Materials Science Forum Vol. 973

Abstract: The article considers features of a cutting process of stainless and heat-resistant steels and factors that determine difficulties in machining these materials. The mechanism of influence of advanced plastic deformation on the cutting process, wear of the cutting tool and formation of the quality parameters of the surface machined have been analyzed.

Abstract: A new mathematical model is proposed where breaking down of exploited drilling bits is considered to be a consequence of an unbalanced spreading of charges in drilling bit body, which is caused by the difference in interference values of obstruction in each pair “body-pick”. Fulfilled modeling allow to make a definition of complicated stress-deformed state of the drilling collet’ body with different number of teeth and different combinations of hole sizes and sizes of teeth using different materials for further production.

Abstract: The article presents the results of residual stresses measurements in the material of the internal combustion engine (ICE) sleeves. The studies have been carried out for new sleeves, sleeves after processing with diamond and single-component abrasive tools (SCAT) and sleeves that have exhausted their service life. The results of the research have established the fact that processing of the sleeves with a single-component abrasive tool substantially increases the values of internal residual compressive stresses, which contributes to the life extension of the engine in whole.

Abstract: The article presents physical regularities for the formation of the surface layer microgeometry of the parts while edge cutting machining of steels from the standpoint of the metal temperature strength and the dislocation-energy concept of the metals failure in the process of cutting. It is proposed to employ an approach that contemplates the use of the informative ability of the thermo-emf signal as an integrated index for the thermophysical properties of a workpiece and a tool in mathematical relations as per roughness parameter calculation.

Abstract: In this article we study the received quality of a welded large-diameter pipe after the processing by a single-row cylindrical brush. The speed of the brush influences the roughness of the pipe surface.

Abstract: In this work, the process of formation of a built-up edge during the cutting of hot metal rolls by rotary saws is considered. The study is conducted to increase the tool's durability.

Abstract: Results of experimental research of bending of steel sheet blanks on hammer with standard ram and ram with fillets are presented. The increasing of impact time (up to 1.5 times) and reducing of angle of springback (up to 7 times) by using of ram with fillets is obtained. Obtained data will be used for developing of optimal parameters of ram with fillets for increasing dimensional quality of produced parts.

Abstract: The subject of the research is the influence of contact interaction at the face surface on average cutting temperature at the face surface.

Abstract: In order to increase the working efficiency of coated-carbide cutting tool under interrupted cutting conditions it is most efficient to use abrasion resistant refractory coating and solid lubricants.

Abstract: The paper proposes a mathematical model of the formation of a deep-hole cut when boring it; substantiates that the cut is manifested as the technological heredity of the errors of the workpiece; confirms theoretical positions by using the method of computer simulation of the process of shaping during the finishing boring of the deep holes of hydraulic-cylinder barrels made of various steels; and introduces design and technological methods for minimizing hole errors.