National Research Institute of Mechanical Engineering plans to organize the Institute-level PhD thesis evaluation council for PhD candidate Bui Thanh Hien in early October 2024. The Institute hereby announces the information of the candidate's PhD thesis as follows:

Full name of PhD candidate: Bui Thanh Hien

Supervisors: Prof. Dr. Vu Ngoc Pi and Dr. Vu Van Khoa

Field: Mechanical Engineering - Code: 9520103

Training institution: National Research Institute of Mechanical Engineering - Ministry of Industry and Trade

Thesis title: "Research on determining reasonable grinding parameters for SKD11 steel square external cylindrical parts using CBN grinding wheel on CNC milling machine"

Summary of new conclusions of the thesis

1. Scientific significance:

- The results of the thesis make an important contribution to improving understanding of the method of shaped external cylindrical surface grinding on CNC milling machines and determining reasonable dressing and grinding parameters, especially for grinding shaped external cylindrical surface parts using CBN grinding wheels. The thesis has determined the reasonable values of dressing parameters, identified a set of reasonable grinding parameter values (depth of cut, spindle speed, grinding wheel feed rate, and grinding wheel diameter) to ensure low surface roughness values, ensure high machining productivity, and simultaneously ensure both criteria. This provides valuable information for optimizing the grinding process using CBN grinding wheels;

- The research results have contributed to the development and optimization of grinding methods in general and grinding using CBN grinding wheels in particular. The information from this study can support research, serve as reference materials, and also help open new research directions in the field of grinding using CBN grinding wheels for machining parts with shaped external cylindrical surfaces.

2. Practical significance

- The results of the thesis can be referenced and applied for grinding parts with shaped external cylindrical profiles such as shaped compression punches, shaped sheet metal stamping punches, etc., using CBN grinding wheels on CNC milling machines. This is an effective solution to increase productivity and quality when finishing or final machining shaped external cylindrical parts such as compression punches, stamping punches, etc.;

- The theoretical combined with experimental research method presented in the thesis can be used as a reference for scientific research and technical training in the field of mechanical processing in general and for those interested in grinding technology using CBN grinding wheels in particular.

3. New contributions of the thesis

- Through the use of modern mathematical tools, this study has identified a reasonable set of technological parameters for dressing (dressing depth, wheel rotation speed, feed rate) and then using the dressed grinding wheel to machine shaped parts. This study has also identified a reasonable set of grinding technological parameters for the shaped external cylindrical grinding process such as depth of cut, spindle speed, wheel feed rate, as well as the geometric parameter of the wheel, namely grinding wheel diameter, to achieve the minimum surface roughness and maximum machining productivity;

- The thesis applies the multi-criteria decision-making method with three MCDM methods: TOPSIS, MAIRCA, EARM combined with two weighting methods MEREC and Entropy in the field of grinding technology. The result of the thesis is the identification of a set of reasonable grinding parameters to simultaneously achieve minimum roughness and maximum machining productivity. This is a novel application in the field of precision machining and can be applied to similar studies in this field;

- The thesis makes a significant contribution to the development and expansion of grinding technology, supplementing specialized knowledge about grinding on CNC milling machines using CBN wheels, and especially the method of using CBN grinding wheels for grinding square external cylindrical surfaces on CNC milling machines;

- The thesis provides detailed guidelines and a scientific basis for optimizing the grinding process in general and grinding using CBN grinding wheels in particular, helping to improve productivity, quality of final products, and save costs in the production process.

Detailed information of the Thesis can be found here