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将Fe-Cr-Ti-C系耐磨药芯焊丝采用钨极氩弧焊堆焊到低碳钢表面,分析熔覆层中的物相组成,研究熔覆层中硬质相的形态分布和生长机理,探究熔覆层的耐磨性及表面硬度等力学性能变化的原因. 结果表明,药芯堆焊焊丝中的合金元素的过渡系数很高,可原位合成(Fe,Cr)7C3和TiC硬质相,TiC优先依附外来界面行核、长大,共晶(Fe,Cr)7C3硬质相则依附于初生马氏体相和TiC形核生长,点状TiC硬质相(少数为条状和十字状)弥散分布于马氏体、残余奥氏体的基体中,与网状的(Fe,Cr)7C3耐磨框架组成复合硬质相,提高熔覆层的耐磨性. 相似文献
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本文应用文献[1]中提出的模糊模式识别模型,结合三峡区三斗坪址闪云斜长花岗岩风化程度分带指标,给出一种岩体风化程度分带的多指标结合评定方法. 相似文献
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Composite films were fabricated on A356 aluminum alloy by combined anodizing and rare earth deposition.The corrosion protection effect and corrosion behavior of the composite films in 3.5% NaCl solution were studied by electrochemical impedance spectroscopy(EIS).SEM observation indicated that the rare earth Ce film completely sealed the porous structure of the anodic film,and the compositefilms composed of anodic film and Ce film were compact and integrated.According to the characteristics of EIS,the EIS plots of the composite films at different immersion times were simulated using the equivalent circuits of Rsol(QceRce)(QaRa),Rsol(QceRce)(QpRp)(QbRb) andRsol(QpRp)(QbRb) models,respectively.The test results showed that the Ce film at the outer layer of the composite films had good protectioneffect at the initial stage of the immersion corrosion.It effectively helped the anodic film at the inner layer to prevent chloride irons frompenetrating the aluminum alloy matrix.After 18 days,the Ce film lost its anticorrosive property,and the anodic film took the leading role ofthe corrosion protection.When the corrosion time was up to 42 days,the aluminum matrix was not corroded yet.Thus,the higher protectiondegree of the composite films for A356 aluminum alloy was attributed to the synergism effects of anodic film and rare earth Ce film. 相似文献
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为了使水电工程监理评标规范化、科学化,基于BP人工神经网络理论,并结合监理评标工作的特点,建立了监理评标BP网络模型。考虑到BP模型的误差反向传播算法容易陷入局部极小点,以及会出现收敛速度慢等问题,对模型训练的计算方法进行了改进。将所建立的评标模型应用于实际,并对模型的学习能力进行了检验,结果表明,该模型精度较高,具有较好的适用性。 相似文献
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通过四年来丽雪公司成品检验数据,结合实际工作经验,加上相关理论指导,对马铃薯淀粉水分、白度、灰分、二氧化硫、粘度、电导率、斑点等七项指标的影响因素进行粗浅分析,旨在更好控制马铃薯淀粉产品理化指标,增强顾客满意度,提高市场占有率。 相似文献