Scan Strategy in Electron Beam Selective Melting

来源 :Tsinghua Science and Technology | 被引量 : 0次 | 上传用户:lijingbo1985
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
In electron beam selective melting process, powder pushed-away phenomena and uneven temperature field are two main obstacles, which are greatly associated with the electron beam scan mode. In this paper, various scan strategies, including iterative scan mode, reverse scan mode, interlaced reverse scan mode, randomized block scan mode, and constant length scan mode, are investigated. The analyses for each scan strategy are presented based on the influence to the temperature field over the formation zone and the powder pushed-away phenomena. The most promising strategy, interlaced reverse scan mode, is approved by the ANSYS simulation and a two-dimensional scan experiment. The result shows interlaced reverse scan mode can improve the uniformity of the temperature field and reduce the powder pushed-away phenomena. In electron beam selective melting process, powder pushed-away phenomena and uneven temperature field are two main obstacles, which are greatly associated with the electron beam scan mode. In this paper, various scan strategies, including iterative scan mode, reverse scan mode, interlaced reverse scan mode, randomized block scan mode, and constant length scan mode, are investigated. The analyzes for each scan strategy are presented based on the influence to the temperature field over the formation zone and the powder pushed-away phenomena. The most promising strategy , interlaced reverse scan mode, is approved by the ANSYS simulation and a two-dimensional scan experiment. The result shows interlaced reverse scan mode can improve the uniformity of the temperature field and reduce the powder pushed-away phenomena.
其他文献
华阴方言属北方方言中原官话关中片的一个地点方言。本文对华阴方言有关缝纫动作的四个动词“缘”、“■”、“敹”、“纳”逐一进行考证,并对它们在华阴方言中的不同意义进
利用JB19等程序分别对基频和倍频激光驱动条件下类氖锗X射线激光进行了模拟计算,结果表明利用倍频激光驱动同样也能够获得高强度的类氖锗X射线激光输出,只是对驱动激光的输出
近年,对热轧带钢厚度的要求越来越严格。同时,以炼钢与热轧带钢生产的同步化为目的,要求放宽对轧制计划的制约,使热带精轧机的轧制条件大幅度变化,因此确立与之相适应的高精
在超高速切削加工中,提高主运动切削速度有极其深远的意义,目前,超高速切削机床的主运动切削速度一般为传统金属切削机床的5~10倍。但是,超高速切削加工中,主运动速度的提高,
Fe-Ni合金系中,如果Ni含量为29~33wt%时,可产生针状或块状的马氏体,产生孪晶组织的马氏体相变,对合金的因瓦特性,往往导致不良后果,本实验在M_3点以下的-10~-60℃正电子展宽谱中
我厂水压机车间煤气管道上的一个 DG600的阀门,在阀体上有三道裂纹产生煤气泄漏,直接影响生产安全。虽经电焊修补,但因阀体是铸铁材料,可焊性不好,往往是焊了旧裂纹又出现新
在仔细阅读了《中国学校体育》2009年第3期“立定三级跳远中的‘三跳’的技术要求”一文后,笔者认为,文中对立定三级跳远三跳的总结——“第一跳要‘弹’,第二跳要‘飞’,第
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
Under a large signal drive level,a frequency domain black box model of the nonlinear scattering function is introduced into power FETs and diodes.A time domain
To detect high frequency(HF) first-order sea echo spectra contaminated with ships,ionosphere interference, and other,a new characteristic-knowledge-aided detect