MI Guofa
,
NAN Hongyan
,
LIU Yanlei
,
ZHANG Bin
,
ZHANG Hong
,
SONG Guoxiang
钢铁研究学报(英文版)
Speed increase and heavy-haul of the railway freight car are the effective measures to raise the transport ability of railway, and they have been the new trend for railway freight car development. The increase of speed and axle load will lead to the increase of wheel-rail contact stress, which will make a great change of stress distribution in the whole wheel rim. Goodier equation was employed to analyze the stress state around inclusion and cavity. In the operation of wheel-rail contact stress, stress concentration occurred in the pole of Al2O3 spherical inclusion, while it appeared on the equator of cavity. The critical inclusion sizes of 25t axle load freight car wheel at different velocities, a certain distance away from the tread, were calculated by Murakami equation. By contrast the inclusion state in cast-steel wheel and rolled-steel wheel, the inclusion character in cast-steel wheel determined that it has much more excellent crack resistance than that of rolled-steel wheel. In the meantime, in order to reduce the probability of rim crack, some suggestions were put forward.
关键词:
heavy-haul;contact stress;critical inclusion size;rim crack
MI Guofa
,
LI Hongyu
,
LIU Xiangyu
,
WANG Kuangfei
钢铁研究学报(英文版)
The porous superalloy materials with hollow spherical pores were fabricated by using metal powder sintering process. The scanning electron microscope (SEM) observation was applied to the test samples and it revealed that the pores of the porous material exhibited a uniform distribution and the apertures were of same size in principle. The sintering necks appeared between adjacent particles on metal skeleton after sintering. The mechanical properties of the test samples were analyzed and the result showed that this kind of materials possessed excellent energy absorption capability, and the compression resistance decreased with increasing the porosity and aperture.
关键词:
porous superalloy material;metal powder sintering;hollow spherical pore;oriented linear pore
MI Guofa
,
LIU Xiangyu
,
WANG Kuangfei
,
FU Hengzhi
钢铁研究学报(英文版)
The numerical simulation technique was applied to the casting process of a valvetype part. The moldfilling and solidification stages of the casting were numerically analyzed. The filling behavior, solidification sequence, and thermal stress distribution were reproduced and the possible defects, such as cold shut and shrinkage, were predicted. Based on the simulation result, the doublegating system was replaced by a singlegating system. Meanwhile, the chills were used to regulate the solidification sequence of casting. To eliminate the cracks in the casting, the sand core was converted into a canulate one. By modifying the original process, the defects were eliminated and the casting with good quality was obtained.
关键词:
cast steel;valvetype part;numerical simulation;process modification
李尊
,
吴谨
,
刘劲
,
吴秋红
液晶与显示
doi:10.3788/YJYXS20153002.0353
在经典 Criminisi 图像修复算法框架的基础上，针对优先权可靠性低和全局搜索最佳模板效率低、错误匹配率大的缺点进行改进。改进的算法为基于萤火虫算法(FA)的快速 Criminisi 图像修复算法。首先从数学的角度引入正规化函数至置信度，以此提升优先权计算的可靠性；然后引入 FA 到最佳模板的搜索与填充中，能够有效地将全局搜索与局部搜索有效地结合，鲁棒性较高，提高效率且错误匹配率低。实验结果表明：采用本文的改进算法能在保证修复质量的基础上降低时耗，提高效率。
关键词:
Criminisi算法
,
优先权
,
最佳匹配模板
,
FA
周筠
,
吴勇生
,
李如燕
,
孙可伟
,
王敏
硅酸盐通报
以粉煤灰(FA)、铸造旧砂热法再生粉尘(DHRS)为原料,在水玻璃型碱性激发液的激发作用下研究制备了DHRS-FA地质聚合物材料(铸造旧砂热法再生粉尘-粉煤灰基地质聚合物材料).为了探讨不同的养护工艺对DHRS-FA地质聚合物材料强度的影响,研究了自然养护、湿养养护、高温蒸养(40℃、60℃、80℃)养护对地质聚合物强度的影响.结果表明:试样在高温养护工艺下,其早期抗压强度形成较快,且优于自然养护和湿养养护工艺下试样形成的抗压强度;试样在高温养护工艺下,中期和后期抗压强度趋于自然养护试样的抗压强度;而湿养条件下养护的试样抗压强度最差.
关键词:
粉煤灰
,
铸造旧砂热法再生粉尘
,
地质聚合物材料
,
高温养护工艺
邓海文
,
檀柏梅
,
张燕
,
高宝红
,
王辰伟
,
顾张冰
功能材料
doi:10.3969/j.issn.1001-9731.2016.06.038
在化学机械抛光(CMP)过程中,加入苯并三氮唑(BTA)抑制 Cu 界面和布线条的腐蚀.但同时,会与Cu发生化学反应生成的Cu-BTA钝化膜是CMP后主要的清洗对象之一.采用FA/OⅡ型螯合剂作为清洗液的主要成分,采用接触角测试仪及原子力显微镜来表征BTA的去除效果.通过改变 FA/OⅡ型螯合剂的浓度完成一系列对比实验,确定最佳的清洗效果.通过对比实验得知,当清洗液中螯合剂的浓度为1．50×10－4~200×10－4时,此时清洗液的pH 值＞10,能有效去除Cu-BTA 钝化膜以及其它残留的有机物,接触角下降到29°,表面的粗糙度较低.
关键词:
CMP后清洗
,
FA/OⅡ螯合剂
,
Cu-BTA钝化膜
,
接触角
,
粗糙度
李逍霄
,
张敏
,
李喆
,
郑丹星
,
董丽
工程热物理学报
根据前人对有机Rankine循环和吸收式制冷循环的研究,本文选出了一组有潜力的吸收式动力循环工质R245fa+DMF.利用外循环可视汽液相平衡(VLE)测定装置,本文测定了温度293.15～353.15K,压力15～700 kPa条件下R245fa+DMF体系的VLE数据.利用逸度系数法中的PR、SRK状态方程,活度系数法中的NRTL、Wilson模型,本文对体系的VLE数据进行了关联.偏差评价表明,NRTL模型能够较好描述该体系在实验温度压力下的VLE数据.从p-x图上可以看出,该体系呈现对Raoult定律较强的负偏差,显示R245fa和DMF具有很好的亲和性.因此,R245fa+DMF的组合具有成为吸收式动力循环工质对的潜力.
关键词:
汽液相平衡
,
R245fa
,
DMF
,
NRTL模型
,
吸收式动力循环
张丽丽
,
王波
,
张士杰
,
肖云汉
工程热物理学报
在透平冷却空气量估算的基础上,建立了透平逐级计算、考虑IGV角度对压气机特性曲线影响的PG9351FA燃机变工况模型.针对改烧合成气带来的压气机喘振、通流匹配等问题,分析了关小IGV角度、增大透平通流面积、降低燃气轮机T3温度等几种不同的通流调整措施对燃气轮机最大出力、压气机喘振裕度以及燃气轮机整体性能的影响,提出了一种同时增大透平通流面积和关小IGV角度的PG9351FA燃气轮机通流综合调整方案.
关键词:
燃气轮机
,
合成气
,
通流调整
胡喜兰
,
施鹏飞
,
姜琴
,
王大奇
人工晶体学报
用醋酸铜、苯妥英(即5,5-二苯基-2,2咪唑烷酮,简称Hpht)与糠胺(2-furfurylamine,简称fa)反应,得到一种新的配合物[Cu(pht)2 (fa)2] (H2O)2,通过红外光谱、元素分析以及Ⅹ-射线单晶衍射的方法,对配合物的结构进行了表征.该晶体属三斜晶系,Pt空间群,晶胞参数:a =0.9878(2) nm,b=1.0068(2) nm,c=1.0640(3) nm,α=78.664(3)°,β=75.490(2)°,γ=72.050(3)°,Z=1,Dc=1.368 mg·m-3,R1=0.0986,ωR2 =0.2191.每个标题配合物分子中Cu(Ⅱ)离子与2个Hphi配体、2个fa配体的4个氮原子形成四方形构型,同时利用琼脂扩散法测试了配合物、苯妥英和铜盐对大肠杆菌(Escherichia Coli),金黄色葡萄球菌(Staphylococcus Aureus),枯草芽孢杆菌(Bacillus Subtilis)的抑菌活性,结果表明,它们对3种致病细菌均有一定的抑制作用.
关键词:
苯妥英
,
配合物
,
合成
,
晶体结构
