Metal Science and Heat Treatment

Volgunin, A.; Lysenko, V.

doi: 10.1007/BF00712454pmid: N/A

Zinov'eva, G.; Semenchenko, M.; Malygina, T.

doi: 10.1007/BF00712455pmid: N/A

Kudryavtseva, G.; Danilova, I.

doi: 10.1007/BF00712456pmid: N/A

1. The use of steels R9K10, R9M4K8, and R3M3F4K5 made it possible to increase the life of sectional hobbing cutters. 2. During the heat treatment of the new complexly alloyed high-speed W-Mo-V-Co steels it is indispensable systematically to check the operation of the salt baths in which the steel is heated before hardening, and thoroughly to check the quality of the heat treatment of the tool. 3. If in the molten salts a magnesium fluoride rectifier with an addition of 0.2% black amorphous boron is used, the decarburizing activity of the baths can be greatly reduced and the quality of the tools improved. 4. The good results obtained in tests of tools made of experimental melts of steel R3M3F4K5 indicate that it is an advantage to make tools from this steel.

Gur'eva, Z.; Semenchenko, M.

doi: 10.1007/BF00712457pmid: N/A

The heating of stuffing-box springs coiled in the cold state causes their elastic properties in operation to deteriorate, and this deterioration is the greater, the higher the temperature to which they are heated. 2. The established dependence of the decrease in rigidity on the temperature makes it possible to predict the magnitude of the decrease of operating internal forces upon heating of springs that did not receive stabilization heat treatment. 3. To improve the operating reliability, springs after coiling must be thermally stabilized, and the stabilization temperature is chosen in dependence on the requirements that their rigidity must meet.

Gliner, R.

doi: 10.1007/BF00712458pmid: N/A

Belousov, V.; Zhigun, A.; Kolesov, S.; Skoblo, A.

doi: 10.1007/BF00712459pmid: N/A

Skoblo, A.; Zhigun, A.; Kolesov, S.; Dunia, L.

doi: 10.1007/BF00712460pmid: N/A

Lipchina, A.; Nemanov, A.; Stratinskaya, L.

doi: 10.1007/BF00712461pmid: N/A

1. The basic reason for anomalous grain growth in 42KhMFA steel in heating to 900–1000°C is not the melting method but the solidification conditions promoting the occurrence of macro- and microchemical inhomogeneities causing nonuniformity in second-phase particle distribution. 2. Different production methods of melting, forging, and rolling with small degrees of deformation do not change the tendency of 42KhMFA steel to mixed grain size in heating to 900–1000°C. 3. The greatest degree of mixed grain size is observed in heating case 42KhMFA-ÉSR steel (retarded cooling of the ingot) to 960°C but it is almost completely absent with the same heating of samples from an ingot rapidly cooled in solidification. 4. Forging with a large degree of reduction and subsequent annealing eliminates the tendency toward the occurrence of mixed grain size in 42KhMFA steel in heating to 900–1000° C regardless of the method of melting it as a result of the more uniform distribution of second-phase barrier particles on the grain boundaries. 5. The formation of ruptures in the austenitic grain boundaries and the dispersion of the brain boundaries in heating probably occur as a result of the appearance of annealing twins in areas free of barrier particles (carbonitrides, oxides, etc.).

Bogdanov, V.; Goritskii, V.; Zvezdin, Yu.

doi: 10.1007/BF00712462pmid: N/A

1. Increasing the phosphorous content in 10KhN1M steel from 0.010 to 0.044% is accompanied by a significant increase in its tendency toward thermal embrittlement after hardening and tempering. The intensity of the increase in the brittleness transition temperature is significantly less for 10KhN1M steel than for 10KhSND steel. 2. The increase in the brittleness transition temperature is related to the increase in the share of intersubgranular—intergranular component in the brittle zone of the fracture. In the steel with 0.044% P the brittle fracture occurs preferentially in the former austenitic grain boundaries and in the steel with a lower (0.010%) phosphorous content primarily intersubgranular fracture is observed.

Balychev, Yu.; Tkachenko, F.

doi: 10.1007/BF00712463pmid: N/A

1. Tempering at 550–650°C leads to refinement of the structure and a change in the phase composition of hardened G8 steel. 2. As a result of tempering at 600–650°C ε-phase, the quantity of which depends upon the tempering temperature and time, is formed in G8 steel.