Continuous fiber-reinforced metal matrix composites (CFMMCs) are increasingly utilized in high-performance aerospace engines because of their exceptional strength along the fiber axis. Unlike particle-reinforced metal matrix composites (PMMCs), CFMMCs exhibit significant anisotropic properties, which complicate their machining processes. While extensive studies have focused on tool wear in PMMCs, a notable research gap exists regarding the grinding removal mechanisms and grain wear behaviors in CFMMCs, particularly in the context of ultrasonic vibration-assisted grinding (UVAG). This study addresses this gap by investigating grain wear along different fiber orientations—perpendicular fiber (PF), transverse fiber (TF), and longitudinal fiber (LF)—through single-grain grinding experiments on SiC fiber-reinforced Ti–5Al–2Sn–2Zr–4Mo–4Cr (TC17) matrix composites (SiC_f/TC17). A detailed analysis of surface morphologies within the grinding scratches was conducted, revealing significant differences in cubic boron nitride (CBN) grain wear patterns under different fiber orientations, particularly when UVAG was compared with conventional grinding (CG). The results indicate that ultrasonic vibration effectively mitigates fiber fracture and grain wear, with the most severe grain wear and adhesion occurring when grinding along the LF orientation. This research not only advances the understanding of CFMMC grinding mechanisms but also contributes to enhancing the machinability of CFMMCs, thereby facilitating their broader application in aerospace and other high-performance industries.

Traditional tools have limited adaptability in complex machining environments due to their lack of working-condition perception and autonomous regulation. With advances in sensors, materials, and data-processing technologies, tool design is shifting from a single-function ‘mechanical arm’ for cutting towards integrated intelligent terminals. This paper systematically reviews progress in intelligent tool technology from two perspectives: design and regulation. For intelligent design, the fundamental principles of condition-perception tools equipped with built-in multi-type sensors are discussed, enabling in situ, real-time monitoring of multidimensional parameters such as cutting force, temperature, and vibration. Force monitoring is achieved through elastic deformation or dynamic charge response, temperature monitoring through the thermoelectric effect, and vibration monitoring through micro-displacement and intensity detection. The design focus emphasises sensor miniaturisation and integration, balancing measurement accuracy with tool stiffness while minimising machining interference. In regulation, key technologies for constructing closed-loop control systems (CLCS) are summarised, which dynamically adjust cutting speed, feed rate, and other parameters based on sensed data, achieving precise control of force, temperature, and vibration via feedback mechanisms and driving units. Breakthroughs in tool wear compensation (TWC) mechanisms are introduced. Multi-source signal fusion combined with deep learning algorithms is further examined for improving monitoring accuracy and remaining useful life (RUL) prediction. Through model predictive control, intelligent regulation of cutting parameters within process flows is realised. Finally, challenges such as sensor reliability, multi-source coupling, and balancing cost with industrial applicability are analysed. Future directions highlight novel structural designs, high-performance material development, and multi-technology integration, aiming to establish a fully intelligent machining system through the integrated design of ‘perception-decision-execution’.

Advanced manufacturing theory and technology are the cornerstone of technological progress and social development, as well as the foundation for supporting the aerospace industry and national defense construction. They are also the key to promoting innovation in high-end equipment. However, with the development of new materials and new structures, traditional manufacturing techniques are unable to meet the processing requirements of key components in the aerospace industry. Therefore, advanced manufacturing theory and technology have become an important research direction in the aerospace field, experiencing rapid development. This paper first introduces the connotation and characteristics of advanced manufacturing theory and technology in aerospace. Besides, it summarizes the basic principles, application areas, and application material scope of typical advanced manufacturing theories and technologies in the aerospace field, such as high/ultra-high speed machining, precision forming manufacturing, micro and nano machining, atomic and near atomic scale machining, modern special machining, rapid prototyping manufacturing, and green manufacturing. Secondly, the latest research progress in advanced manufacturing theory and technology is summarized, Including high speed and efficient machining technology, high performance composite machining technology, intelligent control machining technology, large scale, miniaturization, and emerging material technology. Then, the main challenges and future development trends faced by current advanced manufacturing theories and technologies are discussed in depth. Subsequently, the engineering application and design manufacturing integration of advanced manufacturing theory and technology are elaborated, and its important position in the aerospace manufacturing field is emphasized. Finally, the frontier fields involved in the new generation of advanced manufacturing theory and technology in aviation and aerospace are analyzed, and the principal development points for the future are clarified, the pivotal development directions are indicated.

Continuous Fiber-reinforced Metal Matrix Composites (CFMMCs), such as SiC fiber-reinforced TC17 matrix composites (SiC_f/TC17), are renowned for their exceptional mechanical properties. However, their heterogeneous compositions present significant machining challenges, including fiber pullout, matrix cracking, and accelerated tool wear. Ultrasonic Vibration-Assisted Grinding (UVAG) has proven to be an effective technique for overcoming these challenges. The material removal mechanisms in UVAG, especially in composites with both ductile and brittle phases, remain poorly understood. To explore these issues, UVAG and Conventional Grinding (CG) experiments were conducted on SiC_f/TC17 along two grinding directions: fiber’s transverse direction (FT) and fiber’s longitudinal direction (FL). This paper aims to provide a new dynamic mechanical model and shed light on the complex removal mechanisms in CFMMCs, which are characterized by a near one-to-one alternation of ductile and brittle phases. The findings reveal that UVAG reduces fiber damage and surface roughness compared to CG, especially when grinding along FT. UVAG lowers normal (F_n) and tangential grinding forces (F_t) by 15.3% and 12.3%, respectively. This highlights UVAG’s potential for improving the machinability of complex materials like CFMMCs. The proposed grinding force model closely matches the experimental results. This paper hopes to support the precision abrasive machining of CFMMCs, a kind of complex and highly anisotropic composite material, and promote their application in the fields such as aerospace.

The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace, military, and medical sectors. However, conventional machining of titanium alloys leads to elevated tool wear, development of surface defects, and reduced machining efficiency due to their low heat conductivity, and chemical affinity. These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability. This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces, temperature, tool wear, and surface integrity, encompassing surface morphology, surface roughness, surface residual stress, surface hardness, and surface tribological properties during titanium alloys machining. Furthermore, it investigates the sustainability aspect that has not been previously examined. Studies on the performance of ultrasonic-assisted cutting revealed several advantages, including decreased cutting forces and cutting temperature, improved tool life, and a better-machined surface during machining. Consequently, the sustainability factor is improved due to minimized energy consumption and residual waste. In conclusion, the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed. This review article provides beneficial knowledge for manufacturers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry.

Gamma titanium-aluminum (γ-TiAl) intermetallic compounds are increasingly used in manufacturing key hot-end components (e.g., blade tenon) in aero engines due to their high specific strength and lightweight properties. Creep feed profile grinding (CFPG) as a crucial precision process that is applied to produce the final profile of the blade tenon. However, sudden surface burns and microcracks of machined γ-TiAl blade tenon often occur because of its low plasticity and high strength during grinding processes, leading to poor surface integrity. In this work, CFPG experiments based on the profile characteristics of γ-TiAl blade tenon were performed and an associated undeformed chip thickness model considering grain–workpiece contact condition was established to explore the evolution of the surface integrity. Subsequently, the surface integrity was analyzed at different positions of the blade tenon in terms of surface roughness and morphology, metallographic structure, microhardness, and residual stress. Results show that the profile characteristics of blade tenon have a significant influence on machined surface integrity because of the thermomechanical effect at various detecting positions. The residual stress was established based on the undeformed chip thickness model considering the profile structure, with a prediction error of 10%–15%. The thermomechanical effect is more obvious at the bottom area, where the surface roughness, work hardening degree, and subsurface plastic deformation range are the largest, while the values at the bevel area are the smallest. Based on the undeformed chip thickness model, a residual stress finite element simulation was conducted by employing thermomechanical coupled effects. In addition, the error between the simulation and the experiment was between 10%–15%. Strain and strain rate equations were established through the relationship between material displacement and depth. The average strain and strain rate of the ground surface when a_p is 1.0 mm are 18.8% and 33.2% larger than when a_p is 0.5 mm, respectively. This study deepens the understanding of surface integrity under the influence of CFPG γ-TiAl and provides a practical reference and theoretical basis for realizing high-quality profile grinding of other complex parts.