Diamond-like carbon (DLC) films are deposited by the Hall ion source assisted by the mid-frequency unbalanced magnetron sputtering technique. The effects of the substrate voltage bias, the substrate temperature, the...Diamond-like carbon (DLC) films are deposited by the Hall ion source assisted by the mid-frequency unbalanced magnetron sputtering technique. The effects of the substrate voltage bias, the substrate temperature, the Hall discharging current and the argon/nitrogen ratio on the DLC film's performance were studied. The experimental results show that the film's surface roughness, the hardness and the Young's modulus increase firstly and then decrease with the bias voltage incrementally increases. Also when the substrate temperature rises, the surface roughness of the film varies slightly, but its hardness and Young's modulus firstly increase followed by a sharp decrease when the temperature surpassing 120 ℃. With the Hall discharging current incrementally rising, the hardness and Young's modulus of the film decrease and the surface roughness of the film on 316L stainless steel firstly decreased and then remains constant.展开更多
The state of art and future prospects are described for the application of the computational fluid dynamics to engineering purposes.2D and 3D simulations are presented for a flow about a pair of bridges,a flow about a...The state of art and future prospects are described for the application of the computational fluid dynamics to engineering purposes.2D and 3D simulations are presented for a flow about a pair of bridges,a flow about a cylin- der in waves,a flow about an airplane and a ship,a flow past a sphere,a two layers flow and a flow in a wall boundary layer,The choice of grid system and of turbulence modei is discussed.展开更多
文摘Diamond-like carbon (DLC) films are deposited by the Hall ion source assisted by the mid-frequency unbalanced magnetron sputtering technique. The effects of the substrate voltage bias, the substrate temperature, the Hall discharging current and the argon/nitrogen ratio on the DLC film's performance were studied. The experimental results show that the film's surface roughness, the hardness and the Young's modulus increase firstly and then decrease with the bias voltage incrementally increases. Also when the substrate temperature rises, the surface roughness of the film varies slightly, but its hardness and Young's modulus firstly increase followed by a sharp decrease when the temperature surpassing 120 ℃. With the Hall discharging current incrementally rising, the hardness and Young's modulus of the film decrease and the surface roughness of the film on 316L stainless steel firstly decreased and then remains constant.
文摘The state of art and future prospects are described for the application of the computational fluid dynamics to engineering purposes.2D and 3D simulations are presented for a flow about a pair of bridges,a flow about a cylin- der in waves,a flow about an airplane and a ship,a flow past a sphere,a two layers flow and a flow in a wall boundary layer,The choice of grid system and of turbulence modei is discussed.