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RUSSIAN |
To provide quality of processed surface with achievement of maximum possible productivity of machining is a very important task, which is solved at the stage of planning technological processes of detail manufacturing. One of the ways to increase productivity is to choose optimum parameters of cutting process. In the connection with this the research on the optimal cutting modes, providing the maximum productivity for the given machining conditions and requirements to the quality of machined surfaces, is very actual.
Creation and effective application of new superhard materials are one of the main pre-conditions to increase details quality and machining precision of hard-processed construction materials. In this connection, optimization of machining processes using superhard tools is very actual.
The purpose of this research is to increase quality of a superficial layer and to rise efficiency of detail machining with the help of approved choice of machining technological methods and also to work out recommendations on the cutting modes choices.
Basic tasks of research are:
1. Theoretical research of the superficial layer formation on the details of "rotation body" type and technological possibilities analysis of the final turning method.
2. Forecasting of operating properties of "rotation body" type details judging from cutting modes during the machining of external surfaces of rotation.
3. Analysis of experimental data and machining parameters influence on the roughness during turning with the help of tools, which are equipped with synthetic superhard materials (SHM).
4. Working out recommendations on the cutting modes choices which help to obtain mostly economically necessary parameters of superficial layer state of "rotation body" type details.
5. Calculation of superficial layer parameters of "rotation body" type details on the base of mathematical programs package MathCAD 2001 Professional taking into account their operating properties.
Technological features of the SHM tools effective application are caused by their physics-mechanical properties and high cost. SHM are inferior to the hard alloys on durability, but they have considerable advantages on hardness and heat-resistance, which determine their high wearproofness when they operate with high cutting speeds and unstressed loading. Cutting tools are designed for fine and semifine machining of details made of cast-iron, hard-tempered steel, non-ferrous alloys (on the copper basis) on the special machine-tools, CNC machine-tools and flexible production modules in the conditions of the automated manufacturing. Superhard cutters are most effective to machine the cast-iron details.
In this work we use cutting tools with elboron plates. Elboron is a unique instrumental material which combines high hardness with high heat-resistance (elboron’s 1300°С comparer with diamond’s 650°C) and chemical sluggishness. Due to these properties elboron tools are considerably more effective than diamond ones during machining of tempered steel, heatproof and titanic alloys. High cost of elboron tools is exceeded by higher firmness and spoilage absence.
In this research the analysis of existent methods of increasing details surfaces quality has been made, including ecologically clean technological methods on the basis of new high-speed machining methods.
Possibility and financial ability to achieve this level of properties has been proved by using progressive machining methods – final turning.
We have also considered the actual issues connected with superhard material application, including new instrumental material brands, tool constructions and modes of their usage.