The influence of W-FSAM process parameters on mechanical properties of 6061 aluminium alloyLiu, Mengmeng; Wang, Rui; Zhu, Xiaohu; Li, Songmo
doi: 10.1088/1742-6596/2951/1/012102pmid: N/A
The Wire Friction Stir Additive Manufacturing (W-FSAM) process is an emerging solid-phase friction stir-forming technology that combines friction stir welding technology with additive manufacturing. By generating heat through friction between the stirring head and the substrate, the material reaches a plastic state without reaching its melting point, effectively avoiding problems such as thermal stress, deformation, and uneven microstructure that may occur in traditional melt additive manufacturing. In addition, the characteristic of continuous feeding ensures an uninterrupted additive process, significantly improving production efficiency and ensuring an uninterrupted additive process when constructing large-sized parts. This study uses W-FSAM technology for additive moulding and investigates the effect of changing relevant parameters on the tensile strength of moulded parts.
Investigation on surface integrity of Inconel 718 in cryogenic cutting compared with dry cutting and coolant cuttingZhang, Xiaoxia; Li, Jianming; Qiao, Yang; Wang, Xiangyu
doi: 10.1088/1742-6596/2951/1/012060pmid: N/A
As a type of high-strength, thermally resistant nickel-based alloy, Inconel 718 has found extensive application in the aerospace industry. To meet the immediate demands for excellent surface integrity in engineering practices, Streamlined manufacturing process for Inconel 718 has become an unavoidable trend. The influence of various cutting parameters and cooling conditions on the surface integrity is studied through single factor cutting test. Results show that a higher cutting speed, lower feed rate, and smaller cutting depths can obtain better machined surface under the same cooling conditions. With consistent cutting parameters, cryogenic cutting can result in reduced surface roughness, lower surface residual stress, and increased microhardness, effectively enhancing surface quality. The findings demonstrate that cryogenic cutting has a favorable machining effect and a promising future, warranting greater attention.
The effect of printing parameters on the properties of PCL scaffolds prepared by pneumatic extrusion methodHuang, Lin; Zhang, Fan; Yuan, Pengwei; Yuan, Jiangshan
doi: 10.1088/1742-6596/2951/1/012093pmid: N/A
3D printing technology has been widely used in tissue engineering applications. Through this technology, tissue engineering scaffolds with complex shapes, variable pore sizes, and certain personalization can be precisely designed to provide an ideal microenvironment for cell attachment, proliferation, and differentiation. In this paper, based on the dual-stage heating nozzle structure designed by the pneumatic extrusion method, we investigated the effects of printing parameters (e.g., gas pressure level, printing speed, and second-stage heating temperature) on the characteristics of PCL scaffolds. Analysis of the results of the one-factor experiments shows that the printing parameters have a significant effect on the line width and pore size of the scaffolds, and the optimal printing parameters for the geometrical characteristics of the prepared PCL scaffolds are the gas pressure size of 0.4 MPa, the printing speed of 1.25 mm/s, and the second-stage heating temperature of 90°C. The results of the single-factor experiments show that the printing parameters have a significant effect on the line width and pore size of the scaffolds. These results lay the foundation for further optimizing the printing conditions for the preparation of PCL scaffolds based on pneumatic extrusion.
Research on quantitative characterization method of tensile and compressive stress based on incremental magnetic permeability principleLi, Hengtao; Liu, Yan; Yao, Huan; Wang, Xianxian
doi: 10.1088/1742-6596/2951/1/012087pmid: N/A
In this study, non-destructive quantitative characterization of stresses in low, medium, and high carbon steels was carried out based on the principle of incremental permeability (IP) detection. First, a special fixture was designed and constructed to perform calibration experiments on a single flat plate tensile specimen to obtain the incremental magnetic permeability signals at different compressive and tensile stress levels. Subsequently, the relationship between the magnetic parameter and the stress characterization was analyzed. Finally, a network model was established to realize the quantitative characterization of tensile and compressive stresses in low, medium, and high carbon steels using the magnetic parameter. The results show that the incremental magnetic permeability detection technique can effectively predict the carbon steel stresses non-destructively and quantitatively, and the average relative errors of the model predicted low, medium, and high carbon steel stresses are 1.60 MPa, 1.28 MPa, and 2.54 MPa, respectively. The methods and conclusions proposed in this study provide important references for non-destructive testing of carbon steel stresses.
Simulation analysis of nonlinear consolidation in soft soil based on large-scale consolidation permeability testsYue, Changxi; Pan, Wei; Cao, Yonghua; Ye, Guoliang; Yu, Changyi
doi: 10.1088/1742-6596/2951/1/012085pmid: N/A
To mitigate the influence of test size on the nonlinear compression and permeability characteristics of soft soils, this study utilized a custom-made large scale consolidation-permeation apparatus to conduct indoor experiments. The relationship between the permeability coefficient and consolidation pressure of soft clay, with the preconsolidation stress as the critical point, was obtained. A nonlinear permeability model based on growth curves was established, with relevant fitting coefficients exceeding 0.99. Finally, through the secondary development of a finite element software subroutine, the nonlinear consolidation calculations of the soil were implemented and compared with experimental results, thereby validating the reliability of the model.
Design and performance of trapezoidal honeycomb absorbing structure based on FDMWang, Run; Han, Yafeng; Lu, Jiping; Gong, Chenglong; Wang, Haoren; Xia, Yuhan; Xiang, Zezhi
doi: 10.1088/1742-6596/2951/1/012006pmid: N/A
The increasing prevalence of electronic devices and the rapid evolution of communication technologies underscore the critical need for effective management of electromagnetic interference and assurance of electromagnetic compatibility. This study presents an innovative trapezoidal honeycomb absorber structure, optimized to enhance the absorption of electromagnetic waves across a broad spectrum. By leveraging Fused Deposition Modeling (FDM) 3D printing technology, we have fabricated a short-cut carbon fiber composite material that exhibits superior electromagnetic and mechanical properties. Our research specifically focused on optimizing the honeycomb sidewall inclination angle to maximize absorption performance. We discovered that a 15° angle configuration yielded the broadest effective absorption bandwidth and the highest absorption efficiency. The structure demonstrated a significant -10 dB absorption bandwidth of 9.95 GHz within the 2-18 GHz range, underscoring its potential for managing a wide spectrum of electromagnetic waves. Furthermore, we explored the absorber’s performance under various angles of incidence, confirming its robustness across a broad range. These findings significantly advance the development of electromagnetic wave absorption materials, positioning the trapezoidal honeycomb structure as a key technology for future electromagnetic wave shielding applications.
Research on thermal insulation technology of aerospace cryogenic propellant tankYu, Bin; Huang, Cheng; Wang, Tian; Zhao, Jipeng; Ma, Tianju; Gu, Sendong; Chang, Xin; Wu, Zihao; Chen, Linfeng
doi: 10.1088/1742-6596/2951/1/012063pmid: N/A
In this paper, the thermal insulation layer, thermal insulation support, and metal interface of the cryogenic tank are taken as the research objects, and the structural design, heat transfer mechanism analysis, heat transfer calculation model establishment, heat transfer calculation and result analysis, and temperature field numerical simulation of the cryogenic tank are studied. The heat transfer mechanism of Spray-On Foam Insulation (SOFI)/Varied Density Multi-Layer Insulation (VD-MLI) in the ground stage and space stage is analyzed. In the ground stage, SOFI heat conduction and radiation heat transfer between adjacent radiation layers in VD-MLI, gas heat conduction between adjacent radiation layers, and solid heat conduction between adjacent radiation layers were considered in terms of insulation layer design. In the space stage, SOFI heat conduction and radiation heat transfer between adjacent radiation layers in VD-MLI, residual gas heat conduction between adjacent radiation layers, and solid heat conduction between adjacent radiation layers were considered in terms of insulation layer design. Based on the heat transfer process of SOFI/VD-MLI in the ground stage and space stage, the heat transfer calculation model of SOFI/VD-MLI in the ground stage and space stage is established. According to the evaporation rate requirements of aerospace cryogenic propellant, the thermal insulation layer, thermal insulation support, and metal interface were optimized, which effectively controlled the heat flux density (HFD) and heat leakage (HL) of the cryogenic tank and ensured the evaporation rate index of cryogenic propellant and Zero Boil Off (ZBO) storage.
Scheme design and structural safety analysis of lifting net cageWang, Shaomin; Ma, Zhenhua; Yang, Xieqiu; Bai, Zemin; Qiu, Yu
doi: 10.1088/1742-6596/2951/1/012002pmid: N/A
Deep-water cage culture can better simulate the natural growth environment of fish, improve the culture environment, and improve the yield and quality of cultured varieties. A lifting cage is a new type of fishery culture equipment, which has the advantages that ordinary deep-sea cages do not have: lifting can be realized in the case of heavy waves, wave load can be reduced, and structural safety can be improved. In this paper, according to the needs of deep-sea aquaculture, a lifting cage scheme is designed, the structural strength and stability of the cage structure under extremely typical working conditions are checked by ANSYS, and the stress concentration parts are optimized. The results show that the lifting cage platform designed in this paper has the characteristics of a simple structure and high safety factor, which provides a reference for structural design and safety evaluation of deep-sea lifting cages.
Study on forming and controlling technology of iron oxide for low carton free cutting steel rodWang, Liyin; Li, Huicheng; Ou, Junfei; Yang, Chengwei; Zhu, Fei; Xie, Changsheng
doi: 10.1088/1742-6596/2951/1/012013pmid: N/A
This paper introduces the process and mechanism of iron oxide in the rolling process of low carbon and sulfur-bearing free-cutting steel rods, and studies the influencing factors of oxide forming thickness and structure control by analyzing the forming characteristics of various oxides. To control the wire oxidation scale, which is conducive to pickling and drawing in downstream processing, we optimize and control the rolling process, by reducing the spinning or curling temperature to 900-950°C, reducing the amount of oxide sheet, controlling the thickness of the oxide sheet, and improve the overall quality of oxide sheet. The oxidation thickness of low carbon sulfur-free cutting steel wire rods can be controlled at 20-28 um.
Study on the erosion-corrosion behavior of copper-nickel alloys in high temperature and high humidity marine environmentWang, Kun; Tian, Xuefeng; Liu, Xu; Wang, Gui; Deng, Jianhua
doi: 10.1088/1742-6596/2951/1/012103pmid: N/A
This paper focuses on the study of B10 copper-nickel alloy, utilizing a self-designed tubular flow erosion device to simulate the seawater environment. Various testing techniques, including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curve measurements, and X-ray energy dispersive spectroscopy (EDS) analysis, were employed to investigate the erosion-corrosion behavior of B10 alloy in the South China Sea seawater. Combined with the observation of corrosion morphology and compositional analysis, the influence laws of different time durations, temperatures, and flow velocities on the initial erosion-corrosion of B10 alloy were discussed. The results indicated that during erosion tests conducted in dynamic seawater with a flow velocity of 3 m/s and a temperature of 40°C for varying durations (30 minutes, 1 hour, 2 hours, and 4 hours), the highest corrosion potential was observed at 2 hours, with an oxygen (O) elemental weight percentage of 16.34%. As the erosion time increased, the oxide layers on the B10 surface gradually became denser. When erosion tests were conducted at a flow velocity of 3 m/s and an erosion time of 2 hours, but with varying temperatures (30°C, 40°C, and 50°C), the results showed that at 40°C, the erosion traces on the B10 surface were pronounced, indicating severe corrosion. At 50°C, the oxide layers on the material surface were relatively dense, accompanied by a higher number of rust blisters. The O elemental content was the lowest. In tests conducted at a temperature of 40°C, an erosion time of 2 hours, but with varying flow velocities (1 m/s, 2 m/s, 3 m/s, and 4 m/s), it was found that at a flow velocity of 3 m/s, the erosion traces were most evident, with large and numerous corrosion pits. However, at a flow velocity of 4 m/s, the oxide layers on the material surface were denser. The corrosion traces were gradually covered by a passivation film, rendering the corrosion pits less apparent.