Metal Science and Heat Treatment

Mints, R.; Petukhova, T.; Segal, V.

doi: 10.1007/BF00648448pmid: N/A

Lysak, L.; Andrushchik, L.

doi: 10.1007/BF00648449pmid: N/A

1. The first stage of martensite decomposition is two-phase in rhenium steels with 0.3–1.4% C and 10–20% Re, and three-phase in steels with 1.6–1.7% C and 3–6% Re. 2. Increasing the carbon and rhenium concentrations of the steel lowers the rate of the first stage of decomposition. 3. With increasing concentrations of carbon in the steel the tetragonality of the ϰ martensite lattice increases, as a result of the larger elastic deformation of the lattice resulting from coherence with the lattice of precipitates rich in carbon.

Kidin, I.; Shcherbedinskii, G.; Andryushechkin, V.; Volkov, V.

doi: 10.1007/BF00648450pmid: N/A

Sokolov, K.; Éntin, R.; Khlestov, V.; Betin, G.; Kogan, L.; Konopleva, E.

doi: 10.1007/BF00648451pmid: N/A

Gol'dshtein, V.; Verbovetskaya, D.

doi: 10.1007/BF00648452pmid: N/A

1. The recrystallization nuclei formed in different sections of the deformed matrix have different orientations: a) the nuclei formed in the boundaries of the original grains have the orientation of one of the neighboring grains in the matrix; b) the orientation of nuclei formed in microbands is close to that of the grains in the matrix before deformation; c) the nuclei formed near coarse particles of second phase promote scattering of the recrystallization texture. 2. To ensure a structure and texture in automobile sheet that improves the drawability, recrystallization must occur in a fine-grained matrix not containing large particles of second phase, and characterized by strong component (111) [UVW]. 3. Rocker annealing leads to the structural and textural changes that improve the properties of the sheet.

Lobl, K.; Tuma, G.

doi: 10.1007/BF00648453pmid: N/A

Apaev, B.; Voronenko, B.

doi: 10.1007/BF00648454pmid: N/A

Geveling, N.; Maslenkov, S.

doi: 10.1007/BF00648455pmid: N/A

1. In hypoeutectic and hypereutectic Ni−Cr alloys with compositions close to the eutectic the nucleation of primary dendrites of α phase is observed primarily in the bulk of the melt. On the contrary, γ phase nucleates on the cooling surface of the ingot and occasionally on primary dendrites of α phase. 2. In comparison with the eutectic composition, the solidification of the eutectic in alloys rich in chromium occurs only after formation of γ phase borders around primary dendrites of α phase. With deviations of the composition from the eutectic to the chromium side the structure consists of dendrites and eutectic, and in alloys on the nickel side the eutectic structure degenerates. 3. Excess primary crystals of α and γ phase are characterized by a higher degree of supersaturation with the second component than the same phases solidifying in eutectic colonies. In comparison with equilibrium values, the relative supersaturation for primary and eutectic crystals of α phase is higher than for crystals of γ phase. 4. The character and intensity of decomposition in solid phases of alloys of the eutectic type are due to the type of solidification and the corresponding supersaturation with second component. The rate of decomposition is highest in dendrites and primary crystals, and slow in crystals of phases forming eutectic colonies because of the small supersaturation.

Petropavlovskaya, Z.

doi: 10.1007/BF00648456pmid: N/A

1. To obtain high relaxation resistance, solid solutions based on iron or nickel must be alloyed with elements that increase the elastic characteristics of the lattice and form thermally stable hardening phases. 2. Multicomponent alloying of solid solutions based on iron and nickel with niobium, molybdenum, and tungsten is the most effective, the maximum hardening being attained at lower concentrations of the alloying elements as compared with binary solid solutions. 3. The presence of hardening phases increases the strength and relaxation resistance only if they are highly dispersed in the solid solution with high elastic properties.

Tsvetaev, A.; Balakhovskii, O.; Chuzhko, R.; Grishina, S.

doi: 10.1007/BF00648457pmid: N/A

From comparison of the strength characteristics of the Rh-Re alloy and pyrolytic tungsten in vacuum at elevated temperatures it can be seen that the alloy of rhodium with 18% Re is less susceptible to softening and more highly resistant to creep at relatively high stresses and temperatures around 1000°C.