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Laser deposition manufacturing (LDM) technology provides the potential to manufacture large, difficult-to-process metal components for aerospace and other applications. However, the residual stresses resulting from the considerable temperature gradients in the LDM process can lead to distortion and even cracking of the fabricated components. Rapidly predicting the distortion for large additive metal components is critical to controlling the distortion and achieving high-quality forming of large components. Considering the principle of LDM technology, the partitioning method based on typical geometric features for aerospace titanium alloy frames, beams, and wall plates is proposed in this paper. It establishes a rapid prediction method for distortion of large additive metal components based on feature partitioning and temperature function method (TFM) by considering the effect of critical parameters of temperature function on distortion prediction. The results show that the prediction of additive component distortion through this method agrees with the results predicted by the traditional method and experimental results. Furthermore, the computational efficiency of the method has improved by 96% compared to the traditional approach, meeting the need for rapid distortion prediction in large metal additive components. [ABSTRACT FROM AUTHOR]

The intermittent cutting behavior, performing as periodic contact phase and separation phase between abrasive grit and workpiece, is an important characteristic in the ultrasonic vibration-assisted grinding (UVAG). This study investigated the effect of intermittent cutting behavior on the grinding force in UVAG. At first, a grinding force model was established by determining the quantity of effective grits and the grinding force of a single grit. Then, the influences of ultrasonic vibration phase on the intermittent cutting behavior and grinding force were discussed. Finally, the prediction accuracy of the model was tested through experiments. Results indicated that the intermittent cutting behavior was divided into the contact phase and separation phase. A large unchanged chip thickness of 1.05 μm was generated at the start of contact phase. The quantity of effective grits firstly increased to maximum 232 at the vibration phase of 0.5 π and then gradually decreased to zero when entering the separation phase. The maximum error of the grinding force model was 15%, indicating that the model was of high accuracy for the force prediction in UVAG. [ABSTRACT FROM AUTHOR]