To investigate the effect of alternating magnetic field on austenite transformation process in the case of rapid heating,the austenite kinetics model of AISI 1045 steel was built for spot continual induction hardening...To investigate the effect of alternating magnetic field on austenite transformation process in the case of rapid heating,the austenite kinetics model of AISI 1045 steel was built for spot continual induction hardening(SCIH)process.The results shows that the effect of alternating magnetic field on austenite transformation fraction reaches the maximum(about 3%)when heating rate is the lowest.Relatively low magnetic flux density still has a certain effect on the austenite transformation process during the SCIH process.Concave surface structure can reduce the influence scope of alternating magnetic field on surface in all cases and the minimum influence scope appears when the feed path of inductor is longitudinal.Convex surface structure can minimize the influence scope of alternating magnetic field in depth when the feed path of inductor is longitudinal.The austenite distribution of transitional region on surface for horizontal movement is more uniform than that for longitudinal movement.The austenite distribution of transitional region in depth for longitudinal movement is more uniform than that for horizontal movement.The simulated results are consistent with the experimental results and the austenite transformation kinetics model developed for SCIH process is valid.展开更多
In order to investigate and predict the material properties of curved surface AISI 1045 steel component during spot continual induction hardening(SCIH),a 3D model for curved surface workpieces which coupled electromag...In order to investigate and predict the material properties of curved surface AISI 1045 steel component during spot continual induction hardening(SCIH),a 3D model for curved surface workpieces which coupled electromagnetic,temperature and phase transformation fields was built by finite element software ANSYS.A small size inductor and magnetizer were used in this model,which can move along the top surface of workpiece flexibly.The effect of inductor moving velocity and workpiece radius on temperature field was analyzed and the heating delay phenomenon was found through comparing the simulated results.The temperature field results indicate that the heating delay phenomenon is more obvious under high inductor moving velocity condition.This trend becomes more obvious if the workpiece radius becomes larger.The predictions of microstructure and micro-hardness distribution were also carried out via this model.The predicted results show that the inductor moving velocity is the dominated factor for the distribution of 100% martensite region and phase transformation region.The influencing factor of workpiece radius on 100% martensite region and phase transformation region distribution is obvious under relatively high inductor moving velocity but inconspicuous under relatively low inductor moving velocity.展开更多
This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different...This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different statistical methods.Vegetable oil was preferred as cutting fluid,and Taguchi method was used in the preparation of the test pattern.After testing with the prepared test pattern,cutting performance in all parameters has been improved according to dry conditions thanks to the MQL system.The highest tool life was obtained by using cutting parameters of 7.5 m cutting length,100 m/min cutting speed,100 mL/h MQL flow rate and 0.1 mm/tooth feed rate.Optimum cutting parameters were determined according to the Taguchi analysis,and the obtained parameters were confirmed with the verification tests.In addition,the optimum test parameter was determined by applying the gray relational analysis method.After using ANOVA analysis according to the measured surface roughness and cutting force values,the most effective cutting parameter was observed to be the feed rate.In addition,the models for surface roughness and cutting force values were obtained with precisions of 99.63%and 99.68%,respectively.Effective wear mechanisms were found to be abrasion and adhesion.展开更多
基金Projects(51905390,51575415)supported by the National Natural Science Foundation of China。
文摘To investigate the effect of alternating magnetic field on austenite transformation process in the case of rapid heating,the austenite kinetics model of AISI 1045 steel was built for spot continual induction hardening(SCIH)process.The results shows that the effect of alternating magnetic field on austenite transformation fraction reaches the maximum(about 3%)when heating rate is the lowest.Relatively low magnetic flux density still has a certain effect on the austenite transformation process during the SCIH process.Concave surface structure can reduce the influence scope of alternating magnetic field on surface in all cases and the minimum influence scope appears when the feed path of inductor is longitudinal.Convex surface structure can minimize the influence scope of alternating magnetic field in depth when the feed path of inductor is longitudinal.The austenite distribution of transitional region on surface for horizontal movement is more uniform than that for longitudinal movement.The austenite distribution of transitional region in depth for longitudinal movement is more uniform than that for horizontal movement.The simulated results are consistent with the experimental results and the austenite transformation kinetics model developed for SCIH process is valid.
基金Project (51175392) supported by the National Natural Science Foundation of ChinaProject (2014BAA012) supported by the Key Project of Hubei Province Science & Technology Pillar Program,ChinaProjects (2012-IV-067,2013-VII-020) supported by the Fundamental Research Funds for the Central Universities of China
文摘In order to investigate and predict the material properties of curved surface AISI 1045 steel component during spot continual induction hardening(SCIH),a 3D model for curved surface workpieces which coupled electromagnetic,temperature and phase transformation fields was built by finite element software ANSYS.A small size inductor and magnetizer were used in this model,which can move along the top surface of workpiece flexibly.The effect of inductor moving velocity and workpiece radius on temperature field was analyzed and the heating delay phenomenon was found through comparing the simulated results.The temperature field results indicate that the heating delay phenomenon is more obvious under high inductor moving velocity condition.This trend becomes more obvious if the workpiece radius becomes larger.The predictions of microstructure and micro-hardness distribution were also carried out via this model.The predicted results show that the inductor moving velocity is the dominated factor for the distribution of 100% martensite region and phase transformation region.The influencing factor of workpiece radius on 100% martensite region and phase transformation region distribution is obvious under relatively high inductor moving velocity but inconspicuous under relatively low inductor moving velocity.
文摘This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different statistical methods.Vegetable oil was preferred as cutting fluid,and Taguchi method was used in the preparation of the test pattern.After testing with the prepared test pattern,cutting performance in all parameters has been improved according to dry conditions thanks to the MQL system.The highest tool life was obtained by using cutting parameters of 7.5 m cutting length,100 m/min cutting speed,100 mL/h MQL flow rate and 0.1 mm/tooth feed rate.Optimum cutting parameters were determined according to the Taguchi analysis,and the obtained parameters were confirmed with the verification tests.In addition,the optimum test parameter was determined by applying the gray relational analysis method.After using ANOVA analysis according to the measured surface roughness and cutting force values,the most effective cutting parameter was observed to be the feed rate.In addition,the models for surface roughness and cutting force values were obtained with precisions of 99.63%and 99.68%,respectively.Effective wear mechanisms were found to be abrasion and adhesion.
