Diffractometer, that is, X-ray diffractometer; Characteristic X-ray and its diffraction X-ray is a kind of electromagnetic wave with a short wavelength (0.06-20nm), which can penetrate a certain thickness of substances, and can make fluorescent substances emit light, photographic camera emulsion, and gas ionization. X-rays are produced by bombarding a metal target with high-energy electron beams, which have specific wavelengths corresponding to the elements in the target, called characteristic X-rays. For example, the corresponding X-ray wavelength of the copper target is 0.154056 nm. The wavelength of X-rays is close to the spacing between the atomic planes inside the crystal, and the crystal can be used as a spatial diffraction grating of X-rays, that is, when a beam of X-rays is irradiated to the object, it is scattered by the atoms in the object, each atom produces scattered waves, and these waves interfere with each other, resulting in diffraction. As a result of the superposition of diffraction waves, the intensity of the rays increases in some directions and decreases in others. The crystal structure can be obtained by analyzing the diffraction results. This was an important scientific prediction made by the German physicist M. Laue in 1912, which was subsequently confirmed by experiments. In 1913, the British physicists W.H.Bragg and his son (W.H.Bragg, W.L.Bragg) on the basis of Laue's discovery, not only successfully determined the crystal structure of NaCl, KCl, etc., but also proposed the famous formula as the basis of crystal diffraction - Bragg equation: 2dsinθ=nλ. For crystal materials, when the crystal to be measured and the incident beam are at different angles, those crystal faces that meet Bragg diffraction will be detected, reflected in the XRD pattern is the diffraction peak with different diffraction intensity. For amorphous materials, because there is no long-range order of atom arrangement in crystal structure, there is only short-range order in a few atomic ranges, so the XRD pattern of amorphous materials is some diffuse mantels. X-ray diffractometer is the use of diffraction principle, accurate determination of the crystal structure, texture and stress of substances, accurate phase analysis, qualitative analysis, quantitative analysis. Widely used in metallurgy, petroleum, chemical industry, scientific research, aerospace, teaching, material production and other fields. X-ray diffractometer is a large analytical instrument used to study the internal microstructure of matter by X-ray diffraction principle. It is widely used in universities, colleges, research institutes and factories and mines. Common institutions with X-ray diffractometer detection capabilities are: Southwest University of Science and Technology, China University of Petroleum (Beijing), Sichuan University, Southwest Jiaotong University, Southwest Petroleum University, Tianjin University of Commerce, Zhonglan Chengguang Chemical Research Institute, Huatong Special Engineering Plastics Research Center, Nanjing University, etc. X-ray diffractometer has various forms and different uses, but its basic composition is very similar. Figure 4 is the basic structure diagram of X-ray diffractometer, and the main components include 4 parts. (1) The high stability X-ray source provides the required X-ray for measurement. Changing the anode target material of the X-ray tube can change the wavelength of the X-ray, and adjusting the anode voltage can control the intensity of the X-ray source. (2) The sample and the adjustment mechanism of the sample position orientation system The sample must be a solid block of single crystal, powder, polycrystalline or microcrystalline. (3) The X-ray detector detects the diffraction intensity or simultaneously detects the diffraction direction, and the polycrystalline diffraction pattern data can be obtained through the instrument measurement recording system or the computer processing system. (4) Diffraction pattern processing and analysis system Modern X-ray diffractometers are equipped with special diffraction pattern processing and analysis software of the computer system, they are characterized by automation and intelligence.