Y.S.Shi
,
S.C.Chen
,
X.L.Lu
,
S.H.Huang
金属学报(英文版)
How to directly fabricate metallic functional parts with selective laser sintering (SLS) process is a potential technique that scientists are researching. Existent problems during directly fabricating metal part by use of SIS are analyzed. For the sake of solving the problems, a new idea of adding self-propagating high-temperature synthesis (SHS) material into metallic powder material to form new type of SIS metallic powder material is put forward. This powder material can release controllable amount of heat during its interaction with the laser beam energy to reduce the requirement to laser power during directly sintering metallic part, to prolong the time of metallic liquid phase existing, and to improve the intensity and accuracy of SIS part. For this reason, SHS material's interaction with the CO2 laser beam energy is researched, which proves that CO2 laser beam energy may instantly ignite SHS reaction. On the basis of the above-mentioned researches, the effect of sintering the metal powder material mixing SHS material with CO2 laser is also researched,which shows: there is an optimal blending ratio of various material in the new metallic powder material. Under the optimal blending ratio and SIS process parameters, this new metallic powder material can indeed release amount of heat and SHS reaction may be controlled within the laser sintering. This research result makes it possible that the metallic part is directly sintered with small CO2 laser (less than 50W), which may greatly reduce the volume, cost and running expenditure of SIS machine, be propitious to application.
关键词:
selective laser sintering (SLS)
,
null
朱建新
,
陈梦君
,
于波
稀有金属材料与工程
将高温自蔓延反应原理应用于废旧阴极射线管(CRT)的处理,采用镁和氧化铁作为热剂,研究了废弃CRT玻璃高温自蔓延烧结合成玻璃陶瓷的可行性,考察了Fe_2O_3-Mg-CRT玻璃自蔓延体系的反应特性,探索了不同物料配比时燃烧波的传播规律.结果表明,系统维持自蔓延的CRT玻璃最大加入量为70%(质量分数,下同);燃烧波传播速率为0.5～6.5 mm/s,温度为1000～2000 ℃;两者均随CRT玻璃的加入量增加而呈线性降低.高温自蔓延合成样品主要构成相为玻璃陶瓷,可以实现铅的有效固定,处理后样品中铅的环境浸出率远小于相关国内和国际环境标准.
关键词:
废弃阴极射线管
,
高温自蔓延
,
含铅玻璃
,
资源化
张立
,
肖国庆
,
丁冬海
,
殷汉青
,
刘科燕
人工晶体学报
以金属Al粉和B2O3粉为原料,采用自蔓延高温合成法(SHS)制备AlB2-Al2O3复合粉体.采用X射线衍射仪、扫描电镜和能谱仪分析手段,对所制得的复合粉体进行了表征.研究了Al粉粒度(100目、300目和600目)对自蔓延高温合成方法制备AlB2-Al2O3复合粉体的燃烧学、相组成及微观结构的影响.结果表明:铝粉粒度越小,燃烧温度越高、燃烧波速度越快,复合粉体中AlB2相含量增加,实验测得600目铝粉反应的燃烧温度为2060K,燃烧波速度为2.08 mm/s.复合粉体以AlB2和Al2O3为主晶相,显微结构为数量较少、粒径约5μm的AlB2粉弥散分布于粒径约2 μm的Al2O3和Al的混合粉中.
关键词:
自蔓延高温合成
,
AlB2-Al2O3复合粉体
,
粒度
,
燃烧温度
,
燃烧波速
张钟威
,
肖国庆
,
付彦丽
,
侯爱东
兵器材料科学与工程
以Al和B为原料,探究利用化学炉自蔓延高温合成AlB2的新方法.根据热力学基本原理,对化学炉自蔓延高温合成AlB2的绝热燃烧温度进行数值计算,利用XRD和FESEM分别研究合成产物的物相组成和显微组织.结果表明:利用化学炉自蔓延高温合成技术可以成功制备AlB2;常温下Al-B体系的绝热燃烧温度Tad仅为1 261 K;只有当预热温度在1000K以上时,才可以实现自蔓延燃烧,燃烧温度T为2 053 K;此外,合成产物中还含有杂质相AlB12和残留的Al.
关键词:
二硼化铝
,
自蔓延高温合成
,
化学炉
