X. J. Sun
,
J. L. Gu
,
B. Z. Bai
,
B. Dai and N. P. Chen (Department of Materials Science and Engineering
,
Tsinghua University
,
Beijing 100084
,
China
金属学报(英文版)
This paper reviews various fabrication methods of ultrafine grained materials and their limitations briefly, and examines the possibility to produce ultrafine grained titanium alloy by compressive deformation preliminarily. It has been shown that submicrongrained TC11 alloy can be obtained by compressive deformation below 725°C. During microstructure refinement, dynamic recrystallization occurs only in α phases, and β phases undergo a process of precipitation and growth. Compared with the situation of static annealing, deformation can not only enhance the precipitation and growth of β phases but also change the morphology of βprecipitates.
关键词:
TC11 alloy
,
null
,
null
,
null
赖红伟
,
曹宏梅
,
董顺福
,
韩丽琴
,
陆钊
,
董树国
,
贾骐羽
应用化学
doi:10.3724/SP.J.1095.2014.30321
研究了阿莫西林对B-Z振荡反应的影响,结果表明,阿莫西林的加入明显地改变了振荡体系的周期和振幅,即对振荡体系产生扰动,且阿莫西林的浓度分别在1.5×10-5～2.4×10-3mol/L和4.7 × 10-5～4.8×10-3 mol/L范围内与振荡周期改变值Δt和振幅改变值ΔA均呈良好的线性关系,相关系数分别为0.9822和0.9846,同时结合FKN机理,初步探讨了阿莫西林扰动B-Z振荡反应的机理.
关键词:
阿莫西林
,
化学振荡
,
指纹图谱
,
B-Z振荡
Fatigue & Fracture of Engineering Materials & Structures
Fatigue crack growth behavior in welded joints subjected to elastic-plastic shock waves was investigated using three-point-bend specimens. The results indicate that the fatigue crack growth rate is reduced in the affected region of elastic or plastic waves. The travel of a plastic stress wave reaches 10 to 13 mm depth, but the hardness in this region is not increased although the lattice distortion is high. The crack path morphologies were observed, and reasons for a decrease in crack growth rate are presented.
关键词:
Zhijian LIU
,
Zhiyou LI
,
Wei DUAN
,
Xuanhui QU
,
Baiyun HUANG
,
Siqi ZHANG
材料科学技术（英文）
A LI-B alloy has been prepared using a pretreated amorphous B powder and pure Li ingot as starting materials by continually slow addition of B powder and intensified stirring in the process of melting. The microstructure and the discharge characteristic of the materials have been investigated. Results show that the problem of temperature control in synthesis would be modified by means of continual addition of B powder, the Li7B6 would be more finery distributed in the metal Li by means of intensified stirring. The discharge characteristic of the Li-B alloy using amorphous B as starting materials is almost the same with that of using crystalline B.
关键词:
李虎
,
王作成
,
薛长深
,
庄栋栋
,
王晓
,
张思勋
材料热处理学报
为了研究钢中合金元素Nb、B、Ni对低合金高强度H型钢抗层状撕裂能力(Z向性能)的影响,设计了对照试验,通过常温下拉力试验,对其力学性能尤其是断面收缩率进行了测试,使用XRD、SEM、TEM以及EDS对其组织和成分进行了分析.结果表明:微合金元素Nb、B和微量元素Ni对钢材的Z向性能产生了明显的不良影响,含有Nb、B和Ni,经过钢包精炼的Q345E钢的Z向性能显著低于不含Nb、B和Ni,未经钢包精炼且含有较多夹杂物的Q345B钢.其原因主要在于Nb、B、Ni的存在阻碍了钢材变形过程中位错在晶界和晶内的移动.
关键词:
低合金高强度钢
,
Z向性能
,
合金元素
,
夹杂物
,
阻碍位错
王晓旭
,
陈利
材料工程
doi:10.3969/j.issn.1001-4381.2011.11.001
通过单根Z-pin从复合材料层合板中拔出的试验方法,测试了Z-pin的拔出强度,计算了Z-pin的临界埋入深度,并引入抗拉强度利用率概念来表征Z-pin的抗拉强度在拔出过程中的利用程度.结果表明,直径0.50mm和0.28mm的Z-pin临界埋入深度分别约为5.1mm和3.1mm.当Z-pin的埋入深度小于临界埋入深度时,Z-pin从层板中拔出；Z-pin拔出强度与埋入深度成正比,与Z-pin的直径成反比；当Z-pin的埋入深度大于临界埋入深度时,Z-pin发生断裂,Z-pin的抗拉强度利用率达到100％.最后提出了提高抗拉强度利用率的建议.
关键词:
Z-pin
,
拔出强度
,
复合材料
,
拔出试验
,
抗拉强度
王晓旭
,
陈利
航空材料学报
doi:10.3969/j.issn.1005-5053.2011.4.017
通过三种复合材料Z-pin的轴向压缩试验,观察了各Z-pin的压缩行为,分析了三种复合材料Z-pin在不同长度时的极限应力及其失效形式.结果表明,直径为0.50mm的碳纤维Z-pin的压缩性能最好,其各长度Z-pin所能承担的极限应力都较大.直径0.28mm的碳纤维Z-pin易发生失稳现象,芳纶纤维Z-pin在压缩力的作用下,接触端容易受到破坏.两种碳纤维Z-pin临界应力的理论值与试验值吻合较好,但芳纶纤维Z-pin的临界应力的试验值比理论值偏低.
关键词:
Z-pin
,
复合材料
,
压缩试验
,
临界应力
