A kutatási téma leírása:
Although there are great efforts and demands for introducing 3D printing technologies in the production, mechanical chip removal processes will surely remain a crucial manufacturing method for decades. The reason for that is the limited capability of additive technologies regarding surface quality, geometric accuracy, and economic production cost in large scale production of metallic parts. In the modern manufacturing the request for part miniaturization is continuously increasing. Besides that, new, extreme technological tasks become increasingly important to be solved, such as machining hardened steels and super alloys. Both micro machining and ultra precision machining realise thin – even only some microns – chip removal process. The real chip thickness is influenced by the properties of the workpiece material, tool geometry, and its tool edge radius, which depends also on its actual wear state. There are unique circumstances and special processes of material separation at micro machining because of the size effect, which requires the development of chip removal models. Temperature plays an essential role in material in structural changes, in decreased machining quality, and in tool degradation. To avoid these problems, effects of different cooling and lubricating methods at micro chip removal processes have to be investigated in detail.
2. Aim of the research
The motivation and main aim of this research work is the detailed practical and theoretical investigation of thin chip removal methods to understand the characteristic circumstances of material deformation and thermal processes because of the size effect. New analytical and numerical model will be introduced, which takes also the thermal and tribological effects at micro chip removal processes. Optimal cutting parameters will be available at micro machining of hard materials. Effects of cutting fluids will be investigated in detail.
3. Tasks, time necessary
Literature survey regarding thin chip removal processes, focusing on machining of hard materials (1st semester).
Summarizing the models of micro chip removal processes and hard turning. Evaluation of available models (2nd semester). Summary of literature survey in written form. Improvement of analytic models of thin chip removal process and hard cutting considering special thermal and tribological effects, and tool wear. Specification and set-up of measurement system for recording machining data. Specification of workpiece materials and cutting parameters. Design of experiments (3rd and 4th semesters).
Investigation of dynamic effects at thin chip removal processes and hard machining. FEM modelling Preliminary cutting experiments (3rd and 4th semesters).
Experiments about thin chip removal processes. Verification of FEM and analytic models (5th and 6th semesters)
Creating mathematical models of thin chip removal process considering special thermal, tribological, and wear processes (5th, 6th and 7th semesters).
Determination of optimal cutting parameters at thin chip removal process of hard materials (6th and 7th semesters).
Publication of the results (between 3rd and 8th semesters)
Preparing and finishing of scientific thesis (7th and 8th semesters)
4. Necessary equipment
Micro milling center, ultra precision tuning lathe, force and vibration sensors, digital and confocal microscopes, surface roughness measuring units, evaluation software, FEM software are required, which are available at the department, or at partner departments.
5. Expected scientific results
The unique specialties of thin chip removal processes will be presented, first of all in the case of machining of hardened surfaces and miniature geometrical structures. Detailed model of the cutting processes at thin chip removal and hard cutting will be created considering special tribological, thermal and wear processes. Optimal cutting parameters will be available for micro machining of hard surfaces.
J C, Jáuregui ; J R, Reséndiz ; S, Thenozhi ; T, Szalay ; Á, Jacsó ; M, Takács: Frequency and Time-Frequency Analysis of Cutting Force and Vibration Signals for Tool Condition Monitoring, IEEE ACCESS 6 pp. 6400-6410., 11 p. (2018)
Marton, Takacs ; Balázs, Zsolt Farkas: Theoretical and Experimental Investigation of Machining of AISI H13 Steel, ADVANCED MATERIALS RESEARCH 818 pp. 187-192, 6 p. (2013)
M Takács, B Verő: Actual Feed Rate per Tooth at Micro Milling, MATERIALS SCIENCE FORUM 537-538, 2007, pp. 695-700.
Takács M, Verő B: Material Structural Aspects of Micro-Scale Chip Removal, MATERIALS SCIENCE FORUM 414-415, 2003, pp. 337-342.
M Takács, B Verő, I Mészáros: Micromilling of Metallic Materials, JOURNAL OF MATERIALS PROCESSING TECHNOLOGY 138, 2003, pp. 152-155.
ajánlott nyelvtudás (magyar oldal): english
felvehető hallgatók száma: 1
Jelentkezési határidő: 2021-03-23