S.Q. Zhou
,
W. Zhao
,
W.H. Xiong
,
Y.N. Zhou
,
null
,
null
,
null
,
null
金属学报(英文版)
Effect of Mo and Mo2C on the microstructure
and properties of Ti(C,N)-based cermets was investigated in this
article. The results have indicated that the weight percentage of Mo
from 5 to 10 can reduce Ti(C,N) grain diameter and thickness of the
rim, and Ti(C,N) grain can be wetted by Ni-Cu-Mo liquid so as to get
small contiguity of Ti(C,N) grain. In that way, the transverse
rupture strength of Ti(C,N)-based cermets has reached
1800—1900 MPa; the fracture toughness has been due to
16—18 MPa m1/2. But 15wt pct Mo was not more effective
on Ti(C,N)-based cermets, because the thickness of the rim becomes
larger. In the circumstance of Mo 2 C, 5 wt pct Mo 2 C was
good for microstructure and properties of Ti(C,N)-based cermets, but
11 wt pct Mo 2 C has resulted in larger contiguity of Ti(C,N)
grain and big Ti(C,N) grain diameter so as to reduce transverse
rupture strength and fracture toughness. So that, the effect of Mo
on Ti(C,N)-based cermets is better than Mo 2 C.
关键词:
Transverse rupture strength (TRS)
,
null
,
null
Surface & Coatings Technology
The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge ion-plating method. The influence of the rare-earth element yttrium on the TiN coating properties was studied. The results show that the adhesion of the coating to the substrate were evidently enhanced by adding a small amount (0.2 wt.%) of the rare-earth element yttrium, showing a critical load of about 390 g which is much higher than that (230 g) of the TiN coating/substrate. Investigation on the corrosion resistance of the Ti(Y)N coating and the TiN coating was performed in 0.5 N Na(2)SO(4) + 0.1 N H(2)SO(4) + 0.1 N NaCl corrosion media by means of an electrochemical potentiodynamic polarization. The Ti(Y)N coating exhibited much better corrosion resistance than the TiN coating, whose passivity maintaining current is about one order in magnitude smaller than that of the TiN coating. The Ti(Y)N coatings deposited on some HSS-based tools were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated tools is approximately 36% higher (on the pinion shape cutters) and about 50% higher (on punch side pin) compared to that of TiN coated. The Ti(Y)N coatings showed such excellent performance. It is attributed to that the transition area of Ti(Y)N/substrate consisted of three sublayers which revealed a gradual change of phase structure and composition, so that the adhesion of the coating/substrate was evidently enhanced. Moreover, Ti(Y)N coating showed a preferred orientation with (111) plane which is favorable to improve wear resistance and corrosion resistance of the coating. (C) 2010 Elsevier B.V. All rights reserved.
关键词:
Ti(Y)N coating;Adhesion;Wear resistance;Corrosion resistance;Phase;structure;Preferred orientation;tin coatings;coated tools;thin-films;deposition;steel;wear;yttrium;alloy;pvd
LIU Changqing YU Li YU Zhiming JIN Zhujing WU Weitao Corrosion Science Laboratory
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
China
金属学报(英文版)
The fine rnicrostrueture of the Y-modified ion plated Ti(Y)N coating/substrate steel A3 system has been examined by means of TEM and microdiffraction technique.It was revealed that the interface consists of 3 sublayers,i.e.α-Fe+Y_6Fe_(23),Ti+Y+FeTi and Ti_2N+YN +Ti_xN_y.The thicknesses of them are about 200,50 and 120 nm respectively.The phases in the transition area seem to have certain orientation relations.The mechanism of interface formation has also been discussed.
关键词:
Ti(Y)N coating
,
null
,
null
,
null
易艳玲
,
周丰群
,
拓飞
,
孔祥忠
原子核物理评论
doi:10.3969/j.issn.1007-4627.2006.02.009
用93Nb(n, 2n)92mNb和90Zr(n, 2n)89m+gZr截面比法测定中子能量, 以93Nb(n, 2n) 92mNb反应截面作中子注量标准, 用活化法测量了13.5-14.6 MeV中子引起的89Y(n, 2n) 88Y的反应截面值.由(13.5±0.3), (14.1±0.2), (14.6±0.3) MeV中子引起的89Y(n, 2n)88Y反应截面值分别为(759±42), (835±42)和 (958±53) mb.
关键词:
钇
,
快中子
,
反应截面
,
活化法
,
放射性活度
YANG Jilian ZHANC Baisheng DINC Yongfan China Institute of Atomic Engergy
,
Beijing
,
ChinaYANG Yingchang ZHANG Xiaodong Peking University
,
Beijing
,
ChinaPAN Shuming General Research Institute for Non-Ferrous Metals
,
Beijing
,
China associate professor
,
P.O.Box 275
,
Branch No.30
,
Beijing 102413
,
China
金属学报(英文版)
The N occupying sites and magnetic structures in R_2Fe_(17)N_x(R=Y,Dy,Nd)are de- termined by neutron diffraction.The effects of the site occupation of N on magnetic properties are discussed primarily.
关键词:
neutron diffraction
,
null
,
null
,
null
,
null
,
null
Physica B-Condensed Matter
The crystal structures, electronic structures, and optical properties of Y-doped gamma-Si3N4 were studied by using first-principles calculations based upon the density functional theory with Perdew-Burke-Enzerh (PBE) generalized gradient approximation (GGA). The band gap (E-g) of Y-doped gamma-Si3N4 is found to significantly decrease in comparison to that Of gamma-Si3N4. The calculated E-g suggests that gamma-Si3N4 doped with low Y content can be used in the window or absorption material of solar cell, while those doped with high Y concentrations can show metal behavior. The calculation of optical properties shows that the static dielectric constant of gamma-Si3N4 doped with Y is much higher than that of the undoped gamma-Si3N4, implying its special applications in electronics and optics. (C) 2008 Elsevier B.V. All rights reserved.
关键词:
electronic structures;optical property;doping;gamma-Si3N4;silicon-nitride;phase
Physical Review B
The theoretical elastic stiffness of Y(3)Si(5)N(9)O, the only Y-Si-O-N quaternary crystal that contains a framework of corner-sharing SiN(4) and/or SiON(3) tetrahedron in three dimensions, was investigated using the first-principles total energy calculations. The full set of second order elastic coefficients, polycrystalline bulk and shear moduli, and anisotropic elastic moduli were reported and further compared with those of Y(2)O(3) and beta-Si(3)N(4). The equation of state and compressibility of Y(3)Si(5)N(9)O were investigated at pressures up to 50 GPa. The crystal structure is stable up to 50 GPa and exhibits anisotropic compressibility under hydrostatic pressure. The relatively softer YN(6) and/or YN(5)O polyhedra are more prone to distort or deform than the SiN(4) and/or SiON(3) tetrahedra. Therefore, although the crystal structure of Y(3)Si(5)N(9)O contains a Si-N-O framework similar to that in beta-Si(3)N(4), it displays elastic stiffness between those of Y(2)O(3) and beta-Si(3)N(4).
关键词:
electronic-structure;optical-properties;silicon-nitride;constants;phases
杨继廉
,
张百生
,
丁永凡
,
杨应昌
,
张晓东
,
潘树明
金属学报
用中子衍射法测定了R_2Fe_(17)N_x(R=Y,Dy,Nd)中N的占位及磁结构,初步讨论了N的占位对磁性能的影响
关键词:
中子衍射
,
Curie temperature
,
permanent magnet
范永中
,
张淑娟
,
涂金伟
,
孙霞
,
刘芳
,
李明升
金属学报
doi:10.3724/SP.J.1037.2011.00292
分别在未施加偏压和施加-100V偏压条件下,利用磁控溅射技术在压气机叶片用1Cr11Ni2W2MoV热强不锈钢基体上沉积了Ti0.3Al0.7N和Ti0.3gAl0.55Si0.05Y0.01N硬质涂层.实验结果表明,施加偏压及Si和Y掺杂明显改变了涂层的相结构,提高了涂层致密度,施加-100 V偏压且添加Si和Y的涂层为非晶结构,表面更加均匀致密.950℃氧化实验表明:Ti0.39Al0.55Si0.05Y0.01N涂层表面形成极薄且致密的Al2O3保护性氧化膜,大大降低了氧化速率.施加-100 V偏压的(Ti,Al)N和(Ti,Al,Si,Y)N沉积态涂层与未施加偏压的相应涂层相比,硬度均降低,尤其是(Ti,Al,Si,Y)N涂层变化显著.经950℃热处理,施加偏压的(Ti,Al,Si,Y)N涂层硬度略有降低,这是由于形成了硬度较低的B4相,而未施加偏压的(Ti,Al,Si,Y)N涂层硬度显著提高,这归因于Bl相固溶体的分解.划痕测试结果表明,在实验载荷(50 N)下,所有涂层均未出现连续性的剥落.
关键词:
磁控溅射
,
(Ti,Al)N
,
Si和Y掺杂
,
抗氧化性能
,
硬度
,
结合力
李鹏
,
胡耀波
,
熊惟皓
,
林真
硬质合金
doi:10.3969/j.issn.1003-7292.2000.02.001
研究了稀土元素Y对Ti(C,N)基金属陶瓷微观组织和性能的影响.Y在Ti(C,N)基金属陶瓷中可以起到净化粘结相/硬质相界面的作用,并使其包覆层的厚度略有增加,从而使硬质相颗粒得到细化.当Y含量为0.8wt%时细化效果最明显,此时Ti(C,N)基金属陶瓷的抗弯强度和硬度值最大.
关键词:
稀土元素
,
Y
,
金属陶瓷
,
组织与性能
