Doctoral thesis information of PhD candidate Bui Thanh Hien (revised version after the Institute-level Thesis Evaluation Council):

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 external square cylindrical SKD11 steel components using CBN grinding wheels on CNC milling machines"

Summary of new conclusions of the thesis

1. Scientific significance:

- The results of the thesis make an important contribution to enhancing the understanding of the method for grinding shaped external cylindrical surfaces on CNC milling machines and determining reasonable dressing and grinding parameters, especially for grinding shaped external cylindrical surface components using CBN grinding wheels. The thesis has determined the reasonable values of dressing parameters and identified a set of reasonable grinding parameters (depth of cut, spindle speed, feed rate, and grinding wheel diameter) to ensure minimal surface roughness, high machining productivity, and simultaneous satisfaction of 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 the grinding process in general and grinding using CBN grinding wheels in particular. The information from this study can support research, serve as reference material, and also help open new research directions in grinding using CBN grinding wheels for components with shaped external cylindrical surfaces.

2. Practical significance

- The results of the thesis can be referenced and applied for grinding components with shaped external cylindrical profiles, such as shaped pellet 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 components such as pellet punches, stamping punches, etc.

- The theoretical and 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 set of reasonable technological parameters for dressing the grinding wheel (dressing depth, wheel rotation speed, feed rate), thereby using the dressed grinding wheel to grind shaped components. This study has also identified a set of reasonable grinding technological parameters for the shaped external cylindrical grinding process, such as depth of cut, spindle speed, feed rate, as well as the geometric parameter of the wheel, i.e., grinding wheel diameter, to achieve the minimum surface roughness and maximum machining productivity;

- The thesis employs a multi-criteria decision-making method using three MCDM methods: TOPSIS, MAIRCA, and 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 the minimum roughness and maximum machining productivity. This is a new 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 to grind square external cylindrical surfaces on CNC milling machines;

- The thesis provides specific guidance documents and a scientific basis for optimizing the machining process by the grinding method in general and grinding using CBN grinding wheels in particular, helping to improve the productivity and quality of the final product and save costs in the production process.

View detailed thesis information at here