Getting Oil Pipes High Strength Quenched and Tempered Condition

The use of the steel with low carbon and fine grain Cr-Mo type is asked by the necessity to fit high strength and plasticity characteristics. The paper emphasizes the quenched and tempered high strength pipes from groups II, III and IV � API 5 CT obtaining. The laboratory experiments followed the establishment of optimum values of the heat treatment parameters. Saying all these to ensure the obtaining of the mechanical characteristics specific to eachs grade that was to be obtained. Were used microalloyied steels with vanadium and columbium, that refined the structure of improved the materials toughness. The paper is determined hardenability and finishing elements influence the use of grain (V, Nb) on hardenability.

Влияние поверхностного слоя на комплекс свойств тонкой проволоки из сплава на основе TiNi

We have studied the influence of the surface layer on the parameters of the multiply repeated shape memory effect, developing stresses, characteristic temperatures, and intervals of martensitic transformations in thin (1 mm diameter) wires made of TiNi-based alloys. Examination of the surface layer structure showed that, in 1-mm-diameter TN-1V grade alloy wire, the oxide layer is about 15 μm thick and consists mostly of titanium, nickel, oxygen, and carbon. Removal of this surface layer leads to an increase in the maximum accumulated deformation, shift of the temperature interval of formation toward higher temperatures, and increase in the strength and plasticity characteristics.

Increasing the Mechanical Properties of FCC- and BCC-Metals by Combined Cold Severe Plastic Deformation

It is shown that the twist hydroextrusion results in the formation of fine crystalline structure with grains of elliptical shape oriented at an angle of ≈450 to the axis of deformation. Mechanical properties of the processed copper are characterized by a high level of strength and plasticity characteristics. Peculiarities of the formed structure are inherited under the subsequent rolling, they are in untypical location of grains relative to the axis of deformation.

Influence of hard cold working on microstructure and properties of annealing copper tubes

This work gives results of influence of temperature and deformation degree on changes in the metal grain growth of drawn copper tubes, because this mutual dependence was observed. Copper tubes samples, chemical content of 99,97 % Cu and 0,024 % P, were exposed to recrystallized annealing after drawing. The annealing was carried out at temperatures of 573, 623, 673, 723, 773, 823 and 873 K, for 60 minutes, in laboratory conditions. Investigation results show that after drawing with high cold deformation degree (96 - 99 %), the annealing leads to the changes in the continuous grain growth with increased temperature. The smaller grain size appears at 823 K in comparison with the lower annealing temperature. Annealing has influence on mechanical characteristics of tested samples and during drawing of copper tubes these characteristics are adequately changed: with regard to the annealing at the 773 K, the characteristics of strength and plasticity increase as a result of decreased grain size. The increase of annealing temperature to 873 K leads to the increased grain size and decreased values of strength and plasticity characteristics.