Metalloobrabotka № 2 (98)/2017

Mikhailov S. V., Kovelenov N. Yu., Bolotskih S. V. Aspects of designing and selecting the indexable cutting inserts with curved rake

The paper describes the current status of the problem of designing and selecting the insert-based tools for machining ductile materials. Authors review the development milestones of the theory for designing the indexable cutting inserts with chip curler rake features. Based on research into the aspects of cutting with curvedrake tool, the paper presents the method for calculating the main parameters and design algorithm for developing indexable cutting inserts that meet process requirements.

Keywords: material cutting, tool design, indexable faceted cutting inserts, chip breaking.

Danilin G. A., Filin D. S., Voljin S. G. Technological features of process longitudinal double-sided extrusion of hollow parts

Provides basic information on the combined process about Dolny double-sided extrusion. The similarity with the process of drawing-extruding and given the variants of implementation of the process. The main factors influencing the technological parameters and the regularities of their influence on the security mode. Shows a General picture of the distribution of the parameters of the stress-strain state on the outer and inner surfaces of the workpiece.

Keywords: cold stamping, combined extrusion; technological strength; stress-strained condition.

Lobov V. A., Danilin G. A. Improving the quality of the surface layer of the metal during forming hollow flanged products

The influence of the sizes of the workpiece and the tool on the unevenness strain-effective in cross-section during drawing with wall thinning on the inner contour. According to the results of computer simulation and experiment set linear law of variation of the straineffective in wall thickness. Mathematical models were developed of forecasting a linear strain distribution coefficients. Formulated deformation criterion of the surface layer of the metal strength.

Keywords: drawing with thinning, inner contour, unevenness, strain-effective, mathematical model, strength, prediction.

Danilin G. A., Zaterukha E. V. Forecasting of characteristics of the mechanical properties of parts manufactured by cold punching

In the article the actual problem of maintenance of operational requirements on mechanical properties of loaded metal elements of an ammunition is solved. A multilevel structure of the process model for manufacturing shells with the use of methods of pressure treatment and heat treatment is proposed. Performing calculations of the mechanical properties of the sleeves in the controlled design sections according to the developed mathematical models.

Keywords: prognosis, degree of deformation, technological cycle, technological process, mechanical properties.

Danilin G. A., Vinnik P. M., Remshev E. U., Zaterukha E. V. The calculation of the strain-effective in the part made hood with wall thinning taking into account variation in wall thickness

A characteristic feature of the stamping methods of drawing with thinning of the parts is the presence of thickness variation in the cross sections, which may make up 10-25%, and in some cases exceeds these values. The proposed analytical estimation of the effect of thickness variation on the value of the degree of deformation in the hood with thinning.

Keywords: strain-effective, hood with thinning, variation in wall thickness in cross section.

Gavze A. L. Mechanical properties and processingbehavior of nitrogen mold heat treatable steel for production of loaded structures for transport engineering

The article reviews research results for mechanical properties and processing behavior of samples of experimental casts of 30Cr3MnMoNV mold steel. Mechanical properties of steel were determined at tensile and impact bending after heat treatment various modes. Undercooled steel austenite stability at isothermal transformation and continuous cooling was evaluated. Critical constants of steel during heating were determined using the dilatometric method. Computational methods were used for determination of casts martensitic transformation onset temperature and ideal diameter of experimental steel tempering. Heating temperature effect on austenite grain size of experimental steel was determined. Advantage of mechanical properties and process behavior of experimental steel over performance of commercial cats steel grades was defined.

Keywords: Experimental casts, mechanical properties, grain size, critical constants, austenite stability, hardness penetration, heat treatment.

Maksarov V. V., Vyushin R. V, Efimov A. E. Technological maintenance of surface roughness based on the modeling of transient processes

In presented article deals with the issues related to the provision of the roughness of the surface layer parts «stock» in technological process, at the expense of management and forecasting on stages of the machining process dynamic stability through means of mathematical modeling of the system in view of the transition process.The role of the transition process performs a preliminary

method of local thermal influence on the surface layer of the workpiece in the intended area removes allowance, which due to switch introduces into the a mathematical model of a metastable structure that is different from the base metal on the physical and mechanical properties. For analysis of the effect of pre-established local metastability in the processed material on the dynamic properties of the technological system adopted single-loop mathematical model describing the delay in changing the cutting forces, leading to the emergence of self-oscillation process. Based on the results of mathematical modeling in software environment NILabVIEW 2013 established that at step mechanical processing happening sustainable suppression of oscillations arising during the passage of the zone with metastable structure. The positive effect on the suppression of vibrations confirmed experimental study where the deviation from the theoretical value of 17 ...23%. Suppression of self-oscillation process, in turn, provides necessary surface roughness and allows the cut in the current technological process grinding operation, increasing productivity and expanding operating parameters mechanical processing.

Keywords: technological process, mathematical modeling, the local thermal influence, metastability, technological system mechanical processing, a selfoscillating process, parameters roughness.

Ageev S. V., Girshov V. L., Zemenko V. N. Hot isostatic pressing of bimetallic bars with an outer layer of powder high-speed steel

Presents the results of research obtained in the development of the technology of hot isostatic pressing of bimetallic bars with an outer layer of high speed steel powder in a sealed capsule with a titanium getter. Characteristics of microstructure and properties of the compact metal are given. Made an experimental batch of bimetal hobs and rolling rollers with high wear resistance Keywords: hot pressing, high speed steel, powder, bimetal, cutters, rolling casters.

Karatushin S. I., Bokuchava P. N., Khramova D. A., Pehov V. A. Simulation of stress-strain state of disc springs

When manufacturing parts Cold forming methods in the latter are almost always formed residual stresses (RS). The cause of these tensions is the inhomogeneous deformation of the product by volume. The consequence of cold working is not only hardening by dislocation mechanism, but RS that will emerge from the stresses of the external load. Effect of cold forming on the stressstrain

state (SSS) is considered by the example of the Belleville spring from b-titanium alloy. A comparison of VAT under a load of dishes without RS and RS. It was found that the VAT in contact with the dishes it is characterized by a significant level of tensile stress exceeding the elastic limit in case of overload. When cyclic variation of the load voltage in contact vary in a symmetric cycle. VAT contact plates without it characterizes otnulevym cycle at lower voltages.

Keywords: disc spring, the stress-strain state (SSS), the residual voltage (RS), contact stresses, ANSYS.