With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw pl...With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut rock and weakly impr egnated diamonds in weakly impregnated layer make segment expose, then design a new type of layered segment for diamond saw plate.展开更多
Ni-P coated diamond powder was fabricated successfully by using electroless plating.Effects of active solutions,plating time,reaction temperature,and the components of the plating bath on the Ni-P coating were investi...Ni-P coated diamond powder was fabricated successfully by using electroless plating.Effects of active solutions,plating time,reaction temperature,and the components of the plating bath on the Ni-P coating were investigated systematically.Moreover,a study on the thermal stability of Ni-P coated diamond under various atmospheres was performed.The results indicate that Pd atoms absorbed on the diamond surface as active sites can consequently enhance the deposition rate of Ni effectively.The optimized plating bath and reaction conditions improve both the plating speed and the coverage rate of Ni-P electroless plating on the diamond surface.Compared to the diamond substrate,the diamond coated with Ni-P films exhibits very high thermal stability and can be processed up to 900°C in air and 1300°C in protective atmosphere such as H2.展开更多
The coating of Ni W P was deposited as base layer, and then the composite coating of Ni Ti(particles) Re(rare earth) was deposited subsequently on the surface of diamond using electroless plating by adding 2...The coating of Ni W P was deposited as base layer, and then the composite coating of Ni Ti(particles) Re(rare earth) was deposited subsequently on the surface of diamond using electroless plating by adding 2～3 μm Ti particles and trace rare earth salt to bath solution. Ti particles deposited on the surface of diamond were found by SEM and formation of TiC was verified by X ray diffraction analysis after heat treatment of the coatings in vacuum at 900 ℃. The binding strength between the coated diamond and the metal matrix was improved effectively in the diamond composite based on metal cement.展开更多
Diamond-like Carbon (DLC) films have been prepared on Si(100) substrates by arc ion plating in conjunction with pulse bias voltage under H2 atmosphere. The depo sited films have been characterized by scanning electron...Diamond-like Carbon (DLC) films have been prepared on Si(100) substrates by arc ion plating in conjunction with pulse bias voltage under H2 atmosphere. The depo sited films have been characterized by scanning electron microscopy and atomic f orce microscopy. The results show that the surface of the film is smooth and den se without any cracks, and the surface roughness is low. The bonding characteris tic of the films has been studied by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. It shows the sp3 bond content of the film deposited at -200V is 26.7%. The hardness and elastic modulus of the film determined by nanoindent ation technique are 30.8 and 250.1GPa, respectively. The tribological characteri stic of the films reveals that they have low friction coefficient and good wear- resistance. After deposition, the films have been annealed in the range of 350-7 00℃ for 1h in vacuum to investigate the thermal stability. Raman spectra indica te that the ID/IG ratio and G peak position have few detectable changes below 50 0℃. Further increasing the annealing temperature, the hydrogen can be released, the structure rearranges, and the phase transition of sp3 configured carbon to sp2 configured carbon appears.展开更多
文摘With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut rock and weakly impr egnated diamonds in weakly impregnated layer make segment expose, then design a new type of layered segment for diamond saw plate.
基金supported by the National Natural Science Foundation of China (No.50774005)
文摘Ni-P coated diamond powder was fabricated successfully by using electroless plating.Effects of active solutions,plating time,reaction temperature,and the components of the plating bath on the Ni-P coating were investigated systematically.Moreover,a study on the thermal stability of Ni-P coated diamond under various atmospheres was performed.The results indicate that Pd atoms absorbed on the diamond surface as active sites can consequently enhance the deposition rate of Ni effectively.The optimized plating bath and reaction conditions improve both the plating speed and the coverage rate of Ni-P electroless plating on the diamond surface.Compared to the diamond substrate,the diamond coated with Ni-P films exhibits very high thermal stability and can be processed up to 900°C in air and 1300°C in protective atmosphere such as H2.
文摘The coating of Ni W P was deposited as base layer, and then the composite coating of Ni Ti(particles) Re(rare earth) was deposited subsequently on the surface of diamond using electroless plating by adding 2～3 μm Ti particles and trace rare earth salt to bath solution. Ti particles deposited on the surface of diamond were found by SEM and formation of TiC was verified by X ray diffraction analysis after heat treatment of the coatings in vacuum at 900 ℃. The binding strength between the coated diamond and the metal matrix was improved effectively in the diamond composite based on metal cement.
文摘Diamond-like Carbon (DLC) films have been prepared on Si(100) substrates by arc ion plating in conjunction with pulse bias voltage under H2 atmosphere. The depo sited films have been characterized by scanning electron microscopy and atomic f orce microscopy. The results show that the surface of the film is smooth and den se without any cracks, and the surface roughness is low. The bonding characteris tic of the films has been studied by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. It shows the sp3 bond content of the film deposited at -200V is 26.7%. The hardness and elastic modulus of the film determined by nanoindent ation technique are 30.8 and 250.1GPa, respectively. The tribological characteri stic of the films reveals that they have low friction coefficient and good wear- resistance. After deposition, the films have been annealed in the range of 350-7 00℃ for 1h in vacuum to investigate the thermal stability. Raman spectra indica te that the ID/IG ratio and G peak position have few detectable changes below 50 0℃. Further increasing the annealing temperature, the hydrogen can be released, the structure rearranges, and the phase transition of sp3 configured carbon to sp2 configured carbon appears.
