Friction and wear phenomenon is a complex nonlinear system,and it is also a significant problem in the process of metal cutting.In order to systematically analyze the friction and wear process of tool material-workpie...Friction and wear phenomenon is a complex nonlinear system,and it is also a significant problem in the process of metal cutting.In order to systematically analyze the friction and wear process of tool material-workpiece material friction pair in the cutting process of high hardness alloy steel under different lubrication conditions,the chaotic characteristics of friction process between high hardness alloy steel and cemented carbide under the lubrication C60 nano-particles fluid are studied based on the chaos theory.Firstly,the friction and wear experiments of the friction pair between high hardness alloy steel and cemented carbide tool are carried out based on the ring-block friction and wear tester,and the results of friction force signal in time domain and wear width are obtained.Then,the friction signals in time domain are processed and transformed based on phase space reconstruction and recurrence plot theory,and the recurrence plots of different experimental groups under different lubrication conditions are generated.The evolution law of recurrence plot is further observed and studied,and the recursive quantitative index is analyzed.Finally,the cutting experiments of tool wear are carried out.The results show that the proposed method can intuitively and accurately reveal the wear evolution process and the wear feature identification law of the tool material-high hardness alloy steel pair under different lubrication conditions.Meanwhile,it is found that when the concentration of C60 nanoparticles is 200∼300 ppm,the stability of the friction pair system is best.The proposed method can provide a strategy for wear prediction in cutting process,and provide a theoretical basis and technical support for antifriction lubrication methods in practical cutting applications.展开更多
Iron oxide（Fe2O3） was doped onto fullerene[60]（C（60）） to form a C（60）‐Fe2O3 composite using an easy and scalable impregnation method. The as‐prepared C（60）‐Fe2O3 samples were characterized by powder X‐ra...Iron oxide（Fe2O3） was doped onto fullerene[60]（C（60）） to form a C（60）‐Fe2O3 composite using an easy and scalable impregnation method. The as‐prepared C（60）‐Fe2O3 samples were characterized by powder X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electron microscopy, high‐resolution transmission electron microscopy, UV‐vis absorption spectroscopy, Raman spec‐troscopy, and Fourier transform infrared spectroscopy. The photocatalytic activity of the C（60）‐Fe2O3 catalyst was evaluated by examining the degradation of methylene blue（MB）, rhodamine B（RhB）, methyl orange（MO）, and phenol under visible light（λ 420 nm） in the presence of hydrogen per‐oxide. The results showed that the catalyst exhibited excellent catalytic properties over a wide pH range 3.06–10.34. Under optimal conditions, 98.9% discoloration and 71% mineralization of MB were achieved in 80 min. Leaching test results indicated that the leaching of iron from the catalyst was negligible and that the catalyst had a high photocatalytic activity after five reaction cycles. The catalyst was also efficient in the degradation of RhB, MO, and phenol. These findings could be at‐tributed to the synergetic effects of C（60） and Fe2O3. We used active species trapping experiments to determine the main active oxidant in the photocatalytic reaction process and found that hydroxyl radicals played a major role in the entire process.展开更多
基金The work is financially supported by National Natural Science Foundation of China(No.51605403)National Key Research and Development Project(2020YFB1713503)+3 种基金Natural Science Foundation of Guangdong Province,China(No.2015A030310010)Natural Science Foundation of Fujian Province,China(No.2016J01012)the Aero-nautical Science Foundation of China(No.20183368004)the Fundamental Research Funds for the Central Universities under Grant(No.20720190009).
文摘Friction and wear phenomenon is a complex nonlinear system,and it is also a significant problem in the process of metal cutting.In order to systematically analyze the friction and wear process of tool material-workpiece material friction pair in the cutting process of high hardness alloy steel under different lubrication conditions,the chaotic characteristics of friction process between high hardness alloy steel and cemented carbide under the lubrication C60 nano-particles fluid are studied based on the chaos theory.Firstly,the friction and wear experiments of the friction pair between high hardness alloy steel and cemented carbide tool are carried out based on the ring-block friction and wear tester,and the results of friction force signal in time domain and wear width are obtained.Then,the friction signals in time domain are processed and transformed based on phase space reconstruction and recurrence plot theory,and the recurrence plots of different experimental groups under different lubrication conditions are generated.The evolution law of recurrence plot is further observed and studied,and the recursive quantitative index is analyzed.Finally,the cutting experiments of tool wear are carried out.The results show that the proposed method can intuitively and accurately reveal the wear evolution process and the wear feature identification law of the tool material-high hardness alloy steel pair under different lubrication conditions.Meanwhile,it is found that when the concentration of C60 nanoparticles is 200∼300 ppm,the stability of the friction pair system is best.The proposed method can provide a strategy for wear prediction in cutting process,and provide a theoretical basis and technical support for antifriction lubrication methods in practical cutting applications.
基金supported by the National Natural Science Foundation of China (21347006, 21576175, 51478285, 51403148)the Opening Project of Key Laboratory of Jiangsu Province environmental science and engineering of Suzhou University of Science and Technology (zd131205)Collabora‐tive Innovation Center of Technology and Material of Water Treatment and Suzhou Key Lab of Separation and Purification Materials & Technologies (SZS201512)~~
文摘Iron oxide（Fe2O3） was doped onto fullerene[60]（C（60）） to form a C（60）‐Fe2O3 composite using an easy and scalable impregnation method. The as‐prepared C（60）‐Fe2O3 samples were characterized by powder X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electron microscopy, high‐resolution transmission electron microscopy, UV‐vis absorption spectroscopy, Raman spec‐troscopy, and Fourier transform infrared spectroscopy. The photocatalytic activity of the C（60）‐Fe2O3 catalyst was evaluated by examining the degradation of methylene blue（MB）, rhodamine B（RhB）, methyl orange（MO）, and phenol under visible light（λ 420 nm） in the presence of hydrogen per‐oxide. The results showed that the catalyst exhibited excellent catalytic properties over a wide pH range 3.06–10.34. Under optimal conditions, 98.9% discoloration and 71% mineralization of MB were achieved in 80 min. Leaching test results indicated that the leaching of iron from the catalyst was negligible and that the catalyst had a high photocatalytic activity after five reaction cycles. The catalyst was also efficient in the degradation of RhB, MO, and phenol. These findings could be at‐tributed to the synergetic effects of C（60） and Fe2O3. We used active species trapping experiments to determine the main active oxidant in the photocatalytic reaction process and found that hydroxyl radicals played a major role in the entire process.
