It is essential for superalloys (e.g., Inconel 718) to obtain an anticipated surface integrity after machining, especially for safety critical areas (e.g., aerospace). As one of the main characteristics for cutting tools, the rake angle has been recognized as a key factor that can significantly influence the machining process. Although there are large research interests and outcomes in the machining of nickel-based superalloys, most of them focus on the surface integrity and macroscale temperature observation, whereas the temperature distribution in the tool rake face is not clear. Thus, it is necessary to investigate the basic role of rake angles and the tool–workpiece interaction mechanism to determine the machining condition variations and surface integrity. In the present study, both experimental and numerical methods are employed to explore the cutting force, thermal distribution, and shear angles during the process and the metallurgy characteristics of the subsurface after machining, as well as the mechanical properties. The research has emphasized the importance of rake angles on both the cutting process and machined surface integrity, and has revealed the microscale temperature distribution in the tool rake face, which is believed to have a close relationship with the tool crater wear. In addition, it is clearly presented that the surface generated with positive rake angle tools generates the minimum subsurface deformation and less strain hardening on the workpiece.

Purpose: As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.Design/methodology/approach: Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.Findings: In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.Originality/value: With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

A piezoelectric vibration sensing system (PVSS) was devised in this study and employed for the purpose of vibration sensing in machining. The system comprises three primary components, wherein the sensor is utilized for the collection and conversion of energy, subsequently transmitting it to the data acquisition card (DAC) via a low-noise cable. The crux of the entire system lies in the upper computer-based control application, which facilitates the transmission of instructions to the DAC for data acquisition and transmission. The integration of Wi-Fi data transfer capability between the DAC and the computer serves to eliminate the principal issue associated with employing the sensor as a voltage source. The sensitivity of the designed device was calibrated utilizing commercial accelerometers, while an aluminum workpiece was fabricated to conduct vibration and machining tests in order to verify the performance of the PVSS. The shaker excitation experiment yielded a peak voltage of 0.05 mV, thereby substantiating that the PVSS can more accurately discern the natural frequency of the workpiece below 5000 Hz compared to commercial accelerometers. The experiments verify that the devised PVSS can precisely measure vibrations during the milling process, and can be implemented for the purpose of detecting machining stability.

Most of the studies on cutting mechanisms and surface integrity in turning are investigated with a straight tool path (longitudinal/end face turning) while few contributions have been done in curved surface turning. This work explores the evolutions of cutting force, chip morphology and surface integrity when turning a curved surface, using fillet surface machining of AISI 304 stainless steel. The varying cutting conditions caused by the presented turning are revealed by detailed geometric analysis and employed as indicators for further discussions on cutting force, chip morphology, and machined surface integrity (including surface roughness, microhardness, microstructure, and residual stress). Apart from the difference of cutting force components in tangential, radial, and cutting speed directions along the fillet surface, wider and thinner chips are obtained from end face turning. The measured microhardness, microstructural alternation, and stress condition results comprehensively illustrate a reduction of severe plastic deformation from the outer face to the end face.

This study investigated the coupling mechanism between interlayer twist angle and projectile size on the ballistic performance of bilayer phosphorene membranes, a topic essential for designing efficient nano-protective materials, yet still poorly understood. Using coarse-grained molecular dynamic simulations, we systematically explored how twist angles (0–90°) and projectile radii (2–10 nm) jointly influence impact response for membranes with a radius equal to 48 nm. We found that the effect of twist angle becomes significant only beyond a critical projectile size (~8 nm). Below this threshold, deformation remains local and twist-independent. However, for larger projectiles, the twist angle drastically alters wave propagation and failure modes. Specifically, a 90° twist induces severe wave reflection and interference, leading to a dramatic force amplification (up to 82%) and a 28% reduction in ballistic limit velocity, making it the most susceptible configuration. These results underline the critical role of twist–boundary–wave interaction in governing impact resistance and provide practical insights for the design of phosphorene-based nano-armor systems tailored to specific impact conditions.

This study employs coarse-grained molecular dynamics simulations to investigate the synergistic coupling between interlayer twist angle (0°–90°) and projectile radius (2–10 nm) on the ballistic impact performance of bilayer phosphorene membranes (radius: 48 nm). For projectiles ≤6 nm, twist angle minimally influences impact forces, velocity attenuation, or ballistic limit velocity, as failure remains localized near the impact site. However, cone wavefront morphology evolves significantly with twist—progressing from elliptical (axial ratio 1.44 at 0°) to circular (ratio 1.0 at 90°) while rotating counterclockwise. Crucially, for projectiles ≥8 nm, twist angle critically modulates mechanical response: maximum impact force fluctuates negligibly below 60° but surges by 38% and 82% at 90° for 8 and 10 nm, respectively, triggering global membrane failure through amplified reflection and interference of cone waves. This stems from twist-dependent geometric mismatch between wavefront shape and membrane boundaries, which governs wave reflection intensity. Minimal mismatch at 90° twist maximizes force amplification, reducing ballistic limit by 28% (e.g., from 610 m/s at 0° to 440 m/s for projectiles = 10 nm). Our findings establish projectile radius as a threshold parameter that activates twist angle’s influence on impact resistance: below 6 nm, failure is local and twist-insensitive; above 8 nm, global failure emerges and is dominated by twist-mediated wave-boundary interactions, with 90° configurations exhibiting peak vulnerability. These results provide actionable guidelines for designing phosphorene-based nano-armor, emphasizing optimization of twist angle relative to anticipated projectile scales to maximize impact protection.