The heat generated during the cutting process of titanium alloys and superalloys is a significant limitation that affects machining quality. Excessive heat can accelerate tool wear, increase cutting forces, alter material properties, and decrease productivity. To address this issue, alternative cooling techniques have been suggested to minimize heat generation during cutting. Among these alternatives, internal cooling techniques have emerged as a more efficient and cost-effective solution. This paper provides a comprehensive review of internal cooling techniques in the cutting process, including their effects on cutting fluid flow, chip formation, cutting temperature, cutting forces, surface roughness, tool wear, and chip morphology. The paper also presents methods to enhance cooling and lubrication performance by optimizing the internal cooling channels and outlet nozzles of cutting tools, as well as selecting appropriate fluid supply pressure. Additionally, the paper highlights important considerations when using internal cooling techniques and proposes future directions for their development, taking into account existing challenges.

The tube spinning process has attracted much attention because of its simple tooling and good surface finish. This review presents a comprehensive survey of the tube spinning process with a focus on different tube blank materials and spinning methods. The review aims to elaborate the research status of tube spinning process from the aspects of tube material, spinning method and processing performance, and act as a guide for researchers working on tube production and spinning process. In addition, the spinning process will produce large plastic deformation, which will lead to the change of the microstructure of the tube and change its mechanical properties. Therefore, the relationship between the mechanical properties of the tube blank and the spinning parameters is comprehensively expounded from the aspects of yield strength, elongation and material microstructure, and the element diffusion and interface bonding mechanism in the spinning process of the composite tubes are emphatically introduced. In particular, the latest development and trend of composite materials and composite spinning process in tube blank spinning process are discussed. The challenges and prospects of the development of the tube spinning process are put forward, and the direction for future research is pointed out.

Arc wire-based Direct Energy Deposition (DED) technology is an essential additive manufacturing process that exhibits a high deposition rate and heat accumulation. This technology is advantageous due to its efficient production at a low cost. The process utilizes an electric arc for heat source and metal wire for feed material. After path planning, it creates three-dimensional metal parts layer by layer. In order to prevent defects from affecting the service condition and lifespan of the parts, it is crucial to focus on the evolution of the microstructure and the enhancement of the mechanical properties during the deposition process. During metal parts manufacturing using Arc wire-based DED, defects such as residual stresses, porosity, deformation, and cracking are generated due to the complex thermal cycle and high heat input. This paper provides a concise overview of the process and methodology involved in Arc wire-based DED, along with an analysis of the resulting microstructure and material properties. This review also outlines means of controlling the heat input, as well as pre-treatment, in-process, and post-treatment methods for controlling the defects and microstructure to improve the properties of the workpieces. Finally, the paper offers insights into achieving high-quality, defect-free workpieces using Arc wire-based DED and provides recommendations for future DED development.