The author of the paper proposed a model of joint plastic deformation of two metals in cold state. That model is based on a well-known "oxide" hypothesis. It was demonstrated experimentally that steel/ brass close contact occurs as early as at the degree of deformation 0.15–0.20, but this level of deformation is insufficient to form a compound. A close contact of metals is a necessary but insufficient condition for compounding metals in cold state. The sufficient condition for two metals compounding is the degree of deformation more than 0.50. At this deformation level juvenile metal surfaces begin entering into contact by forming adhesion bridges.

Calculation of Joint Plastic Deformation to Form Metal Compound in Cold Condition

Tube spinning technology represents a process with high forming precision and good flexibility and is increasingly being used in the manufacture of bimetal composite tubular structures. In the present study, a forming analysis of clad tube and base tube in spinning process was conducted through numerical simulations and experiments. There was an equivalent stress transition on the interface since the stress transmission was retarded from clad tube to base tube. The yield strength became a main consideration during a design bimetal composite tube. Meanwhile, the strain distributions in axial direction, tangential direction, and radial direction were also investigated to determine the deformation characteristics of each component. As the press amount increased, the strain of clad tube changed more than base tube. As the feed rate increased, the strain decreased in axial direction and tangential direction but almost unchanged in radial direction. Simultaneously, a method for controlling the wall thickness of the clad tube and the base tube is proposed. These results to guide the design of bimetal tube composite spinning process have the certain meanings.

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Analysis of the forming characteristics for Cu/Al bimetal tubes produced by the spinning process

Development of expert systems for modeling of technological process of pressure casting on the basis of artificial intelligence

The article considers the surface roughness of compression molds castings received by casting under pressure depending on the condition of the form-building surface. The technological process of casting under pressure is presented for the \"Strike plate\" product, concrete technological parameters values are specified. The pilot studies of the roughness of the castings throughout the entire period of operation of a compression mold are conducted. Based on the received values the recommendations about improvement of quality of a surface of castings by drawing sheetings are submitted by phisical vapour deposition method.

Improvement of Surface Quality of Casting Produced by Casting under Pressure

In the article various approaches to a research of the mechanism of destruction of form-building surfaces of compression molds for the casting under pressure (CUP) are considered. The main reasons for emergence of various defects of working surfaces of form-building details are defined. Method of calculation of the parameters allowing to define operability of concrete products are specified. The option of production of form-building surfaces with the raised operational characteristics drawing sheetings by method of phisical vapour deposition (PVD). is offered. Results of pilot studies on determination of optimum structure of a covering for a form-building surface are given.

Research of the Mechanism of Destruction of Compression Molds for Casting under Pressure of Color Alloys

Calculated values of joint plastic deformation for forming a connection layer of the bimetal during cold rolling. Deflection of the primary setting of the bimetal layers depends on the thickness and sizes of destruction blocks, the ratio of the geometric shapes of the blocks of the surface layer destruction, the external friction during rolling, the strip tension, the diameter of the rolls, the thickness of the bimetallic billet.

A.V. Shaparev

Papers

Calculation of the Amount of the Reduction Required for the Formation of Compound Layers during Cold Rolling of Bimetals