Papers by Keyword: Wire Saw

Abstract: The structural characteristics of the tensioning device in the wire saw manufacturing equipment is introduced. Based on the characteristic of the strainer, the principle of variable universe fuzzy control is adopted to deal with the controlling objects. The design of two stage fuzzy controller and its parameters are discussed. The system simulation shows that the control scheme can make the tension within the stable range.

Abstract: Nowadays, wire sawing becomes the most advanced brittle crystals slicing technology because of its advantages of slicing larger crystals ingots into very small thickness, high surface quality, high yield wafers. In the process, the thin wire, which is the processing tools, travels at high speed, and subjects to external excitation from many aspects. Wire saw tension control is the core and difficulty of the control system. Mathematical models of tension subsystems were studied. The control strategy of swing arm motor tension direct closed-loop combination of speed difference indirect closed-loop was proposed. The developed tension control hardware and software system reached the functional requirements and technical indicators, and constant tension precision control was solved effectively.

Abstract: The wire saw for slicing wafers process is free abrasive machining process. In this paper, we summarize the sawing mechanism for free abrasive wire saw, and think that the sawing mechanism is mainly rolling-indenting removal. But there are two forms of the force which causing the abrasives to roll and indent in the workpiece surface, one form the force acts on the abrasives by shear stress and hydrodynamic pressure, another form the force acts on the abrasives by wire saw. We design an experiment to verify the form of the force, and think that the second form of the force mainly causes the abrasive to roll and indent in the workpiece surface.

Abstract: Solar photovoltaic cell demand is great in the whole world and its manufacturing cost is also high. The main reason that slicing cost is too high, because of the low slicing efficiency and large kerf loss.Therefore, many scholars are studying new slicing method in order to reduce the cost. In this paper, we summarize conventional and new slicing method for solar silicon wafer, and think that new slicing method widely apply in photovoltaic industry, which needs to solve some technical problems. At present, multi-wire saw technology still is mainly slicing method in photovoltaic industry.

Abstract: This paper introduces the structure of the resin bonded abrasive wire saw manufacture equipment. The equipment can complete the process of the wire saw production, including uncoiling wire, cleaning wire, binder coating, Pre-curving and coiling wire. Wire saw are manufactured successfully by this equipment in the manufacture experiment. The quality of the wire saw was examined by SEM. The average slicing ability of the wire saw is 205 mm2 per meter in the experiment of KDP crystal slicing.

Abstract: A new high frequency induction brazed monolayer diamond wire saw for cutting aluminum alloy thick plate is developed with the helical continuous cutting edge distance on the wire surface. In order to solve the problems of forming cutting aluminum alloy plates,the brazed diamond wire saw is used to conduct the preliminary cutting tests on the 50 mm aluminum alloy plates on the modified grinder experimental platform.The results indicate that the cutting efficiency of the brazed diamond wire saw is increased with the increasing of the feed tension, the wire saw line speed and the diamond grits size. Furthermore, some cutting chips shape of the aluminum alloy is presented based on experimental cutting.

Abstract: Fixed-abrasive diamond wire saw is widely used for slicing semiconductor materials. In this paper, a novel manufacturing method is studied by using polyethylene wire to replace the traditional metallic core wire. A new coating device of ultraviolet-curing for rapidly making diamond wire saw is developed. In terms of tensile strength experiments’ results, a high strength polyethylene multi-strand wire is finally selected as the core wire of the fixed-abrasive wire saws. Experimental results show that the high tensile strength of polyethylene multi-strand wire can satisfy the technical requirements of fixed-abrasive wire saws.

Abstract: Wire saw has a unique benefit in cutting precious material like SiC, Si monocrystal and gem etc since the cutting force is small, and the kerf loss is low and so on. In the common wire saw cutting process, the production efficiency is low, the wire saw wear is dramatic severe, the surface roughness of part is not expected and collapses flaws often occur on wafer as well, all those problems have a heavy effectiveness on wafer quality. In order to solve those problem, the ultrasonic vibration machining (UVM) has been applied to cut the hard & brittle materials which has a significant improvement on surface integrity of wafer and increasingly apply to nonconductive materials cutting, such as glass, ceramics, Si, gem and so on. In this paper, the cutting force for SiC monocrystal wafer by wire saw with UVM is studied, the mathematic model of cutting force for wire saw with UVM is discussed and the Fourier series expansion is used to solve the equation of cutting force. The experiments that the process parameters influence on the cutting force by common wire saw cutting and wire saw with UVM are conducted, respectively. The result show that wire saw with UVM can significantly decrease the cutting force, which is consistent with the theoretical analysis.

Abstract: A wire-saw cut KDP crystal geometrical model was founded and a mathematical model was established to calculate the grit average cut depth, based on indentation fracture mechanics theory(IFMT). The relationship between the grit cut depth and wire saw process parameter was analyzed theoretically. The research results indicate that there exists an approximate monotone increasing non-linear correlation between grit average cut depth and the ratio i value of crystal feed speed and wire speed. By increasing the wire speed and crystal feed speed accordantly, the value of i can be maintained invariable, however, this way can simultaneously bring higher machined surface quality and machining efficiency.

Abstract: A mathematical model to calculate the grit average cut depth in wire sawing single crystal silicon was founded. So the grit average cut depths were calculated theoretically by choosing different process parameters, and influences of process parameters on grit cut depths of slicing silicon crystal were analyzed. Analysis results indicate that the grit average cut depth relates to the silicon mechanical properties, grit shape and size, wire speed and ingot feed speed, etc. And there is a monotone increasing non-linear correlation between grit average cut depth and the ratio i value of ingot feed speed and wire speed, when the i value is lower, the average grit cut depth is lower.