钢坯氧化烧损影响因素试验研究

通过在实验室进行不同加热温度、不同加热气氛对钢坯试样氧化烧损影响研究试验，找出造成钢坯氧化烧损加剧的温度区间及适宜加热气氛，为现场的生产操作提供参考，降低钢坯的氧化烧损率。     

钢坯加热过程中氧化烧损的因素及其控制

通过对铜坯氧化烧损情况的调查，分析了钢坯加热过程中氧化烧损的主要因素，并有针对性地提出控制措施，使钢坯氧化烧损率得以降低。     

降低加热炉板坯氧化烧损的技术分析与对策

本文针对板材公司步进梁式加热炉板坯加热氧化烧损状况，分析、讨论了影响板坯氧化烧损诸因素，使板坯的氧化烧损得到了有效控制。加热炉的使用周期从原来的２个月延长到６个月。     

宝钢热轧加热炉氧化烧损计算数模的建立和实施

采用计算机在线氧化烧损数模来计算宝钢热轧加热炉钢坯氧化烧损，比原采用人工称量的办法既省力又精确，同时还优化了加热炉的燃烧控制，对减少氧化烧损和节约能源起到一定作用。     

富氧燃烧气氛下钢坯氧化烧损影响因素试验研究

通过恒温动力学试验，模拟富氧燃烧气氛，研究不同工况对钢坯氧化烧损的影响。得出结论，钢坯表面温度和助燃空气富氧浓度越高，钢坯氧化烧损越严重；烟气中H₂O含量是影响钢坯氧化烧损的主要因素。     

降低窄带钢加热炉氧化烧损工艺实践

针对宣钢热带车间加热炉氧化烧损高的问题,分析了钢材表面的氧化烧损形成机理、影响烧损的因素.通过优化加热制度、控制空燃比、优化待轧保温制度、改进加热炉结构,有效地降低了氧化烧损.     

降低棒材加热炉氧化烧损改进措施

分析了棒材加热炉炉内氧化烧损大产生的原因，针对其原因采取相应的改进措施，并进行了实施，从而减少了炉内钢坯的氧化烧损，取得了一定经济效益。     

降低板坯氧化烧损的探讨

氧化烧损是金属热加工中影响技术经济指标的一大重要因素。本文针对热轧板厂步进梁式加热炉氧代烧损状况 ,分析、讨论了影响板坯氧化烧损的诸因素 ,提出了有效的技术措施 ,使板坯氧化烧损得到了有力的控制。     

减少连铸板坯氧化烧损的对策

介绍了减少中厚板厂连铸板坯氧化烧损的方法及其在重钢中板厂的应用情况，分析了连铸板坯氧化烧损偏高的原因，提出了相应的改进办法。     

加热炉氧化烧损严重的技术分析

通过对氧化烧损率的测定及加热炉的热工分析,从不同方面阐述了造成加热炉氧化烧损严重的原因,提出了降低氧化烧损的具体措施.     

表面质量对取向硅钢铁损的影响

取向硅钢的表面质量(包括底层质量,内氧化层以及表面氧化)对铁损会有明显的影响,但各因素对铁损的影响程度和影响机理仍不清楚。通过轻酸洗去掉外氧化层比较酸洗前后铁损变化,酸洗去掉底层比较去掉底层前后铁损的变化,抛光去掉底层及内氧化层比较抛光前后铁损的变化来研究表面质量各因素对铁损的影响。发现表面氧化对铁损没有明显影响,内氧化层对铁损影响最大。用扫描电镜分析内氧化层的形貌及成份发现内氧化层是镁橄榄石和尖晶石的离散质点。内氧化层通过其对180°畴壁移动的钉扎增加铁损,底层通过增加90°闭合畴的体积分数增加铁损。     

降低08Al板坯高温氧化烧损

为了降低08Al板坯氧化烧损,采用模拟08Al板坯高温氧化烧损过程,研究08Al的微观氧化机理和特征以及不同加热条件(气氛组成和温度)对其氧化动力学的影响。结果表明,氧化烧损随p(O_2)的降低而显著降低,在氧气体积分数小于0.1%中的烧损比氧气体积分数4%(工况)中的至少降低了70%以上;在氧气体积分数为4%条件下,温度从1 250降至1 200℃,08Al烧损减少了12%,相比之下,降低p(O_2)比降低温度能更有效地减少钢坯的氧化烧损。     

富氧气氛下高温合金氧化特征及机理

 对GH169、GH202、GH642和GH586高温合金在900~1 200 ℃富氧气氛中的氧化行为等进行了系统研究。发现高温合金在富氧中表现出与空气完全不同的氧化特征,即从氧化增重转变成氧化失重,且随温度增加而明显。同时发现高温合金GH202在空气和富氧下氧化增重和失重都较同类合金低,高纯富氧下表现更为突出。并结合SEM、EDS等对合金在富氧中氧化物种类和形成机理等进行了分析。     

降低钢坯氧化烧损的探索与实践

分析了安钢一轧厂加热炉内氧化烧损的生成及影响因素,采取改进措施后氧化烧损降低,效果良好.     

加热炉氧化烧损原因与对策分析

就加热炉加热过程中氧化铁皮的形成机理及影响因素进行了论述，并介绍了目前国内解决氧化烧损所采取的一些有益的方法。     

高速钢的氧化失重回归方程

在实验数据的基础上,对Ｗ９、Ｍ２、Ｍ２Ａ１、Ｄ６０６４种高速钢在空气中加热时的氧化失重进行回归分析,得到回归方程,并讨论了加热温度和时间对４种高速钢氧化失重的影响。     

Oxidative susceptibility of low density lipoprotein subfractions is related to their ubiquinol-10 and alpha-tocopherol content

The conjugated polyene fatty acid parinaric acid (PnA) undergoes a stoichiometric loss in fluorescence upon oxidation and can be used to directly monitor peroxidative stress within lipid environments. We evaluated the course of potentially atherogenic oxidative changes in low density lipoproteins (LDL) by monitoring the oxidation of PnA following its incorporation into buoyant (p = 1.026-1.032 g/ml) and dense (p = 1.040-1.054 g/ml) LDL subfractions. Copper-induced oxidation of LDL-associated PnA exhibited an initial lag phase followed by an increased rate of loss until depletion. Increased PnA oxidation occurred immediately after the antioxidants ubiquinol-10 and alpha-tocopherol were consumed but before there were marked elevations in conjugated dienes. Despite differences in sensitivity to early oxidation events, PnA oxidation and conjugated diene lag times were correlated (r = 0.582; P = 0.03), and both indicated a greater susceptibility of dense than buoyant LDL in accordance with previous reports. The greater susceptibility of PnA in dense LDL was attributed to reduced levels of ubiquinol-10 and alpha-tocopherol, which were approximately 50% lower than in buoyant LDL (mol of antioxidant/mol of LDL) and together accounted for 80% of the variation in PnA oxidation lag times. These results suggest that PnA is a useful probe of LDL oxidative susceptibility and may be superior to conjugated dienes for monitoring the initial stages of LDL lipid peroxidation. Differences in oxidative susceptibility among LDL density subfractions are detected by the PnA assay and are due in large part to differences in their antioxidant content.     

耐烧蚀硅基纤维布增强酚醛树脂复合材料的高温氧化性能与力学性能

针对目前广泛应用的耐烧蚀硅基纤维布增强的复合材料存在的问题,比较了三种不同的硅基纤维布增强酚醛树脂复合材料的高温氧化后的失重率、力学性能和宏观/微观形貌的变化.发现高温氧化后,混编复合材料失重率的变化明显大于单编复合材料失重率的变化;高温氧化后材料的弹性模量随温度升高而减小.在三种硅基纤维布增强的复合耐蚀材料中,单编硅基纤维布增强的复合材料具有更好的抗高温氧化性能.      

减少板坯氧化烧损的措施

氧化烧损是金属热加工中影响经济技术指标的重要因素。轧钢加热炉在加热过程中钢的氧化烧损会造成一定的经济损失,同时氧化铁皮还会降低成品表面质量,延长钢在炉加热时间,增加停炉清渣次数等。通过分析、讨论影响板坯氧化烧损的因素,提出了降低板坯出炉目标温度、减少板坯在炉时间、合理控制炉内气氛等优化措施,板坯氧化烧损得到有效控制,创造了良好的经济效益和社会效益。     

High-Temperature Erosion-Corrosion Performance of High-Velocity Oxy-Fuel Sprayed Ni-20 Cr Coating in Actual Boiler Environment

The high-velocity oxy-fuel (HVOF) spray technique was used to deposit Ni-20Cr coating on a commonly used boiler steel ASTM A213 347H. The specimens with and without coating were exposed to the super heater zone of a thermal power plant boiler at a temperature of 973 K (700 °C) under cyclic conditions to ascertain their erosion-corrosion (E-C) behavior. High-temperature oxidation behavior of the specimens was also evaluated under cyclic thermal loading conditions at an elevated temperature of 1173 K (900 °C). Mass change data and thickness loss were measured to formulate the kinetics of E-C/oxidation for the specimens. The exposed specimens were characterized by X-ray diffraction (XRD) and field emission–scanning electron microscopy/energy dispersive spectroscopy (FE-SEM/EDS). The uncoated steel suffered higher E-C in comparison with its coated counterpart in terms of mass loss as well as thickness loss. It was observed that overall mass loss was reduced by 31 pct and thickness loss by 44 pct after the application of the coating. The possible formation of Cr₂O₃ phase in the coated substrate may be suggested to contribute to better E-C behavior. During air oxidation exposures, the coating was found to be intact with only marginal spallation of its oxide scales, which is an indicator of good adhesion between the coating and substrate steel. The air oxidation mass change data indicated that the coating enhanced the oxidation resistance of the steel by 85 pct.