李谷松
,
丁炳哲
,
苗卫方
,
叶荔蕾
,
郭建亭
金属学报
用球磨机分别对Ｎｉ－５０ａｔ．－％Ａｌ和Ｎｉ－２５ａｔ．－％Ａｌ混合粉末进行机械合金化，并对Ｎｉ_３Ａｌ预合金粉末进行高能球磨，观察了粉末的金相组织，测定了粉末的硬度、平均直径和晶粒尺寸，并作了ＸＲＤ物相分析结果表明，经３ｈ研磨，Ｎｉ－５０ａｔ．－％Ａｌ混合粉末变成ＮｉＡｌ金属间化合物，其晶粒直径约５ｎｍ；经５ｈ机械球磨，Ｎｉ－２５ａｔ．－％Ａｌ混合粉末成为无序的亚稳定Ｎｉ固溶体，而Ｎｉ_３Ａｌ预合金粉末由Ｌｌ_２型长程有序金属间化合物转变为ｆｃｃ无序固溶体；球磨更长时间，则形成纳米晶．
关键词:
金属间化合物
,
mechanical alloying
,
nanocrystalline structure
,
Ni
,
Al
,
Ni_3Al
,
NiAl
吴玉琨
,
黄建宇
,
何安强
,
胡魁毅
,
孟祥敏
金属学报
机械合金化可使室温下几乎不互溶体系Cu_xFe_(100-x)形成过饱和固溶体fcc相区的固溶度范围扩展到x>35 at-％.对Cu_(40)Fe_(60)进行的高分辨电镜观察表明:球磨3h后bcc相与fcc相之间存在N-W关系,即<001>α∥ <110>γ。,<110>α∥<111>γ,表明在球磨的过程中发生了逆马氏体相变,fcc相区的扩展与此密切相关.球磨60h后形成了尺寸比较均匀的纳米晶结构.高分辨电镜同时观察到了粒子的破断、细化以及层状结构的形成
关键词:
Cu-Fe系
,
mechanical alloying
,
high resolution electron microscope
,
supersaturated solid solution
,
martensitic transformation
吕铮
,
卢晨阳
,
张守辉
,
谢锐
,
刘春明
金属学报
doi:10.3724/SP.J.1037.2012.00072
采用机械合金化和热等静压技术制备纳米结构14Cr-ODS铁素体钢, 利用SEM, XRD和EDS等手段分析了机械合金化过程中粉末形态和结构的变化以及合金元素的固溶情况, 通过TEM研究了14Cr-ODS铁素体钢的微观结构及其在短时高温下的稳定性. 结果表明, 元素粉末经机械合金化过程中发生反复的冷焊和断裂导致粉末尺寸先增加(0--2 h)后下降 (2-70 h), 晶粒尺寸随球磨时间的增加而减小, 同时Cr, W和Y2O3等固溶入Fe基体中. 纳米结构14Cr-ODS钢中存在3种析出相: 极高密度的、尺寸在几个纳米的富Y-Ti-O团簇, 少量Y2Ti2O7析出相和块状富Cr-Ti相. 经1250 ℃, 8 h短时高温热处理后, 纳米团簇显示出了良好的稳定性, Y2Ti2O7相的密度增加.
关键词:
ODS钢
,
mechanical alloying
,
hot isostatic pressing
,
Y-Ti-O-rich cluster
,
stability
张来昌
,
沈智奇
,
徐坚
金属学报
采用Sn替代Ti50Ni22Cu18Al4Si4B2合金中的Si和B, 形成Ti50Ni22Cu18Al4Snx(Si0.67B0.33)6-x(x=0,3, 6)系列合金. 所有的预制合金碎屑经过机械研磨均发生非晶化转变. 随着合金中Sn含量的增加, 球磨产物中转变未尽的晶体相-Ti含量减少. 由Sn完全替代Si和B的Ti50Ni22Cu18Al4Sn6合金, 机械研磨可形成与熔体急冷几乎相同的单一均匀非晶相, 过冷液态温度区间可达到66 K.
关键词:
钛合金
,
mechanical alloying
,
amorphous alloy
LIU Zhiguang+ *
,
GUO Jianting *
,
LI Gusong+
,
HU Zhuangqi++State Key Lab. of RSA
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang
,
China * Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang
,
China
金属学报(英文版)
Mechanical alloying (MA) of Ni50Al45Ti5 (atomic per cent) is studied by in situ thermal analyses, XRD and metallography. The results showed that the alloying process of Ni50Al45Ti5 is similar to that of Ni50Al50. The addition of 5 at.%Ti prolongs the milling time of alloy prior to the explosive reaction in the alloy. The final product is nanocrystalline β-phase NiAl(Ti) (B2 structure). The addition of 5 at.% Ti shows little effect on the lattice parameter of β-phase.
关键词:
mechanical alloying
,
null
,
null
,
null
LIANG Guoxian WANG Erde HUO Wencan Harbin Institute of Technology
,
Harbin
,
China Post Box 435
,
Harbin Institute of Technology
,
Harbin 150006
,
China
金属学报(英文版)
Ni_(100-x)Mo_x(x=20,30,38)alloys have been synthesized by mechanical alloying.The structure evolution of powders in mechanical alloying process has been monitored by X-ray diffraction,scanning electron microscopy and transmission electron microscopy analyses.The results show that the Ni_(62)Mo_(38)sample becomes partially amorphous after high energy ball milling,while the Ni_(80)Mo_(20)and Ni_(70)Mo_(30)become non-equilibrium nanocrystals.
关键词:
mechanical alloying
,
null
,
null
,
null
Y.Z. Yang
,
X.J. Bai
,
T.C. Kuang
金属学报(英文版)
The structure of bcc-Fe80 Cu2o solid solution produced by mechanical alloying of theelemental bcc-Fe and fcc-Cu powders has been studied using X-ray diffraction and theextended X-ray absorption fine structure (EXAFS) techniques. The disappearance ofelemental Fe and Cu X-ray diffraction (XRD) peaks and the presence of bcc structuralXRD peaks illustrate the formation of a nanocrystalline single-phase bcc-Fe80 Gu20solid solution. From the EXAFS results, the clear observation of Cu atoms taking onbcc coordination in the solid solution and Fe atoms remaining bcc structure furtherverifies the reality of atomic alloying between Fe and Cu atoms and the lattice changeof Cu from fcc to bcc. However, the supersaturated bcc solid solution is not chemicallyuniform, i.e., some regions are rich in Fe atoms and other regions rich in Cu atoms.
关键词:
mechanical alloying
,
null
,
null
,
null
