![]() ![]() Single-/multi-pocket parts were milled from 7050-T7451 aluminium blocks with different initial residual stress, and an element deletion method was developed for numerical study to simulate different sequences of material removal. This work investigated the distortion attributed by the initial residual stress of raw material and the machining induced residual stress during the milling process, as well as explored the effects of the machining toolpath strategy. Monolithic aluminium alloy parts are highly required in aeronautical industry, but they show significant geometrical distortion after the machining process. In addition, reasonable micro-texture parameters can obtain better surface quality of the workpiece. The micro-texture in the slip zone can improve the chip curl and promote the stability of the system. The micro-texture in the bonding zone can reduce the tool-chip contact area, improve the friction state, increase the heat dissipation area, and reduce the plastic deformation of titanium alloy. The results show that the variable distribution density micro-texture has a positive effect on improving the machining quality of titanium alloy. Finally, based on the hierarchical structure weight method and fuzzy comprehensive evaluation theory, the integrity of the machined surface is comprehensively evaluated and the micro-texture parameters are optimized. Secondly, a milling titanium alloy test platform was built to reveal the change law and mechanism of micro-texture parameters on the machined surface integrity. Firstly, based on the ball end milling model of titanium alloy, a variable density micro-texture model is established in the chip contact region. In order to improve the service performance and machining efficiency of titanium alloy, the concept of variable distribution density micro-textured ball end milling cutter is proposed based on texture effect. ![]() The surface integrity of machined workpiece is an important index to evaluate the service performance of parts. The constraint jig and welding processes designed for QTT are effective and feasible. The results show that there are no obvious defects in the welds of the azimuth track. Finally, nondestructive testing was carried out to check the welding quality of the track surface and interior. The results show that the opposite deformation jig designed for QTT’s azimuth track can make the amount of deformation and flatness meet the design requirements. The three deformation processes of the track are regulated by the opposite deformation jig. The simulation results show that a better welding effect will be obtained by appropriately reducing the opposite force on the basis of the original. Then, the welding process was numerically simulated using a finite element model. First, the opposite deformation jig and welding process were designed for the QTT’s azimuth track. It is hoped that the data provided in this review will serve as a valuable up‐to‐date reference for engineers and scientists in the field of residual stress.Ĭonsidering the stringent requirement of the pointing accuracy up to 2.5″ of the world’s largest full steerable radio telescope, this paper studies the welding experiment of the azimuth track of the antenna. The third section summarizes various strategies to effectively control residual stresses through different manufacturing procedures. The range of topics covered are “welding, machining, curing/cooling, and spray coating processes”, “medical and dental sciences”, and “fatigue and fracture mechanisms”. ![]() This is presented by classifying different science areas dealing with residual stresses into two main groups, including ‘origins’ and ‘effects’ of residual stresses. The second section includes the role of residual stresses in the performance of a broad range of materials including metallic alloys, polymers, ceramics, composites, and biomaterials. The first section covers different residual stress determination methods and reports the advancements over the recent decade. This review paper contains three main sections. In this regard, the industry requests rapid, efficient, and modern methods to identify and control the residual stress state. Moreover, the residual stress management concept contributes to industrial applications aiming to improve the product’s service performance and life cycle. The accurate determination of residual stresses has a crucial role in understanding the complex interactions between microstructure, mechanical state, mode(s) of failure, and structural integrity. ![]()
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