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Commodity Value Theory-Invisible Hands Seen
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作者 SHEN Youlian 《Management Studies》 2024年第2期124-127,共4页
Through the revelation of“commodity value”,the“invisible hand”described by Adam Smith is now clearly visible.It is precisely“commodity value”that guides people to seek benefits for themselves and for others,addi... Through the revelation of“commodity value”,the“invisible hand”described by Adam Smith is now clearly visible.It is precisely“commodity value”that guides people to seek benefits for themselves and for others,adding enormous wealth to society. 展开更多
关键词 the invisible hand has been seen
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Design of two-dimensional elliptically cylindrical invisible cloaks with multiple regions
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作者 罗孝阳 刘道亚 +1 位作者 刘锦景 董建峰 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期257-262,共6页
Two-dimensional (2D) elliptically cylindrical invisible cloaks with multiple regions are designed based on the trans-formation optics and the complementary media theory. Multiple invisible cloak regions can be obtai... Two-dimensional (2D) elliptically cylindrical invisible cloaks with multiple regions are designed based on the trans-formation optics and the complementary media theory. Multiple invisible cloak regions can be obtained by properly using the compressed or folded transformation in each space layer. The constitutive parameter tensor expressions for each re- gion have been obtained. The results of full wave simulations by using finite element software confirm the validity of the constitutive parameter tensor expressions. In addition, the parameters are relatively easier to realize. 展开更多
关键词 transformation optics complementary media theory elliptically cylindrical invisible cloaks
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Invisible Web研究综述 被引量:19
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作者 黄晓冬 《情报科学》 CSSCI 北大核心 2004年第9期1144-1148,共5页
本文对有关 Invisible Web的内容进行了全面、详细地介绍。首先论述了什么是 Invisible Web以及为什么要研究 Invisible Web,同时介绍了两个相关概念 ;其次对 Invisible Web不可见的原因加以分析 ;对 Invisible Web的类型进行了划分 ;... 本文对有关 Invisible Web的内容进行了全面、详细地介绍。首先论述了什么是 Invisible Web以及为什么要研究 Invisible Web,同时介绍了两个相关概念 ;其次对 Invisible Web不可见的原因加以分析 ;对 Invisible Web的类型进行了划分 ;介绍了 Invisible Web的检索工具 ;最后总结了 Invisible Web研究的方向。 展开更多
关键词 invisible WEB DEEP WEB 信息检索 搜索引擎
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小说Invisible Man的几种译法 被引量:1
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作者 刘彬 《衡阳师范学院学报》 2008年第5期148-151,共4页
美国黑人作家拉尔夫.艾里森的长篇小说Invisible Man在国内出现了三种译法:"无形人"、"隐形人"和"看不见的人"。这三种译法都一语道破美国黑人被忽视的生存状态。"失明"和"追求自我"... 美国黑人作家拉尔夫.艾里森的长篇小说Invisible Man在国内出现了三种译法:"无形人"、"隐形人"和"看不见的人"。这三种译法都一语道破美国黑人被忽视的生存状态。"失明"和"追求自我"是这部小说的两个重要的主题成分。结合这两个主题来探讨,在三种译法中,"看不见的人"既反映了黑人的生存境遇,又凸显了"自我追寻"和"失明"的主题。 展开更多
关键词 无形人 隐形人 看不见的人 自我追寻 失明
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Individual Identity and Collective Identity in Ralph Ellison's Invisible Man
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作者 韩秀 《海外英语》 2015年第8期153-155,共3页
Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,t... Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,the paper focuses on the conflict between his need to build a distinctive individual identity with the prerequisite to surrender to collective identity in order to blend in the group. 展开更多
关键词 invisible MAN INDIVIDUAL IDENTITY COLLECTIVE IDENTITY
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水田动力底盘逆向建模与质心验证——基于Geomagic Design X
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作者 何剑飞 曾志浩 +5 位作者 郭梓游 李贵蓉 钟文能 钟顺 王在满 李庆 《农机化研究》 北大核心 2024年第10期248-253,共6页
针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动... 针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动力底盘为例,将测得的实际质心位置与所建的模型质心位置进行比较,并对提出的逆向建模方法进行了试验验证以及误差分析。结果表明:总质量、x坐标、y坐标、z坐标的误差值分别为4.55%、3.62%、2.23%、4.81%,误差值均在5%内。此方法可构建准确的三维模型,为后续仿真优化数据精确性奠定了基础,与传统的研发相比较,可缩短农业机械研发周期、降低设计成本。 展开更多
关键词 水田 动力底盘 逆向建模 质心验证 Geomagic design X 数字样机
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invisible hand 小议
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作者 符延军 《语言教育》 2001年第3期21-21,共1页
invisible hand 是由英国人亚当·斯密(Adam Smith)首先提出来的。Adam Smith(1723—1790)是英国苏格兰人,经济学家与哲学家。他于1776年完成了经济学史上的经典著作《国富论》(The Wealth of Na-
关键词 经济学史 苏格兰人 国富论 WEALTH invisible hand 英语表达 看不见的手 经济学体系 西方政治 allowed
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App Designer辅助教学方法探索与实践——以软件无线电课程为例
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作者 向新 刘宇峰 +2 位作者 梁源 王瑞 何林远 《中国现代教育装备》 2024年第19期148-151,共4页
软件无线电作为通信学科的必修课程,具有承上启下的重要作用。因课程原理抽象、理论公式复杂,学员在学习过程存在理解掌握难、实践应用难等问题。通过对当前软件无线电教学过程中存在的不足与困难进行分析,提出利用MATLAB App Designer... 软件无线电作为通信学科的必修课程,具有承上启下的重要作用。因课程原理抽象、理论公式复杂,学员在学习过程存在理解掌握难、实践应用难等问题。通过对当前软件无线电教学过程中存在的不足与困难进行分析,提出利用MATLAB App Designer辅助课程教学,从教学准备、课堂互动、自主实验、反馈提升四个方面开展课程教学改革。实践表明,该方法对于提升学员的工程思维、系统思维具有显著效果,同时可以增强学员理论联系实际的能力。 展开更多
关键词 软件无线电 MATLAB App designer 教学方法改革 理实结合
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如何利用Invisible-web获取更多的网络信息资源
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作者 生修雯 《科技广场》 2008年第7期155-157,共3页
在浩瀚如海的网络世界里,信息资源犹如海洋生物,大大小小,无孔不入,如何能够快速而准确地找到并获取自己所需的信息,成为我们这个时代最需解决的根本问题之一。当然,利用各种搜索引擎可以查找到很多信息资源,但是也有一些信息通过搜索... 在浩瀚如海的网络世界里,信息资源犹如海洋生物,大大小小,无孔不入,如何能够快速而准确地找到并获取自己所需的信息,成为我们这个时代最需解决的根本问题之一。当然,利用各种搜索引擎可以查找到很多信息资源,但是也有一些信息通过搜索引擎是无法找到的,它们隐藏在这个网络世界的某个角落,因为某种原因而不为大多人所熟知,但是这些信息本身却有着很高的使用价值。美国的Sherman·C等人把这些资源命名为"看不见的网站(Invisible—web)"。"看不见的网站"里拥有信息检索人员难以置信的有价值的资源。本文阐述了"看不见的网站"的含义及价值,指出信息检索人员应该如何有效利用"看不见的网站"资源,最后提供一些查找"看不见网站"的途径与工具。 展开更多
关键词 网络信息资源 搜索引擎 看不见的网站
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New insights into the extraction of invisible gold in a low-grade high-sulfur Carlin-type gold concentrate by bio-pretreatment 被引量:4
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作者 Xiao-bin Qiu Jian-kang Wen +3 位作者 Song-tao Huang Hong-ying Yang Mei-lin Liu Biao Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第10期1104-1111,共8页
To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching pr... To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content. 展开更多
关键词 GOLD ore invisible GOLD bio-pretreatment mineralogy LIBERATION analysis secondary product CARBONACEOUS matter
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From Savior to Restrictive Mother——Transformation of Mary Rambo in Invisible Man
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作者 王丽君 《英语广场(学术研究)》 2012年第5期19-21,共3页
Invisible Man is Ralph Ellison's most important work,the hero of which is confused by the problem of his identity.This thesis will discuss the transformation of Mary Rambo in the novel.At the beginning,Mary Rambo ... Invisible Man is Ralph Ellison's most important work,the hero of which is confused by the problem of his identity.This thesis will discuss the transformation of Mary Rambo in the novel.At the beginning,Mary Rambo was a symbol of hope and encouragement for the hero and a kind of salvation and redemption to him both materially and spiritually.But later,she changed from a savior to a restrictive mother.The hero became restive and guilty under her watchful and anxious care.Thus,the hero must escape her in order to continue his search for identity. 展开更多
关键词 invisible Man TRANSFORMATION Mary Rambo
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Efficacy of invisible advancement correction for mandibular retraction in adolescents based on Pancherz analysis 被引量:1
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作者 Lei Kong Xin-Qiang Liu 《World Journal of Clinical Cases》 SCIE 2023年第6期1299-1309,共11页
BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the tempor... BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the temporomandibular joint.The use of mandibular advancement(MA)devices has recently emerged as an adolescent mandibular retraction treatment;however,current studies regarding the effect thereof are relatively few,and there is lack of sufficient clinical support.AIM To investigate the clinical effect of invisalign MA on the treatment of mandibular retraction in adolescents.METHODS This study included 30 adolescent patients who underwent treatment with the MA appliances from December 2017 to June 2021.The lateral cephalometric data before and after treatment were collected and imported into Dolphin Imaging software.The changes were measured by linear measurement superimposed with lateral cephalometric trajectory based on the Pancherz technology.RESULTS There was no significant difference in the length and position of maxilla before and after the treatment.The position of the mandible moved 3.13 mm,the length increased 4.14 mm,the mandibular ramus length increased 4.09 mm,the body length increased 4.25 mm,and the position of the condyle moved 1.03 mm forward after treatment.Additionally,changes in the incisor sagittal position and labial inclination were observed.The position of the upper incisor point moved back 1.33 mm,without statistical difference,the inclination and tooth angle decreased by 3.44°and 4.06°,respectively;the position of the lower incisor point was moved 2.98 mm,and the inclination and tooth angle increased by 2.62°and 1.23°,respectively.Furthermore,changes in the incisor overjet and molar relationship were seen.Overjet decreased by 4.31 mm,of which 1.78 mm was due to dental factors,accounting for 41.3%of the effect as opposed to 58.7%due to skeletal factors.Molar relationship improved 3.87 mm,with 1.34 mm due to dental factors,and dental and skeletal factors were accounted for 34.6%and 65.4%of the effect,respectively.CONCLUSION For adolescent patients with mandible retraction,invisalign MA can effectively promote the mandible growth,and it was proven to be mainly due to skeletal effects. 展开更多
关键词 Mandibular retraction ADOLESCENT Pancherz technology Functional correction invisible appliance Mandibular advancement
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The Discussion of Racial Identity of the Protagonist in the Invisible Man from Post-Colonial Perspective
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作者 张倩 《疯狂英语(理论版)》 2016年第4期175-177,共3页
The African-American novel Invisible Man written by Ralph Ellison is about the miserable suffering of black people in the white society.The black people were invisible in the white world.This thesis analyzes this nove... The African-American novel Invisible Man written by Ralph Ellison is about the miserable suffering of black people in the white society.The black people were invisible in the white world.This thesis analyzes this novel from post-colonialism perspective to discuss the process of looking for the racial identity of the protagonist. 展开更多
关键词 IDENTITY POST-COLONIALISM invisible Man
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Nonsingularity in two-dimensional cylindrical invisible cloaks
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作者 王新华 屈绍波 +8 位作者 夏颂 王斌科 徐卓 马华 王甲富 顾超 吴翔 鲁磊 周航 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期293-296,共4页
The method of designing electromagnetic invisible cloaks is usually based on the form-invariance of Maxwell's equations in coordinate transformation. The exterior boundary of a cylindrical invisible cloak is unchange... The method of designing electromagnetic invisible cloaks is usually based on the form-invariance of Maxwell's equations in coordinate transformation. The exterior boundary of a cylindrical invisible cloak is unchanged and the interior boundary is extended from that of a point to that of a cylindrical region in coordination transformation. This transformation process makes perfect cloaks, but it causes singularity in the constitutive material parameters of cloaks. This singularity makes the cloaks impossible to realize in practice. In order to remove this singularity, this paper sets a small cylindrical region replacing a point in the space transformation. The cylindrical region is so small that it does not affect the invisibility effects, but it can remove the singularity for material parameters. Full wave simulations based on the finite element method were used to verify the designed cloaks. 展开更多
关键词 invisible cloak arbitrary shapes SINGULARITY constitutive material parameters
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Invisible anti-cloak with elliptic cross section using phase complement
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作者 杨钰琦 张民 岳建祥 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期224-228,共5页
Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invi... Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invisible than that with circular cross section, a scaled coordinate system is proposed to design equivalent materials of invisible anti- cloak with elliptic cross section using phase complement. The cloaks with conventional dielectric and double negative parameters are both simulated with the geometrical transformations. The results show that the cloak with elliptic cross section through phase complement can effectively hide the outside objects. 展开更多
关键词 invisible anti-cloak phase complement electromagnetic radiation
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Multi-window invisible cloaks
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作者 王新华 屈绍波 +8 位作者 夏颂 王斌科 徐卓 马华 王甲富 顾超 吴翔 鲁磊 周航 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期289-292,共4页
This paper reports that a general method of designing invisible cloaks is using variant constitutive material parameters to realize the space transformation. A hollow region can be hidden after this transformation. It... This paper reports that a general method of designing invisible cloaks is using variant constitutive material parameters to realize the space transformation. A hollow region can be hidden after this transformation. It was recently shown (Ma H, Qu S B, Xu Z and Wang J F 2009 Appl. Phys. Lett. 94 103501) that when the original point moves to the boundary of a cloak, the cloak can be designed to be open. Based on this theory, we propose multi-window invisible cloaks which can conceal a group of objects. Full wave simulations for invisible cloaks with regular and irregular shapes verified this method. 展开更多
关键词 invisible cloaks transformation optics constitutive material parameters
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Experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line metamaterials
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作者 刘国昌 李超 方广有 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期247-252,共6页
We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line(TL) metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiti... We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line(TL) metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiting anisotropic effective material parameters, while the background medium consists of isotropic TL unit cells. The simulated and the measured field patterns around the cloak show a fairly good agreement, both demonstrate that the fabricated cloak can shield the cloaked interior area from electromagnetic fields without perturbing the external fields. The scattering of the cloaked perfect electric conductor(PEC) is minimized. Furthermore, the nonresonant property of the TL structure results in a relatively broad bandwidth of the realized cloak, which is clearly observed in our experiment. 展开更多
关键词 invisible cloak irregular shape tensor transmission line metamaterials
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Design method of reusable reciprocal invisibility and phantom device
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作者 Cheng-Fu Yang Li-Jun Yun Jun-Wei Li 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期382-390,共9页
Reusable reciprocal invisibility and phantom device is proposed and designed based on multi-folded transformation optics and equivalent components. In comparison with the reported reciprocal invisibility cloaks, the m... Reusable reciprocal invisibility and phantom device is proposed and designed based on multi-folded transformation optics and equivalent components. In comparison with the reported reciprocal invisibility cloaks, the material parameters of the device presented here are homogeneous, and the hiding of the target object does not require any “anti-object” at all,which dramatically breaks through the limitations of the “anti-object” design in previous reciprocal cloak design. Perfectly illusion effect is also found by reasonably setting the material parameters of the restored medium of the device, which can be used to confuse detection radars while hiding target objects. Last but not least, the proposed device has an open structure,which enables the target object enclosed by the device to perform material exchange and simplex transfer of information with the outside world through open channels. In other words, the proposed device has a reusable function, enabling stealth or phantom of new target objects without changing any parameters of the device. 展开更多
关键词 transformation optics reciprocal cloak ILLUSION invisIBILITY
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Research on the Property of New Tricot Invisible Curtain Fabric
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作者 陈慰来 郑倩 +2 位作者 于斌 高营 朱建效 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期863-868,共6页
The new designed curtain fabric,whose two faces were covered by trilobal cross-sectional filament and dull polyester filament,was designed with three-bar tricot stitch,which possessed unique style with implicit grid e... The new designed curtain fabric,whose two faces were covered by trilobal cross-sectional filament and dull polyester filament,was designed with three-bar tricot stitch,which possessed unique style with implicit grid effects.Tricot two-sided technology was adopted in this paper and the method of spectrophotometer was used to test the optical properties,including the light transmittance and reflectance of the technical face and back side of the samples in the ultraviolet,visible,and near-infrared band.The results show that the transmittance and invisible,anti-ultraviolet properties in the thin and single-layer fabric are improved.The fabric meets the qualifications in use of curtain material. 展开更多
关键词 tricot invisible double-sided morphology optical property
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Alloy design for laser powder bed fusion additive manufacturing:a critical review 被引量:3
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作者 Zhuangzhuang Liu Qihang Zhou +4 位作者 Xiaokang Liang Xiebin Wang Guichuan Li Kim Vanmeensel Jianxin Xie 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期29-63,共35页
Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using exi... Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using existing alloys for laser powder bed fusion(L-PBF)AM have persisted.These challenges arise because commercial alloys are primarily designed for conventional casting or forging processes,overlooking the fast cooling rates,steep temperature gradients and multiple thermal cycles of L-PBF.To address this,there is an urgent need to develop novel alloys specifically tailored for L-PBF technologies.This review provides a comprehensive summary of the strategies employed in alloy design for L-PBF.It aims to guide future research on designing novel alloys dedicated to L-PBF instead of adapting existing alloys.The review begins by discussing the features of the L-PBF processes,focusing on rapid solidification and intrinsic heat treatment.Next,the printability of the four main existing alloys(Fe-,Ni-,Al-and Ti-based alloys)is critically assessed,with a comparison of their conventional weldability.It was found that the weldability criteria are not always applicable in estimating printability.Furthermore,the review presents recent advances in alloy development and associated strategies,categorizing them into crack mitigation-oriented,microstructure manipulation-oriented and machine learning-assisted approaches.Lastly,an outlook and suggestions are given to highlight the issues that need to be addressed in future work. 展开更多
关键词 laser powder bed fusion alloy design PRINTABILITY crack mitigation
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