Research On The Characteristic And The Process Performance Of Semi-Fixed Abrasive Plate

With the development of information technology, photoelectron technology and aerospace technology, the requirement of process is more and more higher, and the need of process which has the performance of high efficiency, high precision and low surface damage keeps increasing. There mainly are two abrasive particle process which includes fixed abrasive process and loose abrasive process in the existing ultra-precision machining techniques, preventing such surface defects as scratch and crack and improving finish efficiency is a pair of contradiction. The research center puts forward semi-fixed abrasive machining technology which integrates fixed abrasive machining and loose abrasive machining. The key of the novel technique is using semi-fixed abrasive plate(SFAP) with 'trap effect' for ultra-precision machining.The article refers to the conventional abrasive tool's manufacturing processes, according to characteristics of the semi-fixed abrasive plate, we improve the semi-fixed abrasive plate's manufacturing process, and also propose the perfect processing process .With the study of combination and additives, the suitable formula for a semi-fixed abrasive plate is determined.According the respective characteristic of traditional abrasive lapping tool's parameters, the experiment scheme is ensured. The major parameters are detected and evaluated, such as hardness,, holding capacity to slurry, shear strength, compressive modulus of elasticity, etc. The basic characteristic of semi-fixed abrasive plate that can be used to ultra-precision machining is confirmed. With the use of CCD, SEM and 3-Dimension microscope, the micro structure of the plate is observed, the suitably bonding and its concentration is acquired.With the Nanopoli-100 precision grinding/polishing machine, the silicon wafer, copper substrate and stainless steel is adopted to testing the process performance of the semi-fixed abrasive plate. Four kinds of plates are used, which includes the plates with different bonding agent, the plates with different bonding concentration, the plates with different abrasive size, the plates with different mixed abrasive size. The resin bonding semi-fixed abrasive plate with concentration of 35% is the best.Orthogonal experiments are used to analyzing the affect of the process parameters to the silicon wafer's remove rate and surface roughness. The range of the process parameters, such as the abrasive size, the pressure on the wafer, the velocity of plate and the flow rate of slurry etc is confirmed. The effects of process parameters and material remove rate along with the average roughness of wafer are discussed by one element experiment method, and corresponding curve relationship is achieved. A semi-fixed abrasive machining experiment is carried out with the optimal parameters and compared with the loose abrasive under the same processing conditions, copper substrate and stainless steel is used as workpieces. The experiment results show that the removal efficiency is nearly the same in the two kinds of machining technology, but the Ra value of workpieces surface machined by semi-fixed abrasive plate is much lower than machined by traditional loose abrasive. The surface damage of the workpieces is much lower than loose abrasive machining, then the polishing process is shorter, and process performance is improved. It proves the advantage of the machining characters employing semi-fixed abrasive machining.