Mechanical and structural properties of ternary system of TiN-TiO-TiC are investigated using first principle methods. 70 different compositions of Ti100(NOC)100 with cubic structure are examined in order to illustrate...Mechanical and structural properties of ternary system of TiN-TiO-TiC are investigated using first principle methods. 70 different compositions of Ti100(NOC)100 with cubic structure are examined in order to illustrate the trend of properties variations. The geometry of compounds is optimized, and then, their chemical stability is assessed. Afterward,shear, bulk and young moduli, Cauchy pressure, Zener ratio, hardness and H3/E2 ratio are computed based on elastic constants. Graphical ternary diagram is used to represent the trend of such properties when the content of nitrogen,oxygen and carbon varies. The results show that incorporation of oxygen into the system decreases the hardness and H^3/E^2 ratio while subsequently ductility increases due to positive Cauchy pressure. It is revealed that the maximum H^3/E^2 ratio occurs when both nitrogen and carbon with a little amount of oxygen are incorporated. Ti_(100) N_(30) C_(70) owns the highest hardness and H^3/E^2 ratio equal to 39.5 and 0.2 GPa, respectively. In addition, the G/B of this compound,which is about 0.9, shows it is brittle. It is also observed that the solid solutions have better mechanical properties with respect to titanium nitride and titanium carbide. The obtained results could be used to enhance monolayer coatings as well as to design multilayers with specific mechanical properties.展开更多
This study presents spatio-temporal development of the ionisation waves(IWs)along one dielectric tube with an extra alternating electric field.A pulsed direct current power supply is used for generating the IWs,and an...This study presents spatio-temporal development of the ionisation waves(IWs)along one dielectric tube with an extra alternating electric field.A pulsed direct current power supply is used for generating the IWs,and another alternating current power supply is used for altering the distribution of electric fields along the dielectric tube.The measurements show that the propagation velocity and density of IWs are strongly affected by the external electric field.The direct relation between external electric field and the velocity of the IWs is demonstrated.Further analysis indicates that the external electric field can be utilised to control the propagation of the IWs,resulting in a change of their density and velocity.展开更多
基金the financial support of University of Tehran Science and Technology Park for this research under Grant No.94061
文摘Mechanical and structural properties of ternary system of TiN-TiO-TiC are investigated using first principle methods. 70 different compositions of Ti100(NOC)100 with cubic structure are examined in order to illustrate the trend of properties variations. The geometry of compounds is optimized, and then, their chemical stability is assessed. Afterward,shear, bulk and young moduli, Cauchy pressure, Zener ratio, hardness and H3/E2 ratio are computed based on elastic constants. Graphical ternary diagram is used to represent the trend of such properties when the content of nitrogen,oxygen and carbon varies. The results show that incorporation of oxygen into the system decreases the hardness and H^3/E^2 ratio while subsequently ductility increases due to positive Cauchy pressure. It is revealed that the maximum H^3/E^2 ratio occurs when both nitrogen and carbon with a little amount of oxygen are incorporated. Ti_(100) N_(30) C_(70) owns the highest hardness and H^3/E^2 ratio equal to 39.5 and 0.2 GPa, respectively. In addition, the G/B of this compound,which is about 0.9, shows it is brittle. It is also observed that the solid solutions have better mechanical properties with respect to titanium nitride and titanium carbide. The obtained results could be used to enhance monolayer coatings as well as to design multilayers with specific mechanical properties.
基金the National Natural Science Foundation of China(NSFC-11475042,NSFC-11505025,NSFC-51377014 and NSFC-21573035).
文摘This study presents spatio-temporal development of the ionisation waves(IWs)along one dielectric tube with an extra alternating electric field.A pulsed direct current power supply is used for generating the IWs,and another alternating current power supply is used for altering the distribution of electric fields along the dielectric tube.The measurements show that the propagation velocity and density of IWs are strongly affected by the external electric field.The direct relation between external electric field and the velocity of the IWs is demonstrated.Further analysis indicates that the external electric field can be utilised to control the propagation of the IWs,resulting in a change of their density and velocity.
