A remote open-path laser-induced breakdown spectroscopy(LIBS) system was designed and studied in the present work for the purpose of combining the LIBS technique with the steel production line. In this system, the rel...A remote open-path laser-induced breakdown spectroscopy(LIBS) system was designed and studied in the present work for the purpose of combining the LIBS technique with the steel production line. In this system, the relatively simple configuration and optics were employed to measure the steel samples at a remote distance and a hot sample temperature. The system has obtained a robustness for the deviation of the sample position because of the open-path and alloptical structure. The measurement was carried out at different sample temperatures by placing the samples in a muffle furnace with a window in the front door. The results show that the intensity of the spectral lines increased as the sample temperature increased. The influence of the sample temperature on the quantitative analysis of manganese in the steel samples was investigated by measuring ten standard steel samples at different temperatures. Three samples were selected as the test sample for the simulation measurement. The results show that, at the sample temperature of 500 ℃, the average relative error of prediction is 3.1% and the average relative standard deviation is 7.7%, respectively.展开更多
Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness...Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness ofγ-TiAl is still a critical obstacle to its large-scale applications.In this context,researchers have made many attempts to study the machinability ofγ-TiAl.At present,existing relevant reviews have mostly discussed the processing methods ofγ-TiAl.Hence,there is still a lack of a perspective on material properties to analyze the cutting mechanism.Herein,this paper provides the systematic review of such perspectives.Above all,the developmental process,phase transformation,and microstructural evolution ofγ-TiAl are discussed,as well as its deformation mechanism at quasi-static.These topics can provide a materials science foundation for the machining ofγ-TiAl.And then,the review focuses on the cutting mechanism and surface integrity ofγ-TiAl.Moreover,special attention is paid to the microscope deformation mechanism and surface defects evolution ofγ-TiAl during cutting.Finally,the review indicates that the highperformance machining technology ofγ-TiAl faces challenges and proposes potential future research directions.Solving the difficulties during machiningγ-TiAl aero-engine components will accelerate the development of new aero-engines.展开更多
Lubrication and friction conditions vary with deformation during metal forming processes.Significant macro-variations can be observed when a threshold of deformation is reached.This study shows that during the cold co...Lubrication and friction conditions vary with deformation during metal forming processes.Significant macro-variations can be observed when a threshold of deformation is reached.This study shows that during the cold compression processing of#45(AISI 1045)steel rings,the magnitude of friction and surface roughness(Ra)changes significantly upon reaching a 45%reduction in ring height.For example,the Ra of compressed ring specimens increased by approximately 55%immediately before and after reaching this threshold,compared to an 18% or 25%variation over a 35%-45%or a 45%-55%reduction in height,respectively.The ring compression test conducted by this study indicates that the Coulomb friction coefficient and Tresca friction factor mare 0.105 and 0.22,respectively,when the reduction in height is less than 45%;and 0.11 and 0.24,respectively,when the reduction in height is greater than 45%.展开更多
基金supported by National Natural Science Foundation of China (Nos. 51506171 and 51675415)National Natural Science Foundation of China for Key Program (No. 51335009)+1 种基金National Key Research and Development Program of China (No. 2017YFD0700200)the joint research fund between Tokushima University and Xi’an Jiaotong University
文摘A remote open-path laser-induced breakdown spectroscopy(LIBS) system was designed and studied in the present work for the purpose of combining the LIBS technique with the steel production line. In this system, the relatively simple configuration and optics were employed to measure the steel samples at a remote distance and a hot sample temperature. The system has obtained a robustness for the deviation of the sample position because of the open-path and alloptical structure. The measurement was carried out at different sample temperatures by placing the samples in a muffle furnace with a window in the front door. The results show that the intensity of the spectral lines increased as the sample temperature increased. The influence of the sample temperature on the quantitative analysis of manganese in the steel samples was investigated by measuring ten standard steel samples at different temperatures. Three samples were selected as the test sample for the simulation measurement. The results show that, at the sample temperature of 500 ℃, the average relative error of prediction is 3.1% and the average relative standard deviation is 7.7%, respectively.
基金co-supported by the Science Center for Gas Turbine Project,China(No.P2022-A-IV-001-002)the National Natural Science Foundation of China(Nos.51875473 and 91960203).
文摘Owing to its outstanding mechanical properties,γ-TiAl is desirable materials for crossgeneration aero-engines.Nearly 70 years of exploration have made it into the initial application.However,the intrinsic brittleness ofγ-TiAl is still a critical obstacle to its large-scale applications.In this context,researchers have made many attempts to study the machinability ofγ-TiAl.At present,existing relevant reviews have mostly discussed the processing methods ofγ-TiAl.Hence,there is still a lack of a perspective on material properties to analyze the cutting mechanism.Herein,this paper provides the systematic review of such perspectives.Above all,the developmental process,phase transformation,and microstructural evolution ofγ-TiAl are discussed,as well as its deformation mechanism at quasi-static.These topics can provide a materials science foundation for the machining ofγ-TiAl.And then,the review focuses on the cutting mechanism and surface integrity ofγ-TiAl.Moreover,special attention is paid to the microscope deformation mechanism and surface defects evolution ofγ-TiAl during cutting.Finally,the review indicates that the highperformance machining technology ofγ-TiAl faces challenges and proposes potential future research directions.Solving the difficulties during machiningγ-TiAl aero-engine components will accelerate the development of new aero-engines.
基金National Natural Science Foundation of China(Grant Nos.51675415 and 51335009)the Open Research Fund of the Key Laboratory of High-Performance Complex Manufacturing,Central South University(Kfkt2016-06).
文摘Lubrication and friction conditions vary with deformation during metal forming processes.Significant macro-variations can be observed when a threshold of deformation is reached.This study shows that during the cold compression processing of#45(AISI 1045)steel rings,the magnitude of friction and surface roughness(Ra)changes significantly upon reaching a 45%reduction in ring height.For example,the Ra of compressed ring specimens increased by approximately 55%immediately before and after reaching this threshold,compared to an 18% or 25%variation over a 35%-45%or a 45%-55%reduction in height,respectively.The ring compression test conducted by this study indicates that the Coulomb friction coefficient and Tresca friction factor mare 0.105 and 0.22,respectively,when the reduction in height is less than 45%;and 0.11 and 0.24,respectively,when the reduction in height is greater than 45%.