共搜索到1282条信息，每页显示10条信息，共129页。用时：0小时0分0秒760毫秒
, the length transfer decreases, the location of the maximum shear stress is more away from the earth surface, and the maximum of shear stress and transfer length decrease. Key words: GFRP bar; steel bar; anti-floating anchor; shear stress; axial stress; numerical simulation; moderately weathered granite 锚杆具有单点受力小,施工简便,成本低等优点[1-3],因此,被越来越多地应用于解决建(构)筑物施工过程中的基坑支护,基础底板抗浮等问题.抗浮锚杆就是用于处理底板抗浮问题的一类锚杆.由于地下......
by the longitudinal wave velocity and the phenomenon shows obviously when the temperature increases. Key words: rock dynamics; split Hopkincon pressure bar; temperature pressure coupling; dynamic mechanical properties... parameters of granite samples 2.2 Test equipment The split Hopkinson pressure bar (SHPB) experimental system with a heating device used here is shown in Fig. 1. It mainly consists of a spindle punch......
of specimens with cracks of 5, 10 and 15 mm in depth as well as 1, 2, 3 and 4 in quantity. The improved split Hopkinson pressure bar (SHPB) testing system was used to carry out the impact loading test... Hopkinson pressure bar; crack；failure mode; energy dissipation; fractal theory 受地质作用影响,岩体内部往往产生许多裂隙和孔洞等缺陷,缺陷的存在弱化了岩石的物理力学性能,且缺陷尖端受应力集中作用极易起裂造成岩体失稳破坏.岩体发生变形破坏的实质是内部裂纹萌生,扩展和相互贯通的过程,由此可见,研究裂隙(节理)岩体的力学特性和破裂演......
promising one than those containing V andNb or containing V alone under the same pro-cessing conditions.From CCT curve of the steeland the cooling curve of the bar determined by sim-ulating the cooling rate in mill practice,the reasonwhy 40Si2MnMoV bar has excellent combinationof strength and ductility is clarified.关键词:......
: Ti60 Ti alloy; high-temperature titanium alloy; large section bar; microstructure; mechanical property 高温钛合金是一类设计使用温度在400 ℃以上的合金.目前,这类合金的最高使用温度为600 ℃,主要用于航空发动机轮盘和叶片等部位,以减轻发动机质量,提高推重比.目前,国内外有多种牌号的...些长条状a相之间,有细小的次生a相存在.由于大棒材心部冷速较慢,这些原本是细条状的a相发生了再结晶,变成细棒状(见图2(a?)).对应的热处理态组织中初生a相长成条状(见图2(b?)). 图2 K1大棒材不同位置取样的显微组织 Fig.2 Microstructures at different locations of K1 large-section bar......
; changes to <001> and <111>. The fracture mode changes from intergranular to a transgranular and shows a ductile laminate fracture mechanism. Key words: pure molybdenum bar; upset... rolled molybdenum sheets[J]. Mater Sci Eng A, 2008, 483/484: 79-83. [16] WARREN J. The 700 ℃ tensile behavior of Mo-0.5Ti-0.08Zr- 0.025C (TZM) extruded bar measured transverse and parallel to the billet......
Influence of Homogenization on the Microstructure and Tensile Properties of Extruded Mg-Zn-Zr-RE Alloy陶春虎,张少卿,鲁立奇摘 要:<正> The microstructure and tensile properties of the extruded Mg-Zn-Zr-RE alloy bars are studied.Theextruded bar without previous homogenization has the highest tensile strength,whereas the tensile strength of theextruded bar......
巴比妥与4-乙烯基吡啶分子印迹聚合物的设计及性能评价苏婷婷1,刘俊渤1,唐珊珊1,靳瑞发21. 吉林农业大学资源与环境学院2. 内蒙古赤峰学院化学化工学院摘 要:采用量子化学密度泛函理论(DFT)的M062X/6-31G(d,p)方法,模拟巴比妥(BAR)印迹分子与4-乙烯基吡啶(4-Vpy)功能单体的相互作用,确定BAR与4-Vpy的最佳印迹比例为1∶3.然后,在60℃乙腈中采用1∶3印迹比例合成巴比妥分子印迹聚合物(BAR-MIPs),并对BAR-MIPs微球形貌,印迹识别性能及选择性能等进行表征.结果表明,BARMIPs为微球形状,粒径在120390 nm之间;Scatchard分析表明,在研究的浓度范围内MIPs对模板BAR的结合位点是等价的,其离解平衡常数(Kd)与最大表观结合量(Qmax......
-section microstructures at edge position of bar after different procedures (Drawing direction is parallel to horizontal direction) 图1所示为不同工序后棒材纵截面边缘位置的光学显微组织.由图1可知,各工序后棒材纵截面的组织均由灰色的α相和黑色的β相组成,且α相均以拉长的变形晶粒...发生明显变化,但其硬度逐渐降低. 图3 热拔材经不同高温退火工艺后纵截面边缘位置的显微组织(水平方向为热拔方向) Fig. 3 Longitudinal-section microstructures at edge position of hot drawing bar after different high temperature annealing......
GH4169合金细晶棒材的连轧工艺及其组织与性能 陈国胜1,王庆增1,王资兴1,张玩良1,王世普1,刘丰军1,李伟1 (1.宝山钢铁股份有限公司,特钢事业部,上海,200940) 摘要:介绍了最新引进的我国第一套高合金钢连轧生产线及其所生产的GH4169合金φ20~φ55mm热轧细晶棒材的组织与性能.与传统的横列式轧机轧制的同规格棒材相比,该连轧工艺更易于获得晶粒均匀,适量δ相合理分布的细晶棒材;在所研究的规格范围内,晶粒度可稳定控制在10级左右,且工艺更稳定可控.因而,其轧棒具有更优良稳定的综合性能.同时产品尺寸精度和成材率均有较大幅度的提高. 关键词:GH4169合金; 热连轧棒材; 组织; 性能; GH4169 alloy; hot continuous-rolling bar; microstructure; property; [全文内容正在添加中] ......
