Surface characteristics play a very important role in medical implants and among surface features, surface roughness is very effective in some medical applications. Among the various methods used to improve surface roughness, magnetic abrasive finishing (MAF) process has been widely used in medical engineering. In this study, the effect of abrasive particle morphology along with four other process parameters, including type of work metal, finishing time, speed of finishing operation, and the type of abrasive powder were experimentally evaluated. Full factorial technique was used for design of experiment. Three commonly used metals in orthopedic implants i.e., Ti-6Al-4V alloy, AZ31 alloy and austenitic stainless-steel 316LVM, were selected for this study. Also, two types of magnetic abrasive particles with different shapes (spherical and rod-shaped) were considered in the experiments. The results of the experiments indicated that the morphology of the abrasive particles and the finishing time had the greatest effect on surface roughness and using rod-shaped abrasive particles resulted in better surface quality comparing to the spherical particles. Besides, the surface quality of steel 316LVM after MAF was the best among the other examined metals. Interaction plots of ANOVA also showed that interactions of material with morphology of abrasive particles, and material with machining time were found to be reasonably significant.
{"title":"Effect of abrasive particle morphology along with other influencing parameters in magnetic abrasive finishing process","authors":"F. Ahmadi, Hassan Beiramlou, P. Yazdi","doi":"10.1051/MECA/2021013","DOIUrl":"https://doi.org/10.1051/MECA/2021013","url":null,"abstract":"Surface characteristics play a very important role in medical implants and among surface features, surface roughness is very effective in some medical applications. Among the various methods used to improve surface roughness, magnetic abrasive finishing (MAF) process has been widely used in medical engineering. In this study, the effect of abrasive particle morphology along with four other process parameters, including type of work metal, finishing time, speed of finishing operation, and the type of abrasive powder were experimentally evaluated. Full factorial technique was used for design of experiment. Three commonly used metals in orthopedic implants i.e., Ti-6Al-4V alloy, AZ31 alloy and austenitic stainless-steel 316LVM, were selected for this study. Also, two types of magnetic abrasive particles with different shapes (spherical and rod-shaped) were considered in the experiments. The results of the experiments indicated that the morphology of the abrasive particles and the finishing time had the greatest effect on surface roughness and using rod-shaped abrasive particles resulted in better surface quality comparing to the spherical particles. Besides, the surface quality of steel 316LVM after MAF was the best among the other examined metals. Interaction plots of ANOVA also showed that interactions of material with morphology of abrasive particles, and material with machining time were found to be reasonably significant.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"58 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84204147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, local-thickened plates are adopted for aluminum alloy square cups stamping with relatively low values of residual stresses and small radius at the bottom corner. By utilizing numerical and experimental methods, the effects of process parameters and plate local thickening on the residual stress distribution of hot stamped aluminum alloy square cups are studied. Furthermore, the influence of plate local thickening on the radius of bottom corner of square cups is also investigated. The results showed that with an increase in the forming temperature, blank holder force and die corner radius, residual stresses in hot stamped square cups can be reduced. The same effect can be achieved by decreasing the die entrance radius. As opposed to the flat plates, using local-thickened plates can not only reduce the residual stresses values in hot stamped square cups, but also decrease the radius at the bottom corner of square cups. When the optimized thickening scheme of plate is used, the smaller radius at the bottom corner, the lower residual stresses in the square cups are obtained.
{"title":"Investigation of process parameters and plate local thickening on residual stresses in hot stamping process","authors":"Jinbo Li, Xiao-hui Chen, Xianlong Liu","doi":"10.1051/MECA/2021015","DOIUrl":"https://doi.org/10.1051/MECA/2021015","url":null,"abstract":"In this paper, local-thickened plates are adopted for aluminum alloy square cups stamping with relatively low values of residual stresses and small radius at the bottom corner. By utilizing numerical and experimental methods, the effects of process parameters and plate local thickening on the residual stress distribution of hot stamped aluminum alloy square cups are studied. Furthermore, the influence of plate local thickening on the radius of bottom corner of square cups is also investigated. The results showed that with an increase in the forming temperature, blank holder force and die corner radius, residual stresses in hot stamped square cups can be reduced. The same effect can be achieved by decreasing the die entrance radius. As opposed to the flat plates, using local-thickened plates can not only reduce the residual stresses values in hot stamped square cups, but also decrease the radius at the bottom corner of square cups. When the optimized thickening scheme of plate is used, the smaller radius at the bottom corner, the lower residual stresses in the square cups are obtained.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"52 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87137973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The flexible bearing is a key component of harmonic reducer enabling the flexspline to generate a controllable elastic deformation. Its performance and life will significantly affect the normal operation of harmonic reducer. In order to improve the life and the working performance of the flexible bearing, the calculation of its load distribution is necessary. Based on the theory of thin-walled ring, the relationship between radial deformation and load of three-force ring was derived. Then a superposition model of three-force ring was developed to calculate rapidly the load distribution of flexible bearings with elliptical cams in harmonic reducers. The validity of the proposed model was proved by comparing with a static analysis model. In this paper, the influences of ball number and external load on the load distribution, radial deformation and bending normal stress of outer ring were investigated by three-force ring superposition method. Based on the deformation of three-force ring, the deformation characteristics and bending normal stress distribution of outer ring of the flexible bearing were analyzed, and several regular results were found.
{"title":"Load analysis and deformation research of the flexible bearing based on a three-force ring superposition method","authors":"Yang Yu, E. Zhu, Xiaoyang Chen, Yang Wang","doi":"10.1051/MECA/2021030","DOIUrl":"https://doi.org/10.1051/MECA/2021030","url":null,"abstract":"The flexible bearing is a key component of harmonic reducer enabling the flexspline to generate a controllable elastic deformation. Its performance and life will significantly affect the normal operation of harmonic reducer. In order to improve the life and the working performance of the flexible bearing, the calculation of its load distribution is necessary. Based on the theory of thin-walled ring, the relationship between radial deformation and load of three-force ring was derived. Then a superposition model of three-force ring was developed to calculate rapidly the load distribution of flexible bearings with elliptical cams in harmonic reducers. The validity of the proposed model was proved by comparing with a static analysis model. In this paper, the influences of ball number and external load on the load distribution, radial deformation and bending normal stress of outer ring were investigated by three-force ring superposition method. Based on the deformation of three-force ring, the deformation characteristics and bending normal stress distribution of outer ring of the flexible bearing were analyzed, and several regular results were found.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"96 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91355380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fanming Meng, Sheng Yang, Zhi-tao Cheng, Yong Zheng, Bin Wang
A non-Newtonian thermal elastohydrodynamic lubrication (TEHL) model for the elliptic contact is established, into which the inertia forces of the lubricant is incorporated. In doing so, the film pressure and film temperature are solved using the associated equations. Meanwhile, the elastic deformation is calculated with the discrete convolution and fast Fourier transform (DC-FFT) method. A film thickness experiment is conducted to validate the TEHL model considering the inertia forces. Further, effects of the inertia forces on the TEHL performances are studied at different operation conditions. The results show that when the inertia forces are considered, the central and minimum film thicknesses increase and film temperature near the inlet increases obviously. Moreover, the inertial solution of the central film thickness is closer to the experimental result compared with its inertialess value.
{"title":"Effect of fluid inertia force on thermal elastohydrodynamic lubrication of elliptic contact","authors":"Fanming Meng, Sheng Yang, Zhi-tao Cheng, Yong Zheng, Bin Wang","doi":"10.1051/MECA/2021010","DOIUrl":"https://doi.org/10.1051/MECA/2021010","url":null,"abstract":"A non-Newtonian thermal elastohydrodynamic lubrication (TEHL) model for the elliptic contact is established, into which the inertia forces of the lubricant is incorporated. In doing so, the film pressure and film temperature are solved using the associated equations. Meanwhile, the elastic deformation is calculated with the discrete convolution and fast Fourier transform (DC-FFT) method. A film thickness experiment is conducted to validate the TEHL model considering the inertia forces. Further, effects of the inertia forces on the TEHL performances are studied at different operation conditions. The results show that when the inertia forces are considered, the central and minimum film thicknesses increase and film temperature near the inlet increases obviously. Moreover, the inertial solution of the central film thickness is closer to the experimental result compared with its inertialess value.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"21 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90149531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The accuracy of nucleic acid extraction and diagnosis depends on the sealing performance of the pipetting device. The rubber seal ring at the front end of the pipette shaft is a critical component for ensuring the sealing performance of the pipetting device. In this study, an accurate prediction and analysis were made on the fatigue life of the pipette shaft seal ring. ABAQUS was used to simulate the assembly process of pipette shaft seal ring and disposable tip, and the dangerous cross-section segments on the seal rings were preliminarily identified according to a stress nephogram. Based on the continuum damage mechanics theory, the fatigue life prediction model was built where the effective strain was taken as a damage parameter, and the fatigue life of the dangerous cross-section of the pipette shaft seal ring was calculated. By observing failed seal rings in actual use, it was found that the worn positions of the failed seal rings were the same as the sites of the shortest-lived node segments, thus verifying the accuracy of fatigue life prediction model and fatigue life analysis.
{"title":"Effective strain range-based prediction and analysis of the fatigue life of pipette shaft seal ring","authors":"Chenxue Wang, Q. Su, Zeng Huang, Z. Lian, Yu Liu","doi":"10.1051/meca/2021038","DOIUrl":"https://doi.org/10.1051/meca/2021038","url":null,"abstract":"The accuracy of nucleic acid extraction and diagnosis depends on the sealing performance of the pipetting device. The rubber seal ring at the front end of the pipette shaft is a critical component for ensuring the sealing performance of the pipetting device. In this study, an accurate prediction and analysis were made on the fatigue life of the pipette shaft seal ring. ABAQUS was used to simulate the assembly process of pipette shaft seal ring and disposable tip, and the dangerous cross-section segments on the seal rings were preliminarily identified according to a stress nephogram. Based on the continuum damage mechanics theory, the fatigue life prediction model was built where the effective strain was taken as a damage parameter, and the fatigue life of the dangerous cross-section of the pipette shaft seal ring was calculated. By observing failed seal rings in actual use, it was found that the worn positions of the failed seal rings were the same as the sites of the shortest-lived node segments, thus verifying the accuracy of fatigue life prediction model and fatigue life analysis.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90475141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Da-lian Yang, Zhang Fanyu, J. Miao, Hongxian Zhang, Renjie Li, Tao Jie
Misalignment fault is the main factor that affects the normal running of dual-rotor system. Quantitative identification the misalignment fault is an important way to ensure the safe and stable service of the dual-rotor system, while the identification accuracy of traditional methods is low. Aiming at the above problems, this paper proposed a dual-rotor misalignment fault quantitative identification method based on DBN and D-S evidence theory improved by mutual information measure (MIMD-S). Seven groups experiments were conducted and several vibration signals were collected. By comparing it with the traditional methods D-S, and Pignistic improved D-S (PD-S) evidence theory, the results show that the method proposed in this paper improves the accuracy of the misalignment fault quantitative identification of the dual-rotor, the identification error rate was only 0.36%.
{"title":"Dual-rotor misalignment fault quantitative identification based on DBN and improved D-S evidence theory","authors":"Da-lian Yang, Zhang Fanyu, J. Miao, Hongxian Zhang, Renjie Li, Tao Jie","doi":"10.1051/MECA/2021022","DOIUrl":"https://doi.org/10.1051/MECA/2021022","url":null,"abstract":"Misalignment fault is the main factor that affects the normal running of dual-rotor system. Quantitative identification the misalignment fault is an important way to ensure the safe and stable service of the dual-rotor system, while the identification accuracy of traditional methods is low. Aiming at the above problems, this paper proposed a dual-rotor misalignment fault quantitative identification method based on DBN and D-S evidence theory improved by mutual information measure (MIMD-S). Seven groups experiments were conducted and several vibration signals were collected. By comparing it with the traditional methods D-S, and Pignistic improved D-S (PD-S) evidence theory, the results show that the method proposed in this paper improves the accuracy of the misalignment fault quantitative identification of the dual-rotor, the identification error rate was only 0.36%.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"85 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76319633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qin He, P. Zhang, Shunxin Cao, Ruijun Zhang, Qing Zhang
Aiming at the inconsistency between the vibration of the car and the car frame in the actual operation of a high-speed elevator and the horizontal vibration caused by the roughness excitation of the guide rail, this study designs a gas–liquid active guide shoe and establishes a horizontal vibration model of the 8-DOF high-speed elevator car system separated from the car and the car frame. Then, the correctness of the model is verified by experiments. Based on this, a fuzzy neural network intelligent vibration reduction controller based on the Mamdani model is designed and simulated by MATLAB. The results show that the root mean square value, mean value, and maximum value of vibration acceleration are reduced by more than 55% after using the fuzzy neural network control method, and the suppression effect is better than that of BP neural network control. Therefore, the intelligent vibration absorption controller designed by this research institute can effectively suppress the horizontal vibration of high-speed elevators.
{"title":"Intelligent control of horizontal vibration of high-speed elevator based on gas–liquid active guide shoes","authors":"Qin He, P. Zhang, Shunxin Cao, Ruijun Zhang, Qing Zhang","doi":"10.1051/MECA/2020100","DOIUrl":"https://doi.org/10.1051/MECA/2020100","url":null,"abstract":"Aiming at the inconsistency between the vibration of the car and the car frame in the actual operation of a high-speed elevator and the horizontal vibration caused by the roughness excitation of the guide rail, this study designs a gas–liquid active guide shoe and establishes a horizontal vibration model of the 8-DOF high-speed elevator car system separated from the car and the car frame. Then, the correctness of the model is verified by experiments. Based on this, a fuzzy neural network intelligent vibration reduction controller based on the Mamdani model is designed and simulated by MATLAB. The results show that the root mean square value, mean value, and maximum value of vibration acceleration are reduced by more than 55% after using the fuzzy neural network control method, and the suppression effect is better than that of BP neural network control. Therefore, the intelligent vibration absorption controller designed by this research institute can effectively suppress the horizontal vibration of high-speed elevators.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"15 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78781245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Agathe Reille, V. Champaney, F. Daim, Y. Tourbier, Nicolas Hascoet, D. González, E. Cueto, J. Duval, F. Chinesta
Solving mechanical problems in large structures with rich localized behaviors remains a challenging issue despite the enormous advances in numerical procedures and computational performance. In particular, these localized behaviors need for extremely fine descriptions, and this has an associated impact in the number of degrees of freedom from one side, and the decrease of the time step employed in usual explicit time integrations, whose stability scales with the size of the smallest element involved in the mesh. In the present work we propose a data-driven technique for learning the rich behavior of a local patch and integrate it into a standard coarser description at the structure level. Thus, localized behaviors impact the global structural response without needing an explicit description of that fine scale behaviors.
{"title":"Learning data-driven reduced elastic and inelastic models of spot-welded patches","authors":"Agathe Reille, V. Champaney, F. Daim, Y. Tourbier, Nicolas Hascoet, D. González, E. Cueto, J. Duval, F. Chinesta","doi":"10.1051/MECA/2021031","DOIUrl":"https://doi.org/10.1051/MECA/2021031","url":null,"abstract":"Solving mechanical problems in large structures with rich localized behaviors remains a challenging issue despite the enormous advances in numerical procedures and computational performance. In particular, these localized behaviors need for extremely fine descriptions, and this has an associated impact in the number of degrees of freedom from one side, and the decrease of the time step employed in usual explicit time integrations, whose stability scales with the size of the smallest element involved in the mesh. In the present work we propose a data-driven technique for learning the rich behavior of a local patch and integrate it into a standard coarser description at the structure level. Thus, localized behaviors impact the global structural response without needing an explicit description of that fine scale behaviors.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"318 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76894599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mechanics & Industry publishes all articles in Open Access from January 2021","authors":"R. Dufour, E. Arquis, Ariana Fuga","doi":"10.1051/MECA/2021020","DOIUrl":"https://doi.org/10.1051/MECA/2021020","url":null,"abstract":"","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"63 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74996675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Longlong Geng, Xiaozhong Deng, Hua Zhang, S. Nie, Chuang Jiang
In this paper, a double-side milling method on spiral bevel gear is proposed. First, according to the tooth taper processed by double-side milling method, the influence of dedendum angle on the tooth taper was researched. Taking cut parameters into comprehensive consideration, the geometric parameters were designed through the inclination of root line and modified mean point in which machine setting parameters calculated was selected. Only the modified mean point met the meshing equation, and the error of pressure angle would increase as far away from the modified mean point in tooth line. The error would lead to bias in contact. A helical correction motion was introduced and the influence of helical motion coefficient on tooth surface topology was studied. Based on the meshing performance, a suitable coefficient was calculated. Finally, an example was illustrated. The experimental results were consistent with the theoretical analysis. The validity of the proposed method is verified.
{"title":"Theory and experimental research on spiral bevel gear by double-side milling method","authors":"Longlong Geng, Xiaozhong Deng, Hua Zhang, S. Nie, Chuang Jiang","doi":"10.1051/MECA/2021032","DOIUrl":"https://doi.org/10.1051/MECA/2021032","url":null,"abstract":"In this paper, a double-side milling method on spiral bevel gear is proposed. First, according to the tooth taper processed by double-side milling method, the influence of dedendum angle on the tooth taper was researched. Taking cut parameters into comprehensive consideration, the geometric parameters were designed through the inclination of root line and modified mean point in which machine setting parameters calculated was selected. Only the modified mean point met the meshing equation, and the error of pressure angle would increase as far away from the modified mean point in tooth line. The error would lead to bias in contact. A helical correction motion was introduced and the influence of helical motion coefficient on tooth surface topology was studied. Based on the meshing performance, a suitable coefficient was calculated. Finally, an example was illustrated. The experimental results were consistent with the theoretical analysis. The validity of the proposed method is verified.","PeriodicalId":49018,"journal":{"name":"Mechanics & Industry","volume":"58 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84132226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}