A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore,it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity l...A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore,it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity loss.It has been applied to a national military standard since July 1,2004.展开更多
The ultra-precision machining process using a single crystal diamond tool has been mainly used for machining molds of optical components.Since the micro patterns of various shapes having excellent surface roughness ca...The ultra-precision machining process using a single crystal diamond tool has been mainly used for machining molds of optical components.Since the micro patterns of various shapes having excellent surface roughness can be machined by using ultra-precision machine tools,the micro pattern on a large light guide plate (LGP) is mainly machined using a diamond tool.The tool wear occurs due to long machining distances and time while machining a large-area LGP mold.The deformation and dimensional error of micro pattern are caused by tool wear,as a result,the light efficiency of LGP declines.The characteristics of tool wear should be analyzed in order to precisely machine large-area LGP mold from all sorts of materials.The experiments were performed in order to compare wear characteristics of a V90° diamond tool using Al3003,5052,6061 and 7075.The prism pattern of depth 10 μm was machined in order to analyze characteristics of tool wear according to machining distances (0.5,1 and 1.5 km).The effects of tool wear on pattern shape were analyzed by applying overlapped cutting depths (Rough machining is (10+8+7) μm and Finish machining is (5+3+2+1) μm) by continuously machining a prism pattern of W shape of 25 μm in depth.展开更多
Under spinning conditions, lubricant on islandic spot patterned M2 steel disc experiences centrifugal and tangential force components. Depending upon the relative position of the spots and the flow of lubricant, accum...Under spinning conditions, lubricant on islandic spot patterned M2 steel disc experiences centrifugal and tangential force components. Depending upon the relative position of the spots and the flow of lubricant, accumulation of lubricant in front of patterned islandic spots creates thrusting to mating part and subsequently reduces contact between the mating couple. Whilst wear debris is likely to be spun off the plateau of the spots to their neighbouring valleys so as to reduce wear. Hence, it gives favorable tribological characteristics. Aiming at verifying such mechanisms, studies were performed on M2 steel disc specimens slid with ASSAB 17 tool steel pin. The M2 steel disc specimens were respectively （i） machined with non-patterned （NP）, （ii） etched to produce in-lined （INE） islandic patterns, and （iii） etched to produce staggered （STE） islandic spot patterns. Results indicated that the INE patterned discs gave most favorable wear characteristics, the NP of the worse characteristics whilst the STE ranged in the middle. However, the actual contact mechanism leads to the descending sequence of favorable friction behaviors nominally as： NP, INE and STE.展开更多
A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical ...A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical parameters combined by its shape, color and surface texture features through a computer vision system. Those features were used as input vector of artificial neural network for wear debris identification. A radius basis function (RBF) network based model suitable for wear debris recognition was established, and its algorithm was presented in detail. Compared with traditional recognition methods, the RBF network model is faster in convergence, and higher in accuracy.展开更多
文摘A method to determine muzzle velocity loss according to the actual measured bore wear pattern is proposed.Therefore,it is unnecessary to conduct live firing and other experiments for determination of muzzle velocity loss.It has been applied to a national military standard since July 1,2004.
文摘The ultra-precision machining process using a single crystal diamond tool has been mainly used for machining molds of optical components.Since the micro patterns of various shapes having excellent surface roughness can be machined by using ultra-precision machine tools,the micro pattern on a large light guide plate (LGP) is mainly machined using a diamond tool.The tool wear occurs due to long machining distances and time while machining a large-area LGP mold.The deformation and dimensional error of micro pattern are caused by tool wear,as a result,the light efficiency of LGP declines.The characteristics of tool wear should be analyzed in order to precisely machine large-area LGP mold from all sorts of materials.The experiments were performed in order to compare wear characteristics of a V90° diamond tool using Al3003,5052,6061 and 7075.The prism pattern of depth 10 μm was machined in order to analyze characteristics of tool wear according to machining distances (0.5,1 and 1.5 km).The effects of tool wear on pattern shape were analyzed by applying overlapped cutting depths (Rough machining is (10+8+7) μm and Finish machining is (5+3+2+1) μm) by continuously machining a prism pattern of W shape of 25 μm in depth.
基金the National Natural Science Foundation of China(No. 50575173).
文摘Under spinning conditions, lubricant on islandic spot patterned M2 steel disc experiences centrifugal and tangential force components. Depending upon the relative position of the spots and the flow of lubricant, accumulation of lubricant in front of patterned islandic spots creates thrusting to mating part and subsequently reduces contact between the mating couple. Whilst wear debris is likely to be spun off the plateau of the spots to their neighbouring valleys so as to reduce wear. Hence, it gives favorable tribological characteristics. Aiming at verifying such mechanisms, studies were performed on M2 steel disc specimens slid with ASSAB 17 tool steel pin. The M2 steel disc specimens were respectively （i） machined with non-patterned （NP）, （ii） etched to produce in-lined （INE） islandic patterns, and （iii） etched to produce staggered （STE） islandic spot patterns. Results indicated that the INE patterned discs gave most favorable wear characteristics, the NP of the worse characteristics whilst the STE ranged in the middle. However, the actual contact mechanism leads to the descending sequence of favorable friction behaviors nominally as： NP, INE and STE.
文摘A method and results of identification of wear debris using their morphological features are presented. The color images of wear debris were used as initial data. Each particle was characterized by a set of numerical parameters combined by its shape, color and surface texture features through a computer vision system. Those features were used as input vector of artificial neural network for wear debris identification. A radius basis function (RBF) network based model suitable for wear debris recognition was established, and its algorithm was presented in detail. Compared with traditional recognition methods, the RBF network model is faster in convergence, and higher in accuracy.
