Internal friction, plastic properties, and impact toughness of V-Ti-Cr alloys

Investigation of oxygen-titanium interaction in vanadium by internal friction method

“…These problems gave rise to numerous studies devoted to investigating the relation between the embrittle ment processes and physico mechanical properties of bcc metals [5][6][7]. Thus, upon investigating the EK 181 ferritic martensitic steel and V-4Cr-4Ti alloy, the correlation between the change in the impact duc tility and the amplitude independent internal friction [6] was established; this fact confirms the important role of impurities in the embrittlement of bcc materials [1].…”

“…However, as well as for other bcc materials, the main problem of their practical use is low temperature radiation embrittlement and an increase of the brittle ductile transition temperature under irradiation [1,5]. These problems gave rise to numerous studies devoted to investigating the relation between the embrittle ment processes and physico mechanical properties of bcc metals [5][6][7].…”

Multi-directional forge molding as a promising method of enhancement of mechanical properties of V–4Ti–4Cr alloys

“…Here G % 50 GPa is the shear modulus for vanadium [6,7]; b % 0.262 nm is the Burgers vector of the dislocation [8]; k % R(2p/3f) 1/2 is the distance between the particles. The calculated values of Dr presented in Table 2 are obtained for low volume contents (f ( 50%) of the second phase that can be realized for different technology [6,7] alloys with different concentrations of oxygen, carbon, and nitrogen, produced in Japan (f % 0.16%), Russia, (f % 0.24%), and the USA (f % 0.30%) that we investigated previously [3].…”

Cold brittleness of metals as a structural multistage dislocation process

“…The problem of cold brittleness and fracture resistance of metals (alloys, steels) has been studied for a long time [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16], but is still pending for low temperature application of metals (products), including structural materials for nuclear and nuclear fusion reactors. Cold brittleness and fracture resistance of metals (products) is determined by the occurrence of low temperature embrittlement (generation of ductile-brittle transition temperature T dbtt ) in certain conditions (temperature, stress), initiation and propagation of subcritical and critical cracking and brittle failure at T < T dbtt and external stresses lower than the metal yield strengths.…”

“…Here, L is a fracture half-length, E is and elastic modulus of metal, γ is the specific surface energy of metal, σ is the normal stress to the crack plane. Coefficient value α ≈ 1 is defined by the current geometry and metal (product) stress condition [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. For further investigations of metal cold brittleness, Griffith condition includes only some corrections (adjustment of α) that take into account metal geometry, crack front shape, plastic zone and possible critical crack opening mechanisms [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16].…”