Design And Experimental Research Of An Nano-indentation Testing Device

The mechanical properties of the material directly affect their performance stability and reliability during use. The failure of materials and their products are mainly from the micro-deformation, micro-injury and defect. In order to systematically analyze the micro deformation damage mechanism of materials under load, domestic and foreign scholars have put a lot effort into the research of related test methods and technique. As the nano-indentation technique has the advantages of high precision, the rich information of materials mechanical properties and easy preparation of sample. With the development of electron microscopy, Raman spectroscopy and X ray technology, nano-indentation testing technology came into being. This new technology has the advantages and characteristics of nano-indentation testing technology, with which can dynamically test and analyze the mechanical behavior, damage mechanism and microstructure structure evolution of materials under indentation loads. This research has received extensive attention from the international academic community in recent yearsExisting problems of indentation testing instruments at home and abroad were compared on the basis of studying the current situation of domestic and foreign researches. The nano indentation testing was realized by combined the requirements and objectives in the situation of multiple loads and physic field coupling preload. The integrated analysis, debugging, calibration and design of nano-indentation device under specific working conditions were carried out. On this basis, experiments for the indentation response of typical materials were developed using the test equipment after the calibration. The main contents of this dissertation are summarized as follows:(1)On the basis of studying the present situation of the nano indentation testing technology, the advantages and disadvantages of the existing nano indentation testing instruments were summarized, the development trend and prospect of indentation testing technology was forecasted.(2)The classical data analysis methods for nano-indentation—Olive&Pharr was analyzed. Regard this method as the theoretical basis, the precision drive and detection technology were analyzed and narrated in this paper. The mechanical properties of key parts of the indentation flexible hinge were analyzed and calculated, and the typical of the common indenter was introduced.(3)The design and analysis of in situ nano-indentation tester was carried out. Combined the nano indentation testing technology and multi load testing machine organically.3D modeling was built by combing the technology with in-situ test. Calibration and analysis of typical materials indentation response were carried out on this basis with the calibrated testing instrument.(4)Force and displacement sensor were calibrated, the factors which could affect the testing device’s repeatability and accuracy were analyzed and the instrument precision was adjusted. Typical materials indentation response testing experiment was also carried out.