Key Takeaways & Executive Findings
- •• Heterogeneous aluminum/titanium alloy films exhibit up to 34.7% deeper ablation depth compared to pure aluminum alloy under femtosecond laser burst irradiation. • Increasing the number of sub-pulses with a separation time of 1 ps enhances surface temperature and ablation depth in both alloys. • Two-temperature model simulations effectively capture the ultrafast thermal dynamics and ablation behavior of heterogeneous alloys. • The findings provide a theoretical basis for efficient low-fluence laser ablation of advanced materials.
Abstract
The femtosecond laser is commonly used for high-quality micromachining of materials. However, the interaction time between the femtosecond laser and the substrate material is extremely short, making it difficult for quantitative measurements and analysis through experiments. In this work, we use a two-temperature model for simulation to study the ablation process of aluminum alloy and aluminum/titanium alloy under femtosecond laser pulse mode. The temperature changes and ablation process of both alloys under femtosecond laser burst irradiation were studied. The study found that when the separation time of sub-pulses was 1 ps, the surface temperature and ablation depth rised with the increase of sub-pulse numbers. A comparison was made between these two alloy types, and enhanced ablation was observed with the heterogeneous aluminum/titanium alloy, up to 34.7% deeper compared to aluminum alloy. Moreover, the detailed theoretical explanation was also discussed. This work provided a basis for efficient ablation of materials with low laser fluence.
1. Introduction
The rapid development of laser technology in recent years has led to its increasingly important role in the field of advanced material processing [1−4]. Femtosecond lasers are characterized by a high peak power and short pulse duration [5−8]. Compared to traditional picosecond and nanosecond lasers, femtosecond lasers have smaller thermal losses and higher cold processing efficiency [9−13]. Therefore, femtosecond lasers have been used to induce surface microstructures and femtosecond surface structuring has been a hot topic in recent years [14−20]. By consulting literature, we can know that many authors have conducted research on it [21−26]. Surface ablation is the key to femtosecond laser-induced surface microstructure formation [27, 28]. When a femtosecond laser impinges on a metal substrate, the lattice temperature rises to the vaporization temperature, which leads to surface ablation. However, the interaction time between the femtosecond laser and the material is extremely short, making it difficult to measure their changes through experimentation. Therefore, further in-depth research is needed on the dynamic process of femtosecond laser ablation of metal materials.
Presently, the two-temperature model (TTM) is commonly used to describe the interaction between a femtosecond laser and metal substrates [29−33]. Electrons absorb laser energy through photon-electron coupling, and the electron temperature rises rapidly. Then, energy is distributed to the lattice through electron-phonon coupling. Finally, the lattice temperature exceeds the vaporization temperature and results in ablation [34, 35]. AEABY et al [36] studied and analyzed the enhancement of damage threshold in bimetallic thin films, and proposed a unique analysis function to explain the distribution of damage threshold in two-layer thin films, demonstrating that multi-layer structures have a certain influence on the inter...
Loading authentic research manuscript (Pages 1–5)...
FU Shun-wei, YIN Kai, LI Xun, YANG Peng-yu, HE Yu-chun, YU Hao-nan, HUANG Yin, ARNUSCH Christopher J. (2025). Ablation enhancing on heterogeneous aluminum/titanium alloy films under femtosecond laser burst irradiation. Journal of Central South University. https://doi.org/10.1007/s11771-025-6073-5
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoTechIntel are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoTechIntel claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the main finding of this study?
The study demonstrates that heterogeneous aluminum/titanium alloy films exhibit enhanced ablation under femtosecond laser burst irradiation, achieving up to 34.7% deeper ablation depth compared to pure aluminum alloy.
How was the ablation process simulated?
The ablation process was simulated using a two-temperature model (TTM) to study the temperature changes and ablation dynamics of aluminum and aluminum/titanium alloys under femtosecond laser burst irradiation.
What is the significance of sub-pulse separation time?
With a sub-pulse separation time of 1 ps, increasing the number of sub-pulses leads to higher surface temperatures and greater ablation depths, which is crucial for optimizing laser processing parameters.
Why is the two-temperature model suitable for this research?
The two-temperature model effectively captures the ultrafast energy transfer between electrons and lattice, which is essential for understanding femtosecond laser interactions with metals where thermal equilibrium is not instantaneous.
What practical applications could this research have?
This research provides a theoretical basis for efficient ablation of materials with low laser fluence, which is beneficial for high-precision micromachining and surface structuring of advanced alloys.
Related Technical Papers & Translations
Direct Repair of the Crystal Structure and Coating Surface of Spent LiFePO4 Materials Enables Superfast Li-Ion Migration
The rapid accumulation of spent LiFePO4 (LFP) cathodes from retired lithium-ion batteries necessitates the development of effective and environmental-friendly recycling strategies. In this context, direct regeneration has emerged as a promising approach for reclaiming LFP cathode materials, offering a streamlined pathway to restore their electrochemical functionality. We report an integrated regeneration protocol that simultaneously repairs the degraded crystal structure and reconstructs the damaged carbon coating in spent LFP. The regenerated cathode material had superfast lithium-ion diffusion kinetics and a stable cathode–electrolyte interface, giving a remarkable rate capability with specific capacities of 122 mAh g−1 at 5C and 106 mAh g−1 at 10C (1C = 170 mA g−1). It also maintained capacities of 110.7 mAh g−1 (5C) and 84.1 mAh g−1 (10C) after 400 cycles. It could be used in harsh environments and could be stably cycled at subzero temperatures (−10 and −20 °C) and in solid-state electrolyte batteries. Life cycle assessment combined with economic evaluation using the EverBatt model reveals that this direct regeneration approach has high economic and environmental benefits.
Oxide Semiconductor for Advanced Memory Architectures: Atomic Layer Deposition, Key Requirement and Challenges
Oxide semiconductors (OSs), introduced by the Hosono group in the early 2000s, have evolved from display backplane materials to promising candidates for advanced memory and logic devices. The exceptionally low leakage current of OSs and compatibility with three-dimensional (3D) architectures have recently sparked renewed interest in their use in semiconductor applications. This review begins by exploring the unique material properties of OSs, which fundamentally originate from their distinct electronic band structure. Subsequently, we focus on atomic layer deposition (ALD), a core technique for growing excellent OS films, covering both basic and advanced processes compatible with 3D scaling. The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced. Furthermore, material design strategies, such as cation selection, crystallinity control, anion doping, and heterostructure engineering, are discussed. We also highlight challenges in memory applications, including contact resistance, hydrogen instability, and lack of p-type materials, and discuss the feasibility of ALD-grown OSs as potential solutions. Lastly, we provide an outlook on the role of ALD-grown OSs in memory technologies. This review bridges material fundamentals and device-level requirements, offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.
Laser powder bed fusion of biodegradable Zn-4Cu alloy: Processing, microstructure and properties
Zn's natural degradability and biocompatibility make it a promising candidate for implants, however, its mechanical properties remain insufficient for bone applications. In this study, the performance of Zn was enhanced by developing Zn-Cu alloys via laser powder bed fusion (LPBF). Optimal LPBF parameters for forming stable tracks were achieved by adjusting laser power and scanning speed. Under optimized conditions of 100 W and 100 mm/s, high-density (99.58%) Zn-Cu alloys with improved hardness (68.2HV) and yield strength (160 MPa) were achieved. These improvements are attributed to solid solution strengthening, segregation strengthening, and grain refinement. The Zn-Cu alloys also demonstrated favorable degradation behavior, with a rate of 0.16 mm/year. This degradation is primarily driven by micro-galvanic corrosion between the CuZn5 phase and Zn matrix, along with refined grains and increased grain boundary density. This work demonstrates a viable strategy for fabricating Zn-based implants with enhanced structural integrity and mechanical performance via LPBF.