Optics and Laser Technology最新文献_第8页

Terahertz smart devices based on phase change material VO2 and metamaterial graphene that combine thermally adjustable absorption and selective transmission 基于相变材料 VO2 和超材料石墨烯的太赫兹智能设备，兼具热调节吸收和选择性传输功能

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111928

Wenqiang Lu , Weiming Zhang , Qianju Song , Zao Yi , Shubo Cheng , Bin Tang , Qingdong Zeng , Pinghui Wu , Sohail Ahmad

In this paper, a classical three-layer structure of proportionate terahertz intelligent device composed of vanadium dioxide and graphene is simulated and designed. The proportionate setting of this intelligent device allows for better control over the size of surface microstructures, thereby enhancing the utilization of materials during the production process. At a temperature of T = 345 K, the device exhibits perfect absorption efficiency of greater than or equal to 90 % in the frequency range of 2.46 THz to 6.85 THz (4.39 THz), spanning almost half of the terahertz band. At a temperature of T = 323 K, the device achieves absorption of over 77.3 % in the frequency range of 3.04 THz to 5.64 THz, with average transmittance rates of 69.61 % and 69.79 % in the frequency ranges of 0.01 THz to 2.32 THz and 6.82 THz to 10.00 THz, respectively. We use vanadium dioxide as the bottom layer to avoid the effect of traditional metal substrates that prevent electromagnetic waves from transmitting and limit the conversion of terahertz device performance. Temperature modulation enables control over absorption and transmission. We first explain the results based on the crystal structure within VO₂ and then analyze the surface electric field of the device at two temperatures using surface plasmons (SPs). By adjusting the structural parameters of the absorber and applying an external bias voltage, the Fermi energy of graphene can be altered, demonstrating the device’s physical coherence, manufacturing tolerance, and dynamic tuning capability. We investigate the influence of different incident angles of external electromagnetic waves on the device performance, showing that it maintains excellent performance over a wide range of angles, which is crucial for practical applications. Finally, we examined the implications of employing the Drude model to characterize silicon dioxide in the terahertz range and its potential impact on device performance. This holds significant implications for communication, detection, sensing, imaging, and provides insights for future terahertz device development.

本文模拟并设计了一种由二氧化钒和石墨烯组成的经典三层结构比例太赫兹智能装置。这种智能器件的比例设置可以更好地控制表面微结构的尺寸，从而在生产过程中提高材料的利用率。在温度为 T = 345 K 时，该装置在 2.46 THz 至 6.85 THz（4.39 THz）的频率范围内表现出大于或等于 90 % 的完美吸收效率，几乎跨越了太赫兹波段的一半。在温度 T = 323 K 时，该器件在 3.04 THz 至 5.64 THz 频率范围内的吸收率超过 77.3%，在 0.01 THz 至 2.32 THz 和 6.82 THz 至 10.00 THz 频率范围内的平均透过率分别为 69.61% 和 69.79%。我们使用二氧化钒作为底层，以避免传统金属基底阻碍电磁波传输和限制太赫兹器件性能转换的影响。温度调制实现了对吸收和传输的控制。我们首先解释了基于 VO2 内部晶体结构的结果，然后利用表面等离子体（SP）分析了该器件在两个温度下的表面电场。通过调整吸收器的结构参数和施加外部偏置电压，可以改变石墨烯的费米能，从而证明了该器件的物理相干性、制造耐受性和动态调节能力。我们研究了外部电磁波不同入射角度对该器件性能的影响，结果表明它能在很大的角度范围内保持优异的性能，这对实际应用至关重要。最后，我们研究了在太赫兹范围内采用德鲁德模型表征二氧化硅的意义及其对器件性能的潜在影响。这对通信、探测、传感和成像具有重要意义，并为未来太赫兹器件的开发提供了启示。

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引用次数: 0

Bandwidth enhancement of InP/InGaAs waveguide uni-traveling carrier photodetectors for over 100 GHz bandwidth using impedance lines 利用阻抗线增强 InP/InGaAs 波导单游程载流子光电探测器的带宽，使其带宽超过 100 GHz

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111942

Han Ye , Qin Han , Shuai Wang , Liyan Geng , Yimiao Chu , Yu Zheng

Uni-traveling carrier photodetectors are highly competitive for the next generation over 200Gbaud/λ ultra-fast data fiber-optic communication systems. An impedance line is integrated to the photodetector for a 100 % bandwidth enhancement within a wide range of device areas. A modified equivalent circuit model is proposed to explain the resistance matching and inductive peaking effect of the impedance line. The fabricated chip exhibits a high bandwidth of 140 GHz with an ultra-low dark current of 0.078nA for the 50 μm² photodetector, and an external responsivity of 0.262A/W.

单程载波光电探测器在下一代超过 200Gbaud/λ 的超高速数据光纤通信系统中极具竞争力。光电探测器集成了阻抗线，可在大范围器件区域内提高 100% 的带宽。为解释阻抗线的电阻匹配和电感峰值效应，提出了一个改进的等效电路模型。制造出的芯片具有 140 GHz 的高带宽，50 μm2 光电探测器的超低暗电流为 0.078nA，外部响应率为 0.262A/W。

引用次数: 0

Process parameter optimization of Fe-based coating on ductile iron using laser cladding with grey related analysis 利用激光熔覆优化球墨铸铁铁基涂层的工艺参数及灰色关联分析

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111906

Yiqi Wang, Tianbiao Yu, Yingying Zhang, Jiayu Sun, Zhengyu Sun

Owing to the laser cladding process for substantial damage in dust cast iron, this study systematically investigated the Fe-based single-track laser modification process for ductile cast iron, aiming to reduce the damage to ductile iron during laser cladding (LC). The three parameters, laser power (P), scanning speed (V) and powder feeding rate (F) were optimized by employing the Taguchi-grey correlation method. A Taguchi-designed orthogonal experiment was conducted focused on cladding width, cladding height, and dilution rate as the response targets. Insights into the impact of process parameters on geometric characteristics were provided by contour plots, surface plots, and Signal-to-Noise Ratio (S/N) analysis. With the grey relational theory, the three response targets were transformed into a single Grey Relational Grade (GRG) value, quantifying the optimization for maximum cladding width (W), cladding height (H), and appropriate dilution rate (D). Additionally, the results indicated the improvements in the three response targets, discussing the optimized cladding layer’s advantage in morphology and microstructure compared to other layers. This study provides the theoretical feasibility of laser cladded Fe-based powders for laser cladded cast iron.

由于激光熔覆工艺会对粉尘铸铁造成严重破坏，本研究系统地研究了球墨铸铁的铁基单轨激光改性工艺，旨在减少激光熔覆（LC）过程中对球墨铸铁的损伤。采用田口-灰色关联法对激光功率（P）、扫描速度（V）和送粉率（F）这三个参数进行了优化。以包层宽度、包层高度和稀释率为响应目标，进行了田口设计正交实验。通过等高线图、表面图和信噪比（S/N）分析，深入了解了工艺参数对几何特性的影响。利用灰色关系理论，三个响应目标被转化为单一的灰色关系等级（GRG）值，量化了最大包层宽度（W）、包层高度（H）和适当稀释率（D）的优化。此外，研究结果还显示了三个响应目标的改善情况，讨论了与其他层相比，优化后的包层在形态和微观结构方面的优势。这项研究为激光熔覆铸铁提供了铁基粉末的理论可行性。

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引用次数: 0

Enhancing free-space optical communication networks using Generalized Low Density Parity Check codes 利用广义低密度奇偶校验码增强自由空间光通信网络

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111862

Albashir A. Youssef , Sherif I. Elsanadily

Free Space Optical (FSO) communications gained impressive adoption in the research society. The high data rate, unlicensed frequency bandwidth, low cost, and immense security of FSO systems influence this much attention. Due to these benefits, FSO can fit into various communication system applications. Atmospheric turbulence (AT) is the main channel impairment faced by the FSO links, which affects their efficiency. Atmospheric turbulence existed due to haphazard variations of the air refractive index within communication duration. Several mathematical models are used to characterize the AT. The Log-Normal (LN) model exhibits weak and moderate turbulence, while for strong turbulence, the Gamma–Gamma (G-G) model is employed. The effects of geometric losses, weather attenuation, and misalignment errors are accounted for by maintaining the later models. So, the best candidate solution for enhancing FSO communication link performance is channel coding algorithms like Generalized Low-Density Parity Check (GLDPC) codes. This paper proposes a new FSO system that utilizes two novel GLDPC decoders to enhance the performance of the FSO communication channels and reduce its impairments. To demonstrate the effect of the proposed system on preserving cutting-edge GLDPC coding algorithms, all factors influencing FSO communications are also assessed. To evaluate the bit error rate (BER) of the proposed system combined with novel GLDPC decoders, the number of consumed iterations, dissipated decoding time, extracted throughput, and convergence of decoders are maintained. The findings demonstrated that, in the case of FSO communication channels, the new GLDPC decoding algorithms in the proposed system performed better than the current ones across all comparison points used in this investigation.

自由空间光学（FSO）通信在研究领域获得了令人瞩目的应用。FSO 系统的高数据传输率、非授权频率带宽、低成本和巨大的安全性使其备受关注。由于这些优点，FSO 可以应用于各种通信系统。大气湍流（AT）是 FSO 链路面临的主要信道障碍，会影响其效率。大气湍流的存在是由于通信持续时间内空气折射率的杂乱变化。有几种数学模型可用于描述 AT 的特征。对数-正态（LN）模型适用于弱湍流和中等湍流，而对于强湍流，则采用伽马-伽马（G-G）模型。几何损耗、天气衰减和不对齐误差的影响通过保持后面的模型得到了考虑。因此，提高 FSO 通信链路性能的最佳候选解决方案是通用低密度奇偶校验（GLDPC）码等信道编码算法。本文提出了一种新的 FSO 系统，利用两个新型 GLDPC 解码器来提高 FSO 通信信道的性能并减少其损伤。为了证明所提系统对保留尖端 GLDPC 编码算法的效果，还对影响 FSO 通信的所有因素进行了评估。为了评估与新型 GLDPC 解码器相结合的拟议系统的误码率 (BER)，还保留了迭代次数、耗散的解码时间、提取的吞吐量和解码器的收敛性。研究结果表明，在 FSO 通信信道的情况下，拟议系统中的新型 GLDPC 解码算法在所有比较点上的表现都优于当前的算法。

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引用次数: 0

High efficiency broadband parametric amplification assisted by second harmonic generation 利用二次谐波生成技术辅助高效宽带参量放大

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111887

Zhihao Wang , Lu Xu , Shuangxi Peng , Feilong Hu , Dong Zhao , Zuofei Hong , Qingbin Zhang , Peixiang Lu

In typical scenarios, quadratic nonlinear processes such as second harmonic generation (SHG) and sum frequency generation (SFG) that accompany optical parametric amplification (OPA) are often considered unfavorable parasitic effects. These effects can lead to a reduction in energy conversion efficiency during OPA. In this study, we demonstrate an approach to enhance OPA efficiency by eliminating the signal pulse through SHG in a simple collinear geometry while maintaining a broadband output using a femtosecond pump laser. The complete setup features a three-stage OPA system, with the final stage employing a hybrid OPA-SHG process that effectively suppresses back conversion, achieving up to 60.8 % pump depletion and 26.2 % pump-to-idler energy conversion, resulting in an idler energy of 0.97 mJ. By harnessing the capabilities of a broadband femtosecond pump and Type-I phase matching to enhance phase-matched bandwidth, we generated a 1.85-μm idler pulse with a near-transform-limited (TL) duration of 33.5 fs through compression in a silicon window. Furthermore, we maintained excellent beam quality and output power stability, with only 0.23 % root mean square (RMS) fluctuations over the course of one hour. This mid-IR laser source, operating at the millijoule (mJ) level and characterized by its high beam quality, is exceptionally well-suited for advancing attosecond and strong-field research.

在典型情况下，伴随光参量放大（OPA）产生的二次谐波生成（SHG）和和频生成（SFG）等二次非线性过程通常被认为是不利的寄生效应。这些效应会导致 OPA 期间的能量转换效率降低。在本研究中，我们展示了一种提高 OPA 效率的方法，即在简单的准直几何结构中通过 SHG 消除信号脉冲，同时使用飞秒泵浦激光器保持宽带输出。整套装置采用三级 OPA 系统，最后一级采用 OPA-SHG 混合工艺，可有效抑制反向转换，实现高达 60.8% 的泵浦耗尽和 26.2% 的泵浦到惰极能量转换，从而产生 0.97 mJ 的惰极能量。通过利用宽带飞秒泵浦和 I 型相位匹配的能力来增强相位匹配带宽，我们在硅窗口中通过压缩产生了 1.85μm 的惰极脉冲，其持续时间接近 33.5 fs。此外，我们还保持了出色的光束质量和输出功率稳定性，一小时内的均方根波动仅为 0.23%。这种中红外激光源工作在毫焦耳（mJ）级别，具有光束质量高的特点，非常适合推进阿秒和强场研究。

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引用次数: 0

Magnetic-assisted laser shock peening of 7075-T6 aluminum alloy 7075-T6 铝合金的磁辅助激光冲击强化

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111923

Binghan Huang, Longjie Xu, Chao Tang, Yang Yang, Junhao Wu, Yu Zhang, Yixuan Ye, Tao Huang, Chang Ye, Han Ding

In this study, an innovative process, magnetic–assisted laser shock peening (MA-LSP), was used to strengthen 7075-T6 aluminum alloy. In the MA-LSP process, the target sample is placed in a magnetic field during laser shock peening. The effects of MA-LSP treatment and conventional LSP treatment were compared to explore the influence of magnetic field on the peening effect. The results showed that the surface peening indentations were deeper after MA-LSP treatment than after conventional LSP, indicating a greater impact energy received. After MA-LSP, the surface grains were more obviously refined, the surface hardness was significantly improved, and a deeper hardened layer was produced. In-depth residual stress tests indicated a greater surface compressive residual stress of the sample after MA-LSP, and the compressive residual stress layer of the sample was also deeper. In addition, the sample exhibited greater strength following MA-LSP. It is believed that both magnetoplasticity and the constraining effect exerted by the magnetic field on plasma expansion play a role in enhancing the peening effects.

本研究采用了一种创新工艺--磁辅助激光冲击强化（MA-LSP）来强化 7075-T6 铝合金。在 MA-LSP 工艺中，目标样品在激光冲击强化过程中被置于磁场中。比较了 MA-LSP 处理和传统 LSP 处理的效果，以探索磁场对强化效果的影响。结果表明，MA-LSP 处理后的表面强化压痕比传统 LSP 处理后的压痕更深，表明接收到的冲击能量更大。经过 MA-LSP 处理后，表面晶粒细化更明显，表面硬度显著提高，并产生了更深的硬化层。深度残余应力测试表明，MA-LSP 后试样的表面压缩残余应力更大，试样的压缩残余应力层也更深。此外，试样在 MA-LSP 之后表现出更高的强度。我们认为，磁塑性和磁场对等离子体膨胀产生的约束效应在增强强化效果方面都发挥了作用。

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引用次数: 0

MSDA-HLGCformer-based context-aware fusion network for underwater organism detection 基于 MSDA-HLGCformer 的水下生物探测上下文感知融合网络

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111957

Heng Wu , Yisi Liu , Chunhua He , Shaojuan Luo

Underwater organism detection is crucial for marine ecology research and resource management. However, underwater images often suffer from issues like blurring, noise, and color distortion, making it challenging to distinguish targets from complex backgrounds. Existing detection methods struggle to separate targets in such conditions. To address these problems, we propose a Cross-Context Fusion Transformer YOLO network (CCFT-YOLO) for underwater organism detection. Specifically, we propose an MSDA-HLGCformer backbone network that captures and integrates local features at different depths and distances through the Multi-Scale Dilated Attention (MSDA) block at the low level, while at the high level, a hierarchical local–global context former (HLGCformer) is developed to contextualize the information at each scale, allowing the model to focus on the global context of the underwater environment. A context-aware cross-level fusion module (CACLFM) is designed to balance the retention of salient target and background texture information by integrating local and global information. Quantitative and qualitative experimental results show that CCFT-YOLO is competitive and robust in underwater organism detection compared to other state-of-the-art detectors.

水下生物探测对于海洋生态学研究和资源管理至关重要。然而，水下图像往往存在模糊、噪声和色彩失真等问题，使得从复杂背景中区分目标变得十分困难。现有的检测方法很难在这种情况下分离目标。为了解决这些问题，我们提出了一种用于水下生物检测的跨语境融合变换 YOLO 网络（CCFT-YOLO）。具体来说，我们提出了一个 MSDA-HLGCformer 骨干网络，该网络在低层次上通过多尺度稀释注意力（MSDA）模块捕捉并整合不同深度和距离的局部特征，而在高层次上，则开发了一个分层局部-全局上下文前置器（HLGCformer），将每个尺度上的信息上下文化，使模型能够关注水下环境的全局上下文。设计了一个情境感知跨层融合模块（CACLFM），通过整合局部和全局信息，平衡保留突出的目标和背景纹理信息。定量和定性实验结果表明，与其他最先进的探测器相比，CCFT-YOLO 在水下生物检测方面具有竞争力和鲁棒性。

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引用次数: 0

High-accuracy 6-D pose measurement method for 3C thin parts in robotic assembly by monocular vision 利用单目视觉对机器人装配中的 3C 薄部件进行高精度 6-D 姿态测量的方法

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-10 DOI: 10.1016/j.optlastec.2024.111937

Bin Wang, Jiwen Zhang, Song Wang, Dan Wu

The 6-D pose measurement of the 3C thin parts is essential for alignment process in robotic assembly. Due to the thin thickness, features from two surfaces are coupled together and difficult to distinguish in the image, causing the decrease in the accuracy of the pose measurement. In this study, a 6-D pose measurement method based on the monocular vision is proposed. An algorithm named dual-surface reprojection contour error optimization (DSRCEO) is proposed to simultaneously optimize the features from both two surfaces to improve the accuracy of pose measurement. In the DSRCEO, the computational domain and the image domain are constructed, and then an error index of DSRCE is derived by comprehensive consideration of the two domains to evaluate the quality of the current pose estimation. By minimizing the DSRCE, the initial estimation of the 6-D pose is iteratively optimized to continuously improve the measurement accuracy. The framework of the DSRCEO is available for the thin parts with various shapes, and specific algorithm implementations for the two most common shapes (trimmed circle and polygon) are derived. Finally, the accuracy and applicability of the proposed algorithm are verified through both sufficient simulation and experiments.

3C 薄部件的 6-D 姿态测量对于机器人装配中的对准过程至关重要。由于厚度较薄，两个表面的特征耦合在一起，在图像中难以分辨，导致姿态测量的精度降低。本研究提出了一种基于单目视觉的 6-D 姿态测量方法。研究提出了一种名为 "双表面轮廓投影误差优化（DSRCEO）"的算法，通过同时优化两个表面的特征来提高姿态测量的精度。在 DSRCEO 中，首先构建计算域和图像域，然后通过综合考虑两个域得出 DSRCE 误差指数，以评估当前姿态估计的质量。通过最小化 DSRCE，对 6-D 姿态的初始估计进行迭代优化，从而不断提高测量精度。DSRCEO 框架适用于各种形状的薄部件，并推导出两种最常见形状（修剪圆和多边形）的具体算法实现。最后，通过充分的模拟和实验验证了所提算法的准确性和适用性。

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引用次数: 0

A short-range quasi-distributed strain and temperature sensing system utilizing a standard telecom laser diode 利用标准电信激光二极管的短程准分布式应变和温度传感系统

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-09 DOI: 10.1016/j.optlastec.2024.111919

Jure Javornik, Denis Đonlagić

This article presents a short-range fiber-optic quasi-distributed sensing device suitable for strain and temperature measurement. The sensing assembly consists of an fs laser inscribed reference mirror and a sensing array of equidistantly positioned mirrors. Utilization of the reference mirror and proper sensor geometry selection provides the possibility for a high-resolution spectral interrogation of the sensing array while relying on an ordinary, cost-effective distributed feedback (DFB) telecom laser diode. Beside the telecom DFB diode, the entire interrogation system includes only an additional detector, optical coupler, analog interface and a microcontroller. Measurement resolution better than 1 µε was demonstrated experimentally at a sampling rate exceeding 65 samples per second, while utilizing a sensing device with a typical length of 50 mm and spatial resolution of approximately 2 mm. To demonstrate the application potential of the proposed measuring device, a few different packages and sensor configurations were demonstrated and tested, including a system for tactile sensing applications and a short-range quasi-distributed temperature measurement probe.

本文介绍了一种适用于应变和温度测量的短程光纤准分布式传感装置。传感组件包括一个 fs 激光刻划参考镜和一个由等距定位镜组成的传感阵列。利用参考镜和适当的传感几何形状选择，可以对传感阵列进行高分辨率光谱检测，同时依靠一个普通的、具有成本效益的分布式反馈（DFB）电信激光二极管。除了电信 DFB 二极管外，整个询问系统只包括一个额外的探测器、光耦合器、模拟接口和微控制器。实验证明，利用典型长度为 50 毫米、空间分辨率约为 2 毫米的传感设备，在采样率超过 65 个样本/秒的情况下，测量分辨率优于 1 µε。为了证明拟议测量设备的应用潜力，对一些不同的封装和传感器配置进行了演示和测试，包括一个触觉传感应用系统和一个短距离准分布式温度测量探头。

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引用次数: 0

Laser transmission joining of plasma treated polypropylene to stainless steel: Interfacial microstructure and mechanical properties 等离子处理聚丙烯与不锈钢的激光透射连接：界面微观结构和机械性能

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-10-09 DOI: 10.1016/j.optlastec.2024.111930

Yinjiao He , Jin Yang , J.P. Oliveira , Ruijun Wang , Ruijie Hao , Yixuan Zhao , Junhua Shao , Yiyu Xu , Jianguang Zhai

Hybrid joints between polypropylene (PP) and 316L stainless steel (316L) have been widely used in various industrial fields, such as automotive, medical equipment, and electronic devices. The difficulty in the joining PP to 316L is that the former is a non-polar polymer, which makes it difficult to initiate a chemical reaction at the interface between the two materials. This ultimately results in a joint with low strength. Additionally, the melting point and thermal conductivity of the two materials differ significantly, so it is necessary to properly control the laser heat input. To tackle this challenge, the PP surface was pre-treated by plasma and then joined to 316L by laser transmission welding technology. The polar groups introduced by the plasma-treated PP form new chemical bonds with the metal and metal oxides of 316L, resulting in high quality dissimilar joints. The macromorphology and microstructure of the interface were investigated comparatively with different scanning speeds. The results showed that the optimal scanning speed was 10 mm/s at a laser power of 60 W and a defocusing distance of 0 mm, resulting in a maximum lap shear force of 149.18 N and an optimal macroscopic morphology. Furthermore, the correlation between the change in weld morphology and the mechanical properties was investigated, and the morphological and chemical bonding of the fracture were analyzed to elucidate the joint connection mechanisms.

聚丙烯（PP）和 316L 不锈钢（316L）之间的混合接头已广泛应用于汽车、医疗设备和电子设备等多个工业领域。聚丙烯与 316L 连接的难点在于，前者是一种非极性聚合物，因此很难在两种材料的界面上引发化学反应。这最终导致连接强度较低。此外，这两种材料的熔点和导热性差异很大，因此有必要适当控制激光热输入。为了解决这一难题，我们先用等离子体对 PP 表面进行预处理，然后用激光透射焊接技术将其与 316L 连接起来。经过等离子处理的聚丙烯所引入的极性基团与 316L 的金属和金属氧化物形成了新的化学键，从而形成了高质量的异种接头。比较研究了不同扫描速度下界面的宏观形态和微观结构。结果表明，在激光功率为 60 W、散焦距离为 0 mm 时，最佳扫描速度为 10 mm/s，可获得 149.18 N 的最大搭接剪切力和最佳宏观形态。此外，还研究了焊缝形态变化与力学性能之间的相关性，并分析了断口的形态和化学结合，以阐明接头连接机制。

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引用次数: 0