孙福生
,
曹春晓
金属学报
研究了Ｎｄ对Ｔｉ－５．５Ａｌ－４．５Ｓｎ－２Ｚｒ－ｌＭｏ－０．２５Ｓｉ－Ｎｄ耐热钛合金的组织、室温拉伸性能和热稳定性能的影响及其机．制结果表明，Ｎｄ可以细化组织，密化位错网亚晶界，改善室温拉伸强度和热稳定性能，Ｎｄ的强化机制主要由细晶强化（尤其是位错网亚晶界强化）和基体中Ｓｎ、Ｏ贫化引起的弱化的综合．
关键词:
耐热钛合金
,
strengthening
王瑞祥
,
谷南驹
,
殷福星
金属学报
本文用金相及电子显微分析研究了7CrSiMnMoV钢的马氏体形态及亚结构,并对不同形态的马氏体转化规律进行了分析。研究发现该钢冷却产生的马氏体有三种类型,包括晶界上优先产生的具有位错亚结构的宽大板条马氏体,晶内较细小的板条马氏体以及内部少量的孪晶马氏体片。基于上述结果,本工作试用短时等温淬火形成的下贝氏体来代替晶界马氏体,证明晶界组织形态对材料的强韧性有着很大的影响。
关键词:
钢
,
martensite
,
strengthening
SUN Dongli YANG Dezhuang LEI Tingquan CUI Yuexian Harbin Institute of Technology
,
Harbin
,
China Lecturer
,
Department of Metallic Materials and Technology
,
Harbin Institute of Technology
,
Harbin 150006
,
China
金属学报(英文版)
The fracture mechanism of deformation-aged Al-Li alloy was approached by investigating the influence of prior cold deformation on the precipitation kinetics as well as the behaviours of work hardening and fracture for Al-2.73Li alloy.The experimental results show that the work hardening rate and the strength are increased and the ductility is decreased by prior cold deformation.The decrease in ductility is mainly due to the cell dislocaton substructure distrib- uted inhomogeneously and the hardening of precipitate free zones at grain boundaries caused by prior cold deformation.The failure mode in the alloy is a mixed integranular and transgranular one.The tendency of intergranular fracture is intensified through the deformation-aging.The mechanisms of intergranular failure in the alloy are different under various deformation-aging treatments.
关键词:
Al-Li alloy
,
null
,
null
,
null
,
null
陈建军
,
李侃社
,
陈英红
,
牛红梅
,
闫兰英
高分子材料科学与工程
采用固相剪切碾磨方法成功制备了聚氯乙烯（PVC）-高岭土复合粉体,实现了高岭土的片层剥离和在PVC基体中的纳米分散及对PVC的同步增强增韧。通过X射线衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）表征了PVC-高岭土纳米复合材料的结构,研究了其力学性能。结果表明,30次碾磨,高岭土的特征衍射峰几乎消失,高岭土以约30 nm片层厚度均匀分散于PVC基体,径厚比超过10。与简单填充复合方法相比,固相剪切碾磨技术制备的PVC/高岭土纳米复合材料的力学性能有较大提高。在高岭土质量分数为4%时,断裂伸长率由87.3%提高到274.6%,提高了214.7%;拉伸强度由47.7 MPa提高到54.0 MPa。
关键词:
聚氯乙烯
,
高岭土
,
固相剪切纳米复合技术
,
磨盘碾磨
,
纳米复合材料
,
增强
,
增韧
WANG Ruixiang GU Nanju YIN Fuxing Hebei Institute of Technology
,
Tianjin
,
China
金属学报(英文版)
The morphology and substructure of martensites in 7CrSMnMoV steel were observed under optical or electron microscope,and martensitic transformation with its morphology was also analysed.In the normally quenched steel three types of martensites are found,including the wide lath one of dislocation substructure formed preferentially along grain boundaries,the thinner inner laths and the twinning martensite plate in interior of grain.Therefore,an at- tempt was made to substitute lower bainite,formed by short-term isothermal quenching.for intergranular martensite,it is believed that the morphology would be very influential to the stength-toughness of the steel.
关键词:
7CrSiMnMoV steel
,
null
,
null
CHEN Guosheng WU Bohua ZHOU Lecheng LI Yuqing Research Institute of Daye Steel Works
,
Huangshi
,
China Engineer
,
Research Institute of Daye Steel Works
,
Huangshi 435001
,
China
金属学报(英文版)
Because Nb accelerates the uniform distribution of MC phase and the grain refinement,as well as,increases the amount and stability of γ-phase,the tensile strength,ductility,stress rupture life and fatigue limit of Fe-30Ni-13Cr-1.2W-1.5Mo-2.5Ti-0.4AI superalloy at 650℃ can be improved with increase of Nb content up to 1.22 wt-%.The precipitation of small Laves phase particles dispersed along grain boundaries may be favourable to combined properties of the superalloy containing 1.22 wt-% Nb.It will be worsened only that the pre- cipitation of Laves phase particles'dispersed along grain boundaries may be favourable for combined properties of the superalloy containing 1.22 wt-% Nb.It will be worsened only that the precipitation of Laves phase is too more because of too high Nb content existhing.
关键词:
Nb
,
null
,
null
杨帆
,
贾悦欣
,
张然
,
陈兴刚
,
桑晓明
材料导报
介绍了聚合物/热塑性弹性体/纳米无机粒子三元复合材料的形态结构及增韧机理,分析了热塑性弹性体、纳米无机粒子、加工工艺、界面性能4个方面对聚合物/热塑性弹性体/纳米无机粒子三元复合材料形态和性能的影响.热塑性弹性体和纳米无机粒子对聚合物有协同增韧增强作用,加料顺序是形态结构的最主要影响因素,聚合物的力学性能非常依赖热塑性弹性体和纳米无机粒子在聚合物中的存在形态.最后,展望了该体系未来的研究方向.
关键词:
三元复合材料
,
增韧
,
增强
,
形态结构
张明福
,
张海亮
,
郭怀新
,
韩杰才
,
杨海
,
霍承松
,
黎建明
材料导报
蓝宝石窗罩在气动热效应作用下易产生破裂,使其结构/功能失效.提高蓝宝石高温强度可有效抑制其高温断裂行为.结合国内外研究成果,从蓝宝石高温失效机理、蓝宝石高温强度表征新方法和蓝宝石强化方法等方面,综合评述了蓝宝石强化研究领域的最新成果,其中重点介绍了蓝宝石强化的研究进展,最后指出了我国蓝宝石强化研究的努力方向.
关键词:
蓝宝石
,
失效机理
,
强化
,
进展
曾宪桃
,
任振华
玻璃钢/复合材料
针对FRP加固混凝土梁界面特性研究的众多问题,研究了FRP-混凝土界面粘结-滑移本构模型问题,界定了被加固混凝土梁体中介质与界面,找出了界面粘结剪应力的获取方法困难的原因,分析了界面滑移量的组成及刚体滑移以及界面粘结-滑移本构关系的参数及其适应性,对FRP加固混凝土梁FRP-混凝土界面的本构模型的有关问题进行了归纳和评价,并提出了FRP-混凝土界面特性研究的宽缺口梁试验法.
关键词:
纤维增强塑料
,
加固
,
混凝土梁
,
界面
,
本构模型
,
分析与评价
