| dc.description.abstract | In today′s manufacturing industry, wire-sawing technology is widely applied in processing hard and brittle materials, such as ceramics, glass, sapphire, and silicon ingots. These processing techniques are crucial for producing high-quality products. However, the manufacturing process also comes with a series of challenges and problems, including increased damage rates, poor surface quality of materials, presence of residual stresses, and optimization of processing parameters. This study first proposes the coupled model of the Discrete Element Method (DEM) and particle bonding theory to investigate the physical mechanisms of wire sawing. The influence of processing parameters on the physical and surface properties of wafers was systematically explored. This innovative simulation approach provided insights into the behavior of the machining processes. The acquired physical properties included forces and moments on the wire, material removal rates, wafer surface quality (total thickness variation and warpage), internal residual stresses, coordination numbers, and solid volume fraction. To attain reasonable simulation results, uniaxial compression tests for bulk solids were conducted, and the methodology of Design of Experiment (DOE) was used to determine the microscopic input parameters for DEM.
Main research findings are summarized below: (1) The total thickness variation (TTV) is more uniform in the cutting direction than in the vertical direction, and the wafer warpage is flatter in the cutting direction; (2) As the sawing velocity increases, wire forces and moments gradually decrease, while wafer residual stresses and removal rates increase. Moreover, larger sawing velocities result in more uniform TTV and flatter warpage; (3) With the increase of feeding velocity, wire forces, wire moments, and removal rates gradually increase, while wafer residual stresses decrease; (4) An increase in the velocity ratio leads to a gradual increase in the wire forces and moments, but a decrease in the residual stresses; (5) The wire forces, wire moments, and wafer residual stresses generally increase with the size of the silicon ingot. | en_US |