Science of materials and mechanical Engineering

The Choice of Exploitation Parameters of Bearing Materials Based Made of Tool High-Speed Steel Based on the Friction Films Analysis

This study presents the research results of secondary structure films of bearing materials made of tool high-speed steels Р6М5, Р6М5К5, Р6М5Ф3 abrasive wastes with the solid lubricant CaF2. They are formed on the contact surfaces at friction under hard exploitation conditions and influence functional properties of the friction unit. We also demonstrate the possibility of forecasting the necessary level of antifriction properties by creating films of the required depth and chemical composition as well as justify setting the materials exploitation parameters.

Diffusion coating with titan in aluminum and 12x18h10t nitrated steel

This study reveals the results of comprehensive treatment of 12X18H10T steel. We demonstrate the possibility of combining nitrating steel in the ammonia medium at a temperature 540 °С for 20 hours followed by titanium alumunizing relying on the powder method in containers with the consumable gate under the reduced pressure at a temperature 1050 °С for 0,5–6 hours. In addition, we examine the structure, phase and chemical composition of the obtained coatings. Finally, we describe the influence of nitrating on formation of the surface barrier layer of titanium nitride TiN.

The Corrosion Resistance of Chrome-calorized Steel 12Х18N10T

The paper under scrutiny presents the research results of chrome-calorized steel 12Х18N10T. Moreover, we demonstrate that it is possible to obtain complex chrome-calorized coating with titanium nitride TiN on the surface of the steel 12Х18N10T. To obtain this coating, we combine two processes: physical vapor deposition of titanium nitride and diffusion of chrome-calorizing conducted through the powder method in containers with fusible gate under reduced pressure at 1050 C for 3 hours. Hence we obtain the structure, phase and chemical composition of coatings.

A Process of the Laminar Convectional Mixing of Fibroconcrete is at Vibroextrusion in Round Circular Channel

We clarify features of the process that occurs in a round circular channel to assess the degree of the components mixing in fiber-reinforced concrete compositions in a modern vibroextruders. We also consider the process of simple mixing in a laminar flow in the absence of diffusion occurring in such a channel. When reviewing the process we utilize the phenomenological approach, which takes the fiber-reinforced concrete composition for a homogeneous isotropic medium. We solely generalize explanations on the composition structure.

The Generalized form of the Momentum Conservation Law in Classic Mechanics

We obtain the generalized form of the momentum conservation law from the energy conservation law for the closed mechanical system. This form reflects the simultaneous change of speeds and accelerations of forward and rotatory motions under the interaction and loading of finite bodies and meets the condition of power balance of forces and moments. We show that laws of forward and rotatory motions conservation in traditional Newton-Euler representation are particular cases of the formulated generalized form.

Testing Centrifugal Filter and Cyclofilter with Widespread Ash Solid Fuel Boiler

The paper presents the results of bench tests of the centrifugal filter and cyclofilter and further settlement and comparative analysis of these devices with the most common in the former USSR typical NDIOHAZ cyclones. Relying on a single technique, we conduct the comparative testing of centrifugal filter CF1-6-0,15 and cyclofilter in the laboratory of the Institute of Engineering Thermophysics under the NAS of Ukraine. We employ ash as a contaminating material deposited behind the BKZ-220-140-Hz boiler economizer of the Cherkasy TPP and sampled during the boiler blowing-out.

The Experimental Study of Detachable and Attachable Flow Limits of Liquid Film on the External Surface of Rotating Cone

The paper studies detachable and attachable flow limits of liquid film on the external surface of the rotating cone with different angles at the foundation (from 30 to 55 degrees) in the range from 400 to 1700 rpm with the fluid flow up to 45,2 g/s. The film flow in the lift-off zone looks like radial convex streams, from which droplets are falling. The bulk of the liquid flame spray is formed. The angle cosine at the cone base influences the most the beginning of droplets falling from the film surface.

The Application of C Involute Gearing in the Escalator Drive

The subject-matter of our research is transport vehicles with a chain pulling device with an intermediate drive location. Specifically, the paper considers the engagement of the drive sprocket with a pull chain performing the function of cogging and discusses the features of cogging kinematics. We also identify overlapping factors and calculate gearing contact stresses.

Definition of Mixing Time for the Closed Type Mixer with Oval Rotors

This paper deals with the design procedure of mixing time of polymer or rubber mixtures taking into account its movement not only in circular, but also in an axial direction of a mixing chamber. The preliminary comparison of theoretical and experimental data shows the possibility of implementing the developed technique.

The increase of hydroabrasive wear resistant of the high-alloyed white cast-iron

In this paper, we study the influence of chrome, manganese and nickel on hardness and wearproof of white cast-irons, assigned for making the poured detail parts of dredging pumps of the systems of ash hydro-disposa thermal electric power station. We optimize the microalloying technology using titan, vanadium, antimony and modification of chrome-manganese cast-iron by boron to improve its special properties.