Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperatur...Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperature in cutting area to enhance tool life, it is the largest source of environmental pollution. To develop a technology for the clean and efficient milling Ti alloys, nitrogen gas is used as a cutting media in this paper. Based on lots of experiments and researches, the tool life and wear mechanism of high speed steel miller is analyzed. A conclusion is drawn that, milling with nitrogen gas media yields much longer tool life than dry milling. Tool life equations (Taylor′s equations) are derived for both milling types.展开更多
A numerical simulation model is proposed to predict the wear depth of gears,where Archard's wear equation and a nonlinear dynamic model are combined to establish a wear calculation model under dynamic conditions.T...A numerical simulation model is proposed to predict the wear depth of gears,where Archard's wear equation and a nonlinear dynamic model are combined to establish a wear calculation model under dynamic conditions.The dynamic meshing force,determined by the non-linear dynamic model,and the sliding coefficient are used by Archard's wear equation to calculate the surface wear.Then the dynamic meshing force and sliding coefficient would be recalculated according to the surface wear state.After repeated iterations,the simulation results show that the peak and fluctuation of the meshing force increase first,then decrease,and eventually maintain stability during the process of wear.As for the distribution of wear depth,its fluctuation also increases first and then declines.Finally,the distribution of wear depth becomes V-shaped.Comparing the trends of the two factors,it is clear that the meshing force and wear depth are closely related.Moreover,the wear rate maintains a higher constant value first and then declines to a lower constant value.展开更多
文摘Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperature in cutting area to enhance tool life, it is the largest source of environmental pollution. To develop a technology for the clean and efficient milling Ti alloys, nitrogen gas is used as a cutting media in this paper. Based on lots of experiments and researches, the tool life and wear mechanism of high speed steel miller is analyzed. A conclusion is drawn that, milling with nitrogen gas media yields much longer tool life than dry milling. Tool life equations (Taylor′s equations) are derived for both milling types.
基金Supported by the National Natural Science Foundation of China(51475044)
文摘A numerical simulation model is proposed to predict the wear depth of gears,where Archard's wear equation and a nonlinear dynamic model are combined to establish a wear calculation model under dynamic conditions.The dynamic meshing force,determined by the non-linear dynamic model,and the sliding coefficient are used by Archard's wear equation to calculate the surface wear.Then the dynamic meshing force and sliding coefficient would be recalculated according to the surface wear state.After repeated iterations,the simulation results show that the peak and fluctuation of the meshing force increase first,then decrease,and eventually maintain stability during the process of wear.As for the distribution of wear depth,its fluctuation also increases first and then declines.Finally,the distribution of wear depth becomes V-shaped.Comparing the trends of the two factors,it is clear that the meshing force and wear depth are closely related.Moreover,the wear rate maintains a higher constant value first and then declines to a lower constant value.