Blade Segment with a 3D Lattice of Diamond Grits Fabricated via an Additive Manufacturing Process

Diamond tools with orderly arrangements of diamond grits have drawn considerable attention in the machining field owing to their outstanding advantages of high sharpness and long service life.This diamond super tool,as well as the manufacturing equipment,has been unavailable to Chinese enterprises for a long time due to patents.In this paper,a diamond blade segment with a 3D lattice of diamond grits was additively manufactured using a new type of cold pressing equipment(AME100).The equipment,designed with a rotary working platform and 16 molding stations,can be used to additively manufacture segments with diamond grits arranged in an orderly fashion,layer by layer;under this additive manufacturing process,at least 216000 pcs of diamond green segments with five orderly arranged grit layers can be produced per month.The microstructure of the segment was observed via SEM and the diamond blade fabricated using these segments was compared to other commercial cutting tools.The experimental results showed that the 3D lattice of diamond grits was formed in the green segment.The filling rate of diamond grits in the lattice could be guaranteed to be above 95%;this is much higher than the 90%filling rate of the automatic array system(ARIX).When used to cut stone,the cutting amount of the blade with segments made by AME100 is two times that of ordinary tools,with the same diamond concentration.When used to dry cut reinforced concrete,its cutting speed is 10%faster than that of ARIX.Under wet cutting conditions,its service life is twice that of ARIX.By applying the machine vision online inspection system and a special needle jig with a negative pressure system,this study developed a piece of additive manufacturing equipment for efficiently fabricating blade segments with a 3D lattice of diamond grits.

A Fast Charging–Cooling Coupled Scheduling Method for a Liquid Cooling-Based Thermal Management System for Lithium-Ion Batteries

Efficient fast-charging technology is necessary for the extension of the driving range of electric vehicles.However,lithium-ion cells generate immense heat at high-current charging rates.In order to address this problem,an efficient fast charging–cooling scheduling method is urgently needed.In this study,a liquid cooling-based thermal management system equipped with mini-channels was designed for the fastcharging process of a lithium-ion battery module.A neural network-based regression model was proposed based on 81 sets of experimental data,which consisted of three sub-models and considered three outputs:maximum temperature,temperature standard deviation,and energy consumption.Each sub-model had a desirable testing accuracy(99.353%,97.332%,and 98.381%)after training.The regression model was employed to predict all three outputs among a full dataset,which combined different charging current rates(0.5C,1C,1.5C,2C,and 2.5C(1C=5 A))at three different charging stages,and a range of coolant rates(0.0006,0.0012,and 0.0018 kg·s^(-1)).An optimal charging–cooling schedule was selected from the predicted dataset and was validated by the experiments.The results indicated that the battery module’s state of charge value increased by 0.5 after 15 min,with an energy consumption lower than 0.02 J.The maximum temperature and temperature standard deviation could be controlled within 33.35 and 0.8C,respectively.The approach described herein can be used by the electric vehicles industry in real fast-charging conditions.Moreover,optimal fast charging-cooling schedule can be predicted based on the experimental data obtained,that in turn,can significantly improve the efficiency of the charging process design as well as control energy consumption during cooling.

Model of Production Planning and Scheduling in Shop Floor Based on Collaboration and Competition

The planning and scheduling in real shop floor is actually achieved by coordination between different persons. In this process, cooperation is mainstream, but competition also exists, for example, the competition between different groups, operators with the same skill, etc. In multi-agent based shop floor management and control system, this competition and cooperation relation must be embodied. The general process of shop floor production planning and scheduling is studied, and a colored Petri-net model for the competition and cooperation process of three main agents in such system to achieve shop floor production planning and scheduling is presented. The evaluating method of bids in bidding process that especially embodies the competition relationship is also presented. This colored Petri-net model gives a clear illustration of this complex coordination process to system designers, effectively promotes the cooperative development.

Review of materials used in laser-aided additive manufacturing processes to produce metallic products

Rapid prototyping (RP) or layered manufacturing (LM) technologies have been extensively used to manufacture prototypes composed mainly of plastics, polymers, paper, and wax due to the short product development time and low costs of these technologies. However, such technologies, with the exception of selective laser melting and sintering, are not used to fabricate metallic products because of the resulting poor life, short cycle, poor surface finish, and low structural integrity of the fabricated parts. The properties endowed by these parts do not match those of functional parts. Therefore, extensive research has been conducted to develop new additive manufacturing (AM) technologies by extending existing RP technologies. Several AM technologies have been developed for the fabrication of metallic objects. These technologies utilize materials, such as Ni-, A1-, and Ti-based alloys and stainless steel powders, to fabricate high-quality functional components. The present work reviews the type of materials used in laserbased AM processes for the manufacture of metallic products. The advantages and disadvantages of processes and different materials are summarized, and future research directions are discussed in the final section. This review can help experts select the ideal type of process or technology for the manufacturing of elements composed of a given alloy or material (Ni, Ti, Al, Pb, and stainless steel).

Flexible,Light-Interacting,B-Shaped Structures for Computations

Integrating mechanical computing functions into robotic materials,microelectromechanical systems,or soft robotics can improve their intelligence in stimulation-response processes.Current mechanical computing systems exhibit limitations,including incomplete functions,unchangeable computing rules,difficulties in realizing random logic,and lack of reusability.To overcome these limitations,we propose a straightforward method of designing mechanical computing systems—based on the logic expressions—for complex computations.We designed soft,B-shaped mechanical metamaterial units,and compressed them to render stress inputs;the outputs are represented by the light-shielding effects caused by the unit deformations.We realized logic gates and corresponding combinations(including half/full binary adder/subtractor and addition/subtraction of 2 numbers with multiple bits)and provided a versatile solution for making a mechanical analog-to-digital converter to generate both ordered and disordered numbers.We performed all of the computations within the elastic regions of the B-shaped units;thus,after one computation,the systems can return to the initial states for reuse.The proposed mechanical computers will potentially enable robotic materials,microelectromechanical systems,or soft robotics to perform complex tasks.Furthermore,one can extend this concept to systems that are based on other mechanisms or materials.

Effect of stagger angle on capillary performance of microgroove structures with reentrant cavities

Aluminum-based microgroove surfaces with reentrant cavities (MSRCs) were fabricated by two staggered ploughing/extrusion processes to meet the requirements of lightweight phase change heat transfer devices.Five MSRCs with different stagger angles between cavities and microgrooves (MGs) were fabricated to study the effect of stagger angle on capillary performance.Capillary rise and permeability tests were performed on all MSRCs and the results were compared with MGs having the same processing parameters.It was found that MSRCs with smaller stagger angles have higher capillary height,and the maximum enhancement maintained by MSRC45 was about 54.84%.However,MSRCs with larger stagger angles were found to have higher permeability.Therefore,the capillary parameter K·ΔP_(cap)was used as a comprehensive index to evaluate these wicks.MSRC90 and MSRC75 obtained the largest K·ΔP_(cap)values without and with the effect of gravity considered,respectively.Although all MSRCs had a higher capillary rise height than MGs,smaller stagger angles (≤60°) seriously reduced the permeability of MSRCs and even resulted in smaller K·ΔP_(cap)value than that of MGs when calculated considering the effect of gravity.Therefore,MSRCs with larger stagger angles (≥75°) may be the optimum wicks due to the good balance between capillary pressure and permeability.

CONCURRENT PRODUCTION ENGINEERING SYSTEM FOR BUFFER SIZE AND FLEXIBLE TRANSFER LINE LAYOUT DESIGN

在这篇论文，我们建议一个并发的生产工程系统(处理) 为灵活转移线(FTL ) 在一个限制区域的布局设计。处理第一在 FTL 在每台机床的海湾前面决定缓冲区尺寸然后初始化一台计算机在一个限制区域拉 FTL 的帮助设计(CAD ) 系统。我们开发集成于一个单个框架的一套模块系统，根据并发的工程的实践。并发的工程包含这些活动的合作。它期望了发展处理能改进在生产工程师的家之间的合作和植物设计者。这能被启用做生产工程师将更好使决定考虑成为 FTL 缓冲区尺寸。

Robust design approach to the minimization of functional performance variations of products and systems

Functional performance variations of products and systems are often used to measure the qualities of products and systems considering the changes in the design parameter values caused by uncertainties.A robust design approach has been developed in this research to minimize the functional performance variations considering the design parameter uncertainties by identifying the boundaries of the functional performance variations through optimization.In this work,a mathematical model is developed to describe the relationships among functional performance,design configurations and parameters,and design parameter uncertainties.A multi-level optimization model is established to identify:(1)The optimal design configuration,(2)the optimal values of design parameters,and(3)the boundaries of functional performance variations.Sensitivity analysis considering the impact of parameter uncertainties on functional performance variation boundaries has also been conducted.A case study on the design of a truss system has been conducted.Case study results show that the sensitivities of functional performance variation boundaries to the design parameter uncertainties can be reduced significantly using the new robust design approach.