Powder Technology最新文献_第9页

Mechanism of deglomeration for waste printed circuit boards (WPCBs) via grinding activation 废印刷电路板磨矿活化脱杂机理研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-28 DOI: 10.1016/j.powtec.2026.122189

Tao Long , Yuanxiang Zhao , Wei Yang , Sha Deng , Chao Yang , Jinrong Ju

The rapid obsolescence of electronics has led to a global surge in electronic waste. A major recycling challenge is the severe agglomeration of comminuted waste printed circuit board (WPCB) powders, driven by hydrophobic interactions, which significantly hinders metal recovery. This study employed grinding activation as a pretreatment to enhance the dispersion of WPCB powders in water, thereby improving downstream gravity separation. The article compares the effects of grinding with those of stirring dispersion and chemical (ethanol) dispersion, and analyzes their mechanisms. Contact angle measurements confirmed the inherent surface hydrophobicity causing aggregation. Comparative analysis demonstrated that optimal ball milling for 45 s was the most effective method for deagglomeration, outperforming alternatives like ethanol-assisted dispersion. This pretreatment yielded a copper concentrate grade of 26.92% with a high recovery rate of 93.22%, Compared with ethanol-assisted stirring dispersion, the grade and recovery rate increased by 2.89% and 12.94%, respectively. Mechanistic analysis revealed that the performance enhancement stemmed from improved particle liberation, a morphological change of metals to spherical shapes, and the removal of hydrophobic resin coatings. These findings establish the integration of grinding activation with gravity separation as an efficient and environmentally sound strategy for metal recovery from WPCBs.

电子产品的迅速过时导致全球电子垃圾激增。一个主要的回收挑战是由疏水相互作用驱动的废弃印刷电路板（WPCB）粉末的严重团聚，这严重阻碍了金属的回收。本研究采用磨矿活化作为预处理，增强WPCB粉体在水中的分散，从而改善下游重选。比较了粉碎与搅拌分散和化学（乙醇）分散的效果，并分析了其作用机理。接触角测量证实了引起聚集的固有表面疏水性。对比分析表明，最佳球磨45 s是最有效的解团聚方法，优于乙醇辅助分散等替代方法。预处理后的铜精矿品位为26.92%，回收率为93.22%，与乙醇辅助搅拌分散相比，铜精矿品位和回收率分别提高了2.89%和12.94%。力学分析表明，性能的增强源于颗粒的解放、金属形态的球形变化以及疏水性树脂涂层的去除。这些研究结果表明，将磨矿活化与重力分离相结合，是一种有效且环保的从wpcb中回收金属的策略。

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引用次数: 0

Study on enhanced flotation of fine-grained cassiterite using sodium monododecyl phosphate as a novel hydrophobic modifier and its mechanism 新型疏水改性剂单十二烷基磷酸钠强化细粒锡石浮选及其机理研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-24 DOI: 10.1016/j.powtec.2026.122171

Renjie Yang , Xun Wang , Xian Xie , Xiong Tong , Ruiqi Xie

Efficient flotation of fine-grained cassiterite is a universally recognized challenge in the tin mineral processing industry. Currently, the traditional flotation process faces issues in its recovery, including low tin recovery rate, high gangue entrainment, and excessive reagent consumption. For the first time, this study employed sodium monododecyl phosphate (SMP) as a hydrophobic modifier to pretreat fine-grained cassiterite, realizing the mineral's selective hydrophobic agglomeration and thereby enhancing its flotation recovery with the traditional collector salicylhydroxamic acid (SHA). Flotation experimental results showed that SHA performed poorly in floating the −23 μm cassiterite fraction, with a recovery of only 14.69% under optimal conditions. In contrast, pretreating fine-grained cassiterite with SMP (stirring speed: 700 rpm, pH: 9, SMP concentration: 130 mg/L, stirring time: 5 min) increased its recovery to 80.39% (an enhancement of 65.70%) under otherwise unchanged flotation conditions. Furthermore, artificial mixed ore flotation experiments confirmed that SMP exerted a favorable selective hydrophobic agglomeration effect on cassiterite, enabling the selective enhanced recovery of cassiterite in cassiterite-quartz mixed systems. Additionally, the mechanism underlying SMP-induced flotation enhancement was clarified using a series of surface analysis techniques. SMP forms chemical bonds with Sn atoms on the cassiterite surface using its phosphate groups as anchoring sites, ultimately generating stable Sn-O-P-O-Sn five-membered cyclic chelates adsorbed on the cassiterite surface. This enhances inter-particle hydrophobic interactions, promotes cassiterite agglomeration, increases the mineral's apparent particle size, and thus strengthens flotation recovery. This study provides a novel hydrophobic modifier and a feasible strategy for the efficient flotation of fine-grained cassiterite.

细粒锡石的高效浮选是锡矿加工行业公认的难题。目前，传统浮选工艺在回收上存在锡回收率低、带矸量大、药剂用量大等问题。本研究首次采用单十二烷基磷酸钠（SMP）作为疏水改性剂对细粒锡石进行预处理，实现矿物的选择性疏水团聚，从而提高其与传统捕收剂水杨基羟肟酸（SHA）的浮选回收率。浮选实验结果表明，在最佳条件下，SHA对−23 μm锡石的浮选效果较差，回收率仅为14.69%。在不改变浮选条件的情况下，采用SMP（搅拌转速700 rpm、pH = 9、SMP浓度130 mg/L、搅拌时间5 min）预处理细粒锡石，回收率可达80.39%（提高65.70%）。此外，人工混矿浮选实验证实，SMP对锡石具有良好的选择性疏水团聚作用，可在锡石-石英混合体系中选择性提高锡石的回收率。此外，通过一系列表面分析技术，阐明了smp诱导浮选增强的机理。SMP以其磷酸基作为锚定位点与锡石表面的Sn原子形成化学键，最终生成稳定的Sn- o - p - o -Sn五元环螯合物吸附在锡石表面。这加强了颗粒间疏水相互作用，促进锡石团聚，增加矿物的表观粒度，从而加强浮选回收率。本研究为细粒锡石的高效浮选提供了一种新的疏水改性剂和可行的策略。

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引用次数: 0

Effect of blade configuration and screw pitch on granular flow and heat transfer in industrial-scale screw conveyors: A DEM study 叶片构型和螺距对工业规模螺旋输送机颗粒流动和传热影响的数值模拟研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-25 DOI: 10.1016/j.powtec.2026.122165

Shuai Wang , Xushu Zeng , Yuxin Ge , Zhanheng Zhu , Kun Luo , Jianren Fan

Industrial-scale screw conveyors are widely employed for the efficient conveying and heating of particulate materials; however, the particle dynamics and heat transfer characteristics within such systems remain insufficiently understood. In this study, a high-fidelity discrete element method (DEM) model was employed to systematically investigate the influence mechanisms of two key design parameters (i.e., screw blade configurations and screw pitch) on particle flow behavior, residence time, temperature distribution, and mixing uniformity. The results reveal that increasing the pitch from 200 mm to 400 mm significantly and almost linearly enhances both conveying and heating rates; however, an excessively large pitch compromises heat retention at the outlet, while a 300 mm pitch achieves the optimal balance between conveying efficiency and heat transfer performance. The baffle configuration extends particle residence time by approximately 10%, improves longitudinal lifting and tumbling, and slightly enhances mixing uniformity. The chain configuration increases residence time by about 50% and promotes more thorough mixing, yet tends to generate stagnant zones in the mid-section of the conveyor. A particle size segregation effect is observed, with fine particles accumulating in the lower layers and coarse particles in the upper layers. While this stratification enlarges the effective heat transfer contact area, excessive segregation can conversely hinder overall heat transfer. These findings provide a systematic theoretical foundation and practical engineering guidance for the structural optimization and parameter selection of industrial-scale screw conveyors.

工业规模的螺旋输送机广泛用于颗粒物料的高效输送和加热；然而，粒子动力学和传热特性在这样的系统仍然不够充分的了解。本文采用高保真离散元法（DEM）模型，系统研究了两个关键设计参数（螺杆叶片构型和螺杆螺距）对颗粒流动行为、停留时间、温度分布和混合均匀性的影响机理。结果表明：当节距从200 mm增加到400 mm时，输送速率和加热速率均显著提高，且几乎呈线性增加；然而，过大的节距会损害出口的保热性，而300毫米的节距可以实现输送效率和传热性能之间的最佳平衡。挡板结构使颗粒停留时间延长了约10%，改善了纵向提升和翻滚，并略微提高了混合均匀性。链条的配置增加了大约50%的停留时间，促进更彻底的混合，但往往在输送机的中段产生停滞区。观察到粒度偏析效应，细颗粒在下层积聚，粗颗粒在上层积聚。虽然这种分层扩大了有效的传热接触面积，但过度的偏析反过来会阻碍整体传热。研究结果为工业规模螺旋输送机的结构优化和参数选择提供了系统的理论依据和工程实践指导。

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引用次数: 0

Preparation of modified magnesium hydroxide using CO2 and investigation of its properties CO2改性氢氧化镁的制备及其性能研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-23 DOI: 10.1016/j.powtec.2026.122169

Zheng-Hao Li , Li Zhang , Yu-Cui Yang , Xue-Yuan Guo , Ye Sheng , Bing Zhou

In this study, carbon dioxide (CO₂) and magnesium oxide (MgO) were employed as raw materials to develop a method for preparing multilayer plate-like magnesium hydroxide (MH) via CO₂ utilization, followed by surface modification with stearic acid (SA). The products were characterized by using Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR) to analyze their crystal plane distribution, morphology, and functional groups. In addition, thermogravimetric analysis (TGA) was conducted to investigate the decomposition temperatures. Furthermore, molecular dynamics simulations were performed to elucidate the structural arrangement of SA on the MH surface. This work proposes a novel strategy for synthesizing active MH by employing gaseous CO₂ instead of conventional industrial precursors, thereby reducing environmental pollution, lowering production costs, and enabling a milder reaction process. The findings provide theoretical guidance for the subsequent development of cost-effective and environmentally friendly industrial-scale production.

本研究以二氧化碳（CO2）和氧化镁（MgO）为原料，开发了利用CO2制备多层片状氢氧化镁（MH）的方法，并用硬脂酸（SA）进行表面改性。采用粉末x射线衍射（PXRD）、扫描电镜（SEM）和傅里叶变换红外光谱（FTIR）对产物进行了表征，分析了其晶体平面分布、形貌和官能团。此外，采用热重分析（TGA）对分解温度进行了研究。此外，通过分子动力学模拟来阐明SA在MH表面的结构排列。本研究提出了一种利用气态CO2代替传统工业前体合成活性MH的新策略，从而减少了环境污染，降低了生产成本，并使反应过程更加温和。研究结果为后续发展具有成本效益和环境友好的工业规模生产提供了理论指导。

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引用次数: 0

Development and analysis of micro-performance dynamics of rotary blade using discrete element method 基于离散元法的旋转叶片微性能动力学研究与分析

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-30 DOI: 10.1016/j.powtec.2026.122210

Rohit Dilip Nalawade , Krishna Pratap Singh , Ajay Kumar Roul , Shital Sonawane , Abhishek Patel , Aman Mahore , Mohit Kumar , Kanupriya Chaudhary , Pramod Shelake

Tillage operations in black cotton soils are associated with high energy consumption due to their pronounced moisture-dependent shrink-swell behavior. This study proposes a macro-geometric modification of the conventional L-shaped rotary blade to reduce penetration resistance by altering the soil failure mechanism from compression-dominated to tensile–shear-dominated modes. The micro-mechanical interactions of soil model and blades with sweepback angles of 0°, 6°, 12°, and 18° were investigated using Discrete Element Method (DEM) simulations. To represent the elastoplastic and cohesive behavior of the soil, a hysteretic spring contact model coupled with a linear cohesion model was used. The DEM parameters were calibrated using Cone Penetration Test (CPT). The numerical results were validated against soil-bin experiments (R² = 0.97). The results reveal a clear inverse relationship between sweepback angle and penetration torque. The 18° sweepback angle reduced peak torque by 21.98% and average penetration torque by 20.94% compared with the conventional 0° blade, primarily due to the reduced attack surface area and the associated wedging effect. In addition, the number of soil particles thrown decreased by 25.16%, indicating a reduction in kinetic energy transfer to the soil mass. These findings demonstrate the capability of calibrated DEM simulations to capture micro-mechanical interactions between tool geometry and cohesive granular media. It suggests that incorporating a sweepback angle in L-shaped rotary blades can improve energy efficiency in rotary tillage operations.

黑棉土壤的耕作作业由于其明显的水分依赖收缩膨胀行为而与高能耗相关。本研究提出对传统l型旋转叶片进行宏观几何修改，将土体破坏机制从压缩为主转变为拉剪为主，从而降低侵彻阻力。采用离散元法（DEM）模拟土壤模型与叶片在0°、6°、12°和18°后掠角下的微观力学相互作用。为了描述土的弹塑性和黏聚特性，采用了一个耦合线性黏聚模型的滞回弹簧接触模型。采用锥体穿透测试（CPT）对DEM参数进行校准。数值结果与土壤箱试验结果一致（R2 = 0.97）。结果表明，回扫角与侵彻扭矩之间存在明显的反比关系。与传统的0°叶片相比，18°后掠角使峰值扭矩降低了21.98%，平均侵彻扭矩降低了20.94%，这主要是由于攻击面面积减小以及相关的楔形效应。此外，抛掷的土粒数减少了25.16%，表明向土体传递的动能减少。这些发现表明，经过校准的DEM模拟能够捕捉工具几何形状和粘性颗粒介质之间的微观力学相互作用。结果表明，在l型旋转叶片中加入一个后掠角可以提高旋耕机的能效。

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引用次数: 0

Study on the relationship between coal fracture characteristics and particle migration and the evolution law of seepage characteristics 煤体裂隙特征与颗粒迁移关系及渗流特征演化规律研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-30 DOI: 10.1016/j.powtec.2026.122204

Shuyang Sun , He Yang , Zhen Liu , Jinrui Hu , Weiqun Wang , Shilong Zhang , Shuangyue Wang , Wenxin Li

The migration of coal particles during coal seam water injection strongly affects the permeability and clogging of coal fractures. In this study, water injection experiments were conducted on fractures filled with fine coal particles using a visual experimental system to observe particle migration and fracture evolution. The effects of flow rate (30–40 mL/min) and filling mass (2–3.5 g) on fracture structural evolution were analyzed. Fracture morphology was quantified via fractal dimension analysis, and a Kozeny-Carman permeability model was developed. Results show that with increasing flow rate and time, porosity rose from 6.0% to 36.5%, and fractal dimension D₂ from 1.67 to 1.95, exhibiting a strong positive correlation (R² = 0.9048). Correspondingly, the permeability coefficient increased by over two orders of magnitude (from 4.9 × 10⁻⁴ cm/s to 6.3 × 10⁻² cm/s), suggesting that water flushing and particle rearrangement restored seepage capacity. With a higher mass-to-size ratio (m/d), the permeability difference between filled and unfilled fractures decreased. These results quantitatively reveal the coupled mechanism of water flow, particle migration, and structural evolution, providing a theoretical basis for optimizing water injection in coal seams.

煤层注水过程中煤颗粒的运移对煤层裂隙的渗透性和堵塞性影响很大。本研究采用可视化实验系统对充填细粒煤的裂隙进行注水实验，观察颗粒运移和裂隙演化。分析了流量（30 ~ 40 mL/min）和充填质量（2 ~ 3.5 g）对裂缝结构演化的影响。通过分形维数分析对裂缝形态进行量化，建立了Kozeny-Carman渗透率模型。结果表明：随着流量和时间的增加，孔隙度从6.0%上升到36.5%，分形维数D₂从1.67上升到1.95，呈强正相关（R2 = 0.9048）；相应的，渗透系数增加了两个多数量级（从4.9 × 10−4 cm/s增加到6.3 × 10−2 cm/s），表明水冲刷和颗粒重排恢复了渗流能力。随着质量尺寸比（m/d）的增大，充填裂缝与未充填裂缝的渗透率差异减小。这些结果定量地揭示了水流、颗粒运移和构造演化的耦合机制，为煤层注水优化提供了理论依据。

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引用次数: 0

Mass flow rate prediction for gas-controlled hopper discharge of free-flowing granular materials 自由流动颗粒物料气控料斗卸料质量流量预测

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-28 DOI: 10.1016/j.powtec.2026.122190

Tingwen Li , Erik Delsman , Sreekanth Pannala

The reliable and predictable discharge of granular materials from hoppers is critical for numerous industrial processes. This paper presents an analytical model, extended from the early work by Ducker et al. 1985, to predict the mass flow rate of free-flowing granular materials from hoppers under gas-controlled conditions. The model's predictive capabilities were validated against several sets of experimental data from the literature, covering both gas-augmented and gas-impeded discharge scenarios. For further analysis and comparison, two-dimensional (2D) axi-symmetric computational fluid dynamics (CFD) simulations using a two-fluid model were also conducted for selected cases. Both the analytical model and CFD simulations yielded good agreement with the experimental data on solids mass flow rates. The models were then applied to the design and optimization of a commercial hopper operating under high-pressure conditions.

可靠和可预测的颗粒物料从料斗排出是许多工业过程的关键。本文提出了一个解析模型，该模型是Ducker等人1985年早期工作的扩展，用于预测气体控制条件下自由流动的颗粒物料从料斗中流出的质量流量。根据文献中的几组实验数据验证了该模型的预测能力，包括气体增加和气体阻碍排放两种情况。为了进一步分析和比较，还对选定的情况进行了采用双流体模型的二维轴对称计算流体力学（CFD）模拟。分析模型和CFD模拟结果与实验数据吻合较好。然后将该模型应用于高压条件下商用料斗的设计和优化。

引用次数: 0

Optimization on pressure pulsation and erosion for a solid-liquid two-phase multistage centrifugal pump 固液两相多级离心泵压力脉动与冲蚀优化

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-28 DOI: 10.1016/j.powtec.2026.122213

Baoling Cui , Yifan Lian , Zhifeng Lin , Zhongcun Su , Yuzhen Jin

Unsteady pressure pulsations and erosion caused by the high-speed rotation of the impeller are primary contributors to failure in solid-liquid two-phase multistage centrifugal pumps. In this study, impeller blades were optimized to reduce pressure pulsation intensity in the vaneless region between the impeller and guide vanes, and to minimize impeller erosion under design flow conditions with a particle concentration of 3% and a particle diameter of 0.3 mm. The optimization strategy encompassing the first, middle, and last stages was proposed based on a comparative analysis of performance and internal flow characteristics of each stage. The solid-liquid two-phase flow field was numerically simulated using CFD-DPM method. The Kriging surrogate model based on response-surface methodology was integrated with NSGA-II algorithm to achieve global optimization and produce an optimized blade profile. Near the blade leading edge, near-wall particle accumulation diminished as particles migrated toward the mid-passage region, coinciding with increased turbulent kinetic energy in this area. The elevated relative velocity at the blade trailing edge reduced the particle residence time within the impeller passages. Furthermore, the local backflow and rotor-stator interaction were alleviated by decreasing the guide vane inlet angle. As a result, the average pressure pulsation intensity in the vaneless region between the impeller and guide vanes decreased by 3.175%, and the average erosion rate of the impeller declined by 13.444%.

在固液两相多级离心泵中，叶轮高速旋转引起的非定常压力脉动和冲蚀是导致泵失效的主要原因。在颗粒浓度为3%、颗粒直径为0.3 mm的设计流动条件下，对叶轮叶片进行优化，以减小叶轮与导叶之间无叶区域的压力脉动强度，最大限度地减少叶轮冲蚀。在对各级性能和内部流动特性进行对比分析的基础上，提出了包括前、中、末级的优化策略。采用CFD-DPM方法对固液两相流场进行了数值模拟。将基于响应面法的Kriging代理模型与NSGA-II算法相结合，实现全局优化，得到最优叶片型线。在叶片前缘附近，随着颗粒向通道中部区域迁移，近壁面颗粒积累减少，与此区域湍流动能增加相一致。叶片尾缘相对速度的提高减少了颗粒在叶轮通道内的停留时间。此外，减小导叶进口角可以缓解局部回流和动静相互作用。叶轮与导叶之间无叶区域的平均压力脉动强度降低了3.175%，叶轮的平均冲蚀率降低了13.444%。

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引用次数: 0

Laser powder bed fusion of nano-SiO₂/AlSi10Mg composites for lightweight optical applications 用于轻型光学应用的纳米sio₂/AlSi10Mg复合材料的激光粉末床融合

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-27 DOI: 10.1016/j.powtec.2026.122180

Zhijian Feng , Wei Han , Thorsten H. Becker , Lingbao Kong

Laser powder bed fusion (LPBF) technology holds significant application potential in the manufacturing of lightweight, high-precision aluminum alloy components, yet challenges remain in controlling melt pool behavior and suppressing defects. This study introduced 0.5 wt% nano-SiO₂ into the AlSi10Mg powder system to enhance powder flowability and systematically evaluated its effects on the density, microstructure, and mechanical properties of LPBF-formed parts. Results indicate that nano-SiO₂ addition significantly improved powder flowability, achieving powder flow rate of 122 s/50 g, with a slight increase in bulk density, thereby promoting uniform powder spreading. Microstructural analysis revealed that nano-SiO₂ promoted heterogeneous nucleation and a minor influence on grain size. However, increased melt viscosity led to higher porosity in the parts, accompanied by localized oxide enrichment and microcrack formation. Compared to unmodified AlSi10Mg, the composite samples exhibited ∼16% and ∼ 48% reductions in tensile strength and elongation, respectively, while showing a slight increase in microhardness. Compression testing of the lattice structure revealed reduced peak load while retaining progressive densification characteristics. These results demonstrate the coupled influence of nano-SiO₂ on powder characteristics, melt pool dynamics, and macroscopic properties in LPBF-fabricated nano-SiO₂/AlSi10Mg composites, providing insights for the optimization of ceramic-modified aluminum alloy powders.

激光粉末床熔融（LPBF）技术在制造轻量化、高精度铝合金部件方面具有巨大的应用潜力，但在控制熔池行为和抑制缺陷方面仍存在挑战。本研究在AlSi10Mg粉末体系中引入0.5 wt%的纳米sio₂，以增强粉末的流动性，并系统评估其对lpbf成形零件的密度、微观结构和力学性能的影响。结果表明，纳米sio₂的加入显著改善了粉末的流动性，粉末流动速率达到122 s/50 g，同时粉末的容重略有增加，从而促进了粉末的均匀分布。微观结构分析表明，纳米sio2促进了非均相成核，对晶粒尺寸影响较小。然而，熔体粘度的增加导致零件孔隙率增加，并伴随着局部氧化物的富集和微裂纹的形成。与未经改性的AlSi10Mg相比，复合材料样品的抗拉强度和伸长率分别降低了~ 16%和~ 48%，而显微硬度略有增加。晶格结构的压缩测试表明，在保持渐进致密化特性的同时，峰值载荷有所降低。这些结果证明了纳米sio₂对lpbf制备的纳米sio₂/AlSi10Mg复合材料的粉末特性、熔池动力学和宏观性能的耦合影响，为陶瓷改性铝合金粉末的优化提供了见解。

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引用次数: 0

Investigation of ferronickel concentrate oxidation behavior and prevention strategies during drying 镍铁精矿干燥过程氧化行为及预防策略研究

IF 4.6 2区工程技术 Q2 ENGINEERING, CHEMICAL

Powder Technology

Pub Date : 2026-04-15 Epub Date: 2026-01-28 DOI: 10.1016/j.powtec.2026.122207

Wei Lv , Fanmao Wang , Siegfried Gautama , Mikaella Brillantes , Frederick D. Ford , Samuel Marcuson , Manqiu Xu , Mansoor Barati

Ferronickel serves as an essential feedstock to produce stainless steel. A ferronickel concentrate assaying 28% Ni was obtained via two-stage thermal treatment of ultramafic Ni sulfide concentrate followed by direct grinding and sieving without magnetic separation. However, microstructural and compositional analysis revealed that post-upgrading oxidation led to the formation of a Ni-wustite phase, comprising up to 13% of the ferronickel concentrate and accounting for 7.3% of the total Ni. The oxidation behavior of ferronickel under different grinding and drying conditions revealed that the formation of Ni-wustite predominantly occurs during the drying stage rather than during early wet grinding. Excessive grinding accelerates oxidation even drying is conducted in a non-oxidizing atmosphere. Drying under a non-oxidizing atmosphere or after solvent immersion significantly suppresses Ni-wustite formation. Furthermore, rinsing ferronickel concentrate with Na₂CO₃ solution prior to drying is recommended, as it forms a passivation layer on the ferronickel surface, creating a physical and chemical barrier that prevents oxygen contact and thereby inhibits oxidation. The key findings of this study provide guidance for selecting appropriate ferronickel grinding and drying conditions, enabling the maximal recovery of ferronickel alloys liberated by direct grinding without magnetic separation.

镍铁是生产不锈钢必不可少的原料。对超镁铁硫化镍精矿进行两段热处理，再进行直接磨矿和筛分，无需磁选，获得了含镍量为28%的镍铁精矿。然而，显微组织和成分分析表明，升级后氧化导致镍-浮氏体相的形成，该相占镍铁精矿的13%，占总Ni的7.3%。不同研磨和干燥条件下镍铁的氧化行为表明，ni -浮斯体的形成主要发生在干燥阶段，而不是湿磨初期。过度研磨加速氧化，甚至在非氧化气氛中进行干燥。在非氧化气氛下干燥或溶剂浸泡后，可显著抑制镍浮氏体的形成。此外，建议在干燥前用Na2CO3溶液冲洗镍铁精矿，因为它会在镍铁表面形成钝化层，形成物理和化学屏障，防止氧气接触，从而抑制氧化。研究结果为选择合适的镍铁研磨和干燥条件提供了指导，使直接研磨释放的镍铁合金得到最大限度的回收。

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引用次数: 0