Abrasive slurry jets (ASJ) and abrasive waterjets (AWJ) offer a low temperature, low damage method for machining titanium. However to achieve the required precision both in cutting and milling of materials, abrasive waterjet systems must operate within well defined performance parameters. In order to define these parameters a series of experiments are described using the titanium alloy Ti6Al4V. Two different applications formed the initial focus for the investigation. The first is the ability to precisely cut holes, and the second relates to the precision milling of pockets in the target surface. For both operations, the accuracy of verticality of the walls cut forms an important control on acceptable performance. Tests to determine the effect of cutting speed on wall quality have shown an interesting result. As cutting speed increases wall quality decreases, to a certain point, and then with further increase in speed begins to increase again. Optimizing performance therefore can potentially not only meet the verticality criterion, but also achieve other required goals of cutting performance. The relationships between surface quality, geometrical features and machining parameters thus become an integrated suite of interactions, that continue to be defined as a function of target material and geometry. Surface roughness and microstructural surface features are a critical aspect of acceptable quality. The operational requirements to achieve defined standards of surface roughness and hole tolerance are discussed, with illustrations as to how they may be achieved.
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