| Special vehicles have demanded higher mobility and barrier properties for the development of offense weapons in modern conflict. Since engineering ceramics and fibre reinforced composites are characterized of low density and excellent barrier propterties, high performance lightweight composite components made of them have wide application prospect. Usually, after the composite components are manufactured, secondary machining processes such as drilling, slotting are required for the purpose of joining and assembling. Engineering ceremics and fibre reinforced composite are belong to "difficult to cut" materials and the composite components made of the two will be more difficult to cut for their totally different machinability. The difficulty has limited their application. This paper is devoted to study intensive and systematical technologies to process the high performance composite components, which could provide technical supports for its broader application.Firstly, cutting tools and processing technology were analized. For the ceramic composite component, manufacturing technology of diamond tools including sintering, electroplating and brazing was analyzed; for the glass fiber reinforced plastics (GFRP) composite component, twist drills inculing TiN-coating, multi-edge tip, S-shaped tip and PCD types were used to conduct the experiments. By designing a pretightening force component, optimizing processing sequence of the ceramic composite component and adopting different coolling methods, machining quality of the composite components is improved.Secondly, machining mechanisms of the composite components and tool wear were studied. By using indentation fracture mechanics and ceramic cutting model, examining the ground surfaces by scanning electron microscope (SEM), the ceramic removal mechanisms, machined surface characteristics of GFRP and tool wear were analized. The results show that the ground surface of the armor ceramic consists of fractured area and ductile streak area, which indicate that the material removal modes include brittle fracture and ductile cutting, which is called "mixed removal modes", and the brittle fracture removal is much more prevalent; for the grinding process of GFRP, fibers are broken by shear behavior of abrasive grain and six type of broken morphology are found; for the cutting process, fibers are broken by shear behavior of the main edge of the twist drill and three type of broken morphology are found; Both the surface consist of glass firber aera and resin coated area; diamond wear is caused by cutting force and cutting heat; sintering bit converting phase is caused by the difference of cutting load working on the bit outside and inside diameters; sintering bit skidding results from diamond wearing smoothly; sintering tools form wear topography of " drifting sand " mode, which does not present in electroplating and brazing ones.Thirdly, experimental researches were conducted for the composite components. For the alumina composite component, with diamond SMD40 and matrix Cu50Co25Sn18Ti7(wt%) being adopted, the matrix performance was improved, then bit structure parameters were optimized by an orthogonal experiment. The results show that the bit with wall thickness of 2.5mm, diamond grain of 35/40, diamond concentration of 100% and 3 of the slots can obtain a high drilling efficiency. Milling tests were conducted by using the performance improved diamond tools and the main influcing factors to the efficiency were analized. The results show that the ascending order is feeding force, milling depth and spindle speed. For the silicon carbide ceramic, sintering, brazing and electroplating diamond bits were used to conduct drill tests, with the best performing bit being chosed, and by conducting single factor experiments, the influence of axial force and spindle speed to the efficiency was analized. The results show that electroplating bits present the best performance,800N and 2600r/min are not suitable to exceed under the experimental conditions, and two side drilling could obtain qualified holes.For the GFRP composite components, the influence of the pretightening force, chisel edge, TiN coat and drill diameter to the thrust force and delamination was analized, thrust force empirical equations of feed rate, spindle speed and drill diameter were built. S shaped tip drill with TiN coated and PCD drills were also used to analyze their influence to the thrust force and delamination; with critical thrust force model being built, conclusions were made that PCD drill could obtain the best drilling quality and the longest tool life among the drills.Finally, portable hole-drilling equipment of diamond drill machine was modified. A kind of vacuum base to the machine was designed. Seal material and sealing technology were studied; sealing property of the vacuum base was analized by finite element methods; drilling tests were conducted to verify the reliability of the modified equipment. The results show that with using the vacuum base (seal material, nitrile rubber, hardness HA 60), the Portable hole-drilling equipment is dependable, and could realize the spot process with no destroying surface of the composite component.
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