n e N l N n N s n σ Q

q P p r e r σ

pressure strain ratio stress ratio temperature

t

melting temperature

m T

speed

v