China's pioneer of metal texture theory.
Yan has long been committed to the research of physical metallography and material science. As early as 1944, he undertook the work of building a materials laboratory in the Central Industrial Laboratory, conducting structural steel tests and studying the mechanical properties of bamboo.
1947, when Yan graduated from Yale University in the United States, he submitted a paper entitled "Study on Deformation Texture in Metals", which was published in the Journal of the American Society of Mining and Metallurgy Engineers. In this paper, he put forward a unique view, and calculated the slip system and processing texture of three commonly used crystal systems simultaneously by theoretical analysis method for the first time, which attracted the attention of scholars in metallurgical circles in many countries, and was listed as one of the more complete and successful texture formation theories by scholars in Britain, the United States, Germany and other countries in texture monographs, which had a certain impact on the study of metal processing texture. During the period of 1948, Yan made new progress in the experimental study of transverse bending of aluminum single crystals, made new discoveries and understandings of uneven deformation of crystals, and put forward a new hypothesis of micro-bending of plastic deformation of crystals.
When Yan studied the recrystallization texture of pure copper in the research department of Datong Copper Processing Factory in the United States, he applied the X-ray grazing method to the determination of texture, studied the influence of trace impurity phosphorus on recrystallization texture in solid solution and compound state, and put forward unique opinions, which were applied to guide production practice.
Founder of China Aerospace Titanium Alloy Research Institute.
1949 received a doctor's degree in engineering, and was invited by the School of Engineering, new york University, USA, to set up a titanium alloy laboratory. With Qian Dinghua's assistance, a small vacuum non-consumable electric arc furnace for melting button ingots was built, and the balance diagram of titanium, carbon, titanium and nitrogen and the processing texture of titanium alloy were studied according to the entrustment of the US Department of Defense. In his research report, he first proposed the lattice orientation results of tensile, compressive and rolling textures of titanium alloys. At that time, the international research work in this field had not been carried out, and Yan's pioneering research results were cited by some authoritative works on titanium alloys.
1956 aviation industry bureau of the second engine department established aviation materials research institute. Considering that titanium alloy is a new important aviation material, it is listed as the key specialty of the institute. A group of young technicians, led by Yan, designed and manufactured their own equipment, established non-consumable electrode vacuum arc furnace and 7.5 kg consumable electrode vacuum arc furnace, and successfully produced the first titanium alloy ingot weighing 3 kg in China. At the same time, the first batch of titanium alloy researchers with high technical quality in China have been trained in practice and become the backbone of titanium alloy research in the institute. Yan is a pioneer in titanium alloy research in China.
Founder of China Aviation Superalloy Applied Basic Research.
1962, in order to strengthen the research of applied basic theory, Yan was appointed as the director of the metal physics research room, guiding and participating in some applied basic research of superalloys. Together with Chen, he published a review on "Strengthening of Nickel-based Alloys" in Metal Magazine. According to the atomic radius difference, crystal structure and electron shell structure of nickel and other elements, he analyzed the existing state and strengthening order of various alloying elements in nickel-based alloys, commented on the strengthening mechanism of superalloys, and promoted the ongoing research work of superalloys in China.
Under strict guidance, Aeronautical Materials Institute has successively completed the failure analysis, life determination and life extension of materials such as flame tube sheet delamination, engine blade crack and life extension, compressor disc fracture, J-6 aircraft landing gear repair and afterburner nozzle fracture in production and use. And draw accurate scientific conclusions one by one, and put forward corresponding measures, which have accumulated experience for failure analysis and life extension of aircraft and engine parts. Therefore, the Failure Analysis Committee of China Mechanical Society awarded him the honorary title of excellent worker and a gold medal.
In the process of the transformation of aviation industry from imitation to independent design, in order to solve the problem that aviation materials are designed for new models and serve the original models to prolong their life, Yan Zao proposed in 1978 that two "three combinations" should be implemented, that is, the combination of "design, material and use" and "material, technology and test". Then, according to the positive and negative experience in aviation material research and development for many years, the dialectical relationship among design, material, technology, test and use is summarized, that is, design is dominant, material is foundation, technology is means, test is guarantee and use is inspection. He was also invited to give a report on the application research of materials at the meeting of new materials held by the State Science and Technology Commission.
Founder of fatigue and fracture research of aviation metal materials in China.
Since 1970s, due to the development and application of fracture mechanics and new detection technology, the design of aviation product structure and components has developed from traditional strength design and fatigue design to fracture design and damage tolerance design. In order to meet the needs of new aircraft design, two teams, solid mechanics and material physics, were strictly organized and led, and applied basic research and applied research on fatigue and fracture of metal materials were carried out by combining macro-mechanics and micro-analysis, and some important research results were obtained. Among them, he first summarized the physical model of the first and second stage crack growth into the mechanism of double slip, crack tip passivation and regenerative nucleation, obtained the general expression of fatigue crack growth, expounded the influence law of microstructure, stress ratio, surface state, environmental medium and other factors, and wrote the article "Microscopic Mechanism of Metal Fatigue Fracture".
Yan is the first batch of doctoral supervisors approved by the State Council, and a member of metallurgical evaluation group of the first and second academic degree committees. Participated in many international academic conferences and served as an international member or executive member of 10 academic conferences. From 65438 to 0987, he presided over the 5th International Conference on Mechanical Behavior of Materials (ICM) and was elected as the chairman of the Council. 1988 was elected as the executive member of the Far East Fracture Mechanics Group (FEFG) and the member of the Liaison Committee of the International Conference on Fracture Mechanics (ICF).
199 1 To commemorate the 40th anniversary of China's aviation industry, the Ministry of Aviation Industry awarded Yan the aviation gold medal, the highest honor of the Ministry, in recognition of his outstanding contribution to China's aerospace industry. Yan edited, translated and published monographs and translations such as Aviation Materials Science, Strengthening of Nickel-based Superalloys, Fatigue and Fracture of Metals, and Handbook of Fatigue Crack Growth Rate and Plastic Deformation and Fracture of Materials, and published more than 200 academic papers. He also served as the deputy editor-in-chief of the series of Materials Science and Testing Technology, presided over the compilation of professional books such as China Aeronautical Materials Manual (1st and 2nd editions), Proceedings of the 5th International Conference on Mechanical Behavior of Materials and various manuals on mechanical properties, which provided valuable data and information for production, scientific research and teaching, and made outstanding achievements in disseminating new technologies and materials. The basic situation is as follows:
Chinese
1, Yan Study on texture of metal working. Journal of Beijing University of Technology,1956,2 (1):1-15.
2. Yan Gaoming. Determination of metal structure by x-ray diffraction. Proceedings of the first national conference on progress of X-ray and electron microscopy. (Shanghai),1963:163-199.
3. Yan and Chen. Strengthening of Nickel-based Alloys, Journal of Metallurgy,1964,7 (3): 307-321.
4. The effect of texture of Yan, Yuan and pure copper on the internal friction peak of grain boundary. Journal of Physics,1975,24 (1): 51~ 62.
5. Yan Gaoming. Fatigue crack growth process of metals and its microscopic mechanism. Proceedings of the First Conference on Fracture Mechanics and Fracture Physics (Wuhan), 1978: 179-223.
6. Yan Gaoming. Characteristics of initial fatigue crack growth and its influencing factors. Journal of Aviation,1983,4 (2):13-29.
7. Yan and Liu Caimu (translated). Fatigue and fracture of metals. Shanghai: Science and Technology Press, 1983.
8. Yan Gaoming. Aviation materials science. Shanghai: Science and Technology Press, 1985.
9. Editor-in-Chief Yan. Handbook of fatigue crack propagation in aviation metal materials. Beijing: Scientific and Technological Information of Institute of Aeronautical Materials, 1985.
10, Yan. Fatigue crack propagation mechanism of structural materials and its engineering application. Journal of Aviation,1985,6 (3): 208-222.
1 1, Yan, Wang Jinyou, Ma. Application of titanium alloy in aviation industry. Proceedings of the 6th National Titanium Alloy Conference, 1987.
12, edited by Yan. China Aviation Materials Manual. Beijing: China Standards Publishing House, 1988.
foreign language
1, Yan Study on texture and earing behavior of cold-rolled (87-89%) and annealed copper strips
2. Yan, W.R. Hibbard Jr. Transverse bending of aluminum single crystal. China Metallurgical Industry Press, 2002.,1949,185: 710-720.
3. Yan. Micro-bending mechanism of plastic deformation. Trans. Amy. , 1949, 185: 1003- 1004
4. Yan and Chongguang Wang. Some microscopic characteristics and mechanisms of metal fatigue behavior. The first sino-us bilateral metal conference. Sugar paste (Beijing), 198 1:345-384
5, Yan, Gu Mingda. Study on crack propagation delay behavior and fatigue life prediction in structural materials, proceedings. ICF intern. Symptoms. Fractal. Mecha warrior. (Beijing), 1983:769-777
6. Yan, Yu Zhonghua, explanation on prediction of fatigue crack growth △ K. RES Mechanica， 1984， 10: 153- 159
7. Yan, Zhang Souhua and Zheng Zemin. Proceedings of the 5th International Conference on Mechanical Behavior of Materials. Pegamon Press (Oxford), 1987
8. Yan, Qu Youjie and Zhang Shouqing. Microscopic study on FCP and fracture characteristics in crack tip region of engineering alloy. Go on. Far East. Group seminar. (Tokyo),1988:167-176
9, Yan, Zhang Shijie, and fatigue crack propagation behavior under spectral load. Go on. CMRS intern. 90, symptoms. J. (Beijing), 1990 Yan, as one of the first batch of doctoral tutors in China, has trained more than 40 doctoral and master students and more than 0 postdoctoral students 10, and has trained a number of graduate tutors for the country.