Y.L. Yang
,
C.S. Liu
,
F.J. Sun
,
D. Zhang
金属学报(英文版)
CW-CO2 laser nitriding technique was applied to improve the properties (such as aging property and the core loss) of grain oriented silicon steel. The samples were nitrided with regular space. Laser power density and scanning speed were chosen as 7.8×105W·cm-2 and 100mm·min-1. By some laser irradiation, Fe4N and Fe3N were formed in the nitrided zone. The nitrided samples were annealed at the temperatures ranged from 100 to 900°C. The core loss of some interested samples was tested. The results show that the core loss of the nitrided samples with different thickness of 0.23 and 0.30mm decreased by 14.9% and 9.4% respectively, and the aging property were improved up to 800°C. The mechanism of laser nitriding to improve the properties of grain oriented silicon steel is discussed.
关键词:
laser nitriding
,
null
,
null
F.J. Shan
,
C.S. Liu
,
S.H. Wang
,
G.C. Qi
金属学报(英文版)
The corrosion behavior of hot dip galvanized steel
pretreated with bis-[triethoxy-\linebreak\noindent silylpropyl]
tetrasulfide (BTESPT) modified with alumina particles was studied.
The corrosion resistance of the passiving films was evaluated by
Tafel polarization curve and electrochemical impedance spectroscopy.
The films formed on the galvanized steel substrate were
characterized by Fourier transform infrared spectroscopy and energy
dispersive X-ray spectrometry. The surface morphology of the treated
hot dip galvanized steel samples was observed by Field Emission
Scanning Electron Microscope. The results show that the
pretreatments on the basis of silane films modified with nanoalumina
particles have reduced both anodic and cathodic current densities,
and increased total impedance in the measured frequency,
consequently, improving corrosion protection for hot dip galvanized
steel during immersion in NaCl solutions compared to chromate films
and silane films.
关键词:
Bis-sulfursilane
,
null
,
null
,
null
,
null
S.H. Wang
,
C.S. Liu
,
F.J.Shan
,
G.C. Qi
金属学报(英文版)
The amino-tri-(methylenephosphonic acid) layers were adsorbed on the surface of AA6061 aluminum alloy for improving the lacquer adhesion and corrosion inhibition as a substitute for chromate coatings. The surface structure and characteristic of the amino-tri-(methylenephosphonic acid) layers on AA6061 aluminum alloy were investigated by means of XPS and ATR-FTIR analysis. The analyzed results showed that the amino-tri-(methylenephosphonic acid) adsorption layers adsorb on the surface of aluminium alloy $via$ acid-base interaction in a bi-dentate conformation. After the amino-tri-(methylenephosphonic acid) layers were coated with epoxy resin, the layers showed good adhesive strength and favorable corrosion resistance in contrast to
chromate coatings.
关键词:
Amino-tri-(methylenephosphonic acid)Layer
,
null
,
null
,
null
陈树东
,
项建明
,
王晓翠
,
洪笑
硅酸盐通报
以Ca(OH)2、SiO2、Fe2O3、Al2O3化学纯为原料,分别掺入不同质量分数的Ba(OH)2制备不同矿物相组成的熟料相,运用化学分析、XRD、SEM、水化热测试方法,研究掺Ba(OH)2后熟料相中硅酸三钙-硅酸二钙(C3S-C2S)混合相组成、晶型、新相生成的变化规律.结果表明:Ba(OH)2一定程度上削弱C3S形成,且稳定β-C2S形成效应明显,矿物相体系中α'-C2S、α-C2S量减少并转换为β-C2S,掺量大于2.5％后有新相Ba0.48 Ca1.52SiO4形成;Ba(OH)2掺入促使矿物相中C2S相明显增多,晶粒整体尺寸变小,边界变圆润;随Ba(OH)2掺量递增,熟料样的水化速率呈持续减小的趋势变化.
关键词:
C3S相
,
β-C2S
,
水化速率
,
水化
姜奉华
,
徐德龙
硅酸盐通报
doi:10.3969/j.issn.1001-1625.2004.06.006
通过研究Q相与C2S和Q相与C4AF的共存条件,构造Q相-C2S-C4AF水泥系统,对此系统水泥形成条件进行研究.研究表明:Q相与C2S和Q相与C4AF能够共存,可以组成Q相-C2S-C4AF-C12A7水泥系统.在Q相-C2S-C4AF-C12A7水泥系统中,Q相在1270℃开始生成,随着温度的升高,Q相的生成量逐渐增大;采用V2O5对β-C2S具有较好的稳定作用.随着C4AF量的增加,Q相的量也在增加,同时,烧成温度降低.
关键词:
Q相
,
Q相-C2S-C4AF水泥
,
形成条件
,
抗压强度
管宗甫
硅酸盐通报
用工业原料在不同温度预合成C2S(2CaOSiO2)为主要矿物的前导物,并以该前导物为基础,补入适量的钙,在不同温度下二次烧成水泥熟料.结果显示:采用1250℃、1300℃和1350℃预合成的C2S前导物配料二次烧方法,有利于熟料在低温下烧成,在1350℃左右实验熟料样品中游离氧化钙即可小于1.0％.相应C3S在熟料体系中的表观形成活化能相比不同配料烧成的对比组明显降低,而不同温度制备的前导物配料,C3S在熟料体系中的形成活化能相差无几.
关键词:
C2S前导物
,
二次烧成
,
水泥熟料
,
硅酸三钙
,
活化能
