镁钙质中间包涂料净化钢水的试验研究

本文根据中包工作层使用镁钙质涂料的试验结果,通过对涂料残块的成分变化、岩相检测和钢水夹杂物量的变化分析,阐述了该涂料对进一步净化钢水的作用。     

“高反射隔热板”的开发

对付地球温暖化的措施之一是使用隔热涂料，对此，本研究开发了高反射隔热板。历来的隔热涂料均以现场涂装为主，而本开发考虑到现场涂装造成的涂膜质地波动及长年使用污染粘附造成的性能降低等，通过在工厂烧粘涂装，确保膜质的稳定性，并采用光催化剂抑制防污性能，防止日照反射率的降低。通过户外曝露和耐候性试验，观察了“高反射隔热板”的日照反射率的变化和涂膜老化状况，确认利用光催化剂能够维持日照反射率的初期性能，涂膜性能也和通用涂料基本相等。     

高温涂料在加热炉上应用的实践

通过辐射传热公式分析了高温涂料节能的理论基础，分析了影响该涂料使用的主要因素，通过热工检测给出确定该涂料使用效果的有效方法，并指了应用中需要注意的一些问题。     

高温红外涂料对格子砖蓄热性能影响的实验研究

通过试验分析得出涂料对格子砖蓄热能力的影响，并分析温度对红外涂料效果的影响，得出涂料使用的理想温度范围。     

连铸中间包镁质涂料及其抗渣性的研究

对中间包工作衬用镁质涂料的配比及其抗渣性进行了研究。结果表明：适量的结合剂、添加剂及合理的颗粒级配，可制成具有最佳性能的镁质涂料；通过岩相分析可知，涂料中存在一致密层，阻止渣进一步渗透，具有良好的抗渣性；镁质涂料做中间包工作衬具有良好的抗渣性能和易解体性。     

减少中间包渣在涂料中渗透的途径

中间包渣在涂料中的渗透是景作料用后解体性能的关键因素。通过减小涂料气孔直径，增加中间包渣粘度及提高涂料基质的耐高温性能可以改善涂料的抗渗透性能。     

90吨转炉渣罐喷涂料的研制与应用研究

本主要介绍了一种廉价渣罐喷涂料的研制生产过程。在研制过程中，通过大量的实验室实验和工艺试验，最终研制出符合新翻渣工艺的最佳喷涂料。通过现场使用，自动翻罐率高达96％以上，创年效益120万元，达到了立项攻关的目的。     

Km高温抗蚀耐磨涂料在省煤器中的应用

锅炉省煤器磨损一直是困绕锅炉稳定运行的主要因素之一。本介绍了Km高温抗蚀耐磨涂料的性能、特点，以及在实际生产中的使用情况，通过实践充分肯定了Km高温抗蚀耐磨涂料的可行性、可靠性和经济性。     

谈保温涂料在铝电解槽上的应用

通过保温涂料在75kA电解槽上的应用后，使我们了解到使用保温涂料可优化技术指标，更好地组织生产，最终反映到吨铝电耗降低，从而达到节能的效果，降低生产成本。     

脱硫铁水罐渣线喷涂料的研究

通过脱硫铁水罐渣线结渣状况的现场调研，弄清了渣线喷涂料的性能要求，完成了原材料的选择分析，在实验室实验研究的基础上，进行了喷涂料的工业性试验与扩大性工业试验，取得了附着率大于90％、喷涂面平整、喷涂量少与降低结渣速度的优良效果。     

连续热浸镀铝硅钢板镀层微观结构研究

 热浸镀铝硅钢板具有优良的耐热性、耐腐蚀性、耐高温氧化性,目的是研究铝硅镀层钢板的镀层微观结构和性能。利用热镀锌模拟器在实验室条件下制备了热浸镀铝硅镀层钢板,通过扫描电镜、电子探针对镀层的微观组织结构、镀层中元素的平面分布进行了观察,利用X-射线研究了铝硅镀层的物相组成,利用盐雾试验研究了镀层钢板的耐腐蚀性能。结果表明,铝硅镀层由占主要富铝的树枝晶、树枝晶间的铝硅二元合金、铁铝界面层及分布于基体中的块状相组成,镀层组织均匀,结合较好,耐蚀性优良。     

CeO2对不锈钢基SiO2-BaO-Al2O3-Cr2O3陶瓷涂层性能的影响

采用高温熔烧法于1Cr18Ni9Ti不锈钢基材表面制备掺CeO2的SiO2-BaO-Al2O3-Cr2O3陶瓷涂层,研究了不同含量CeO2对涂层的抗氧化性、抗热震性和硬度的影响。研究结果表明,含CeO2的不锈钢基SiO2-BaO-Al2O3-Cr2O3陶瓷涂层能有效阻止不锈钢基体的氧化增重,提高涂层的抗热震性能及硬度。本实验条件下,CeO2含量2.8%时,涂层具有最好的抗氧化性能和抗热震性能。     

Flame Pyrolysis Spraying of Alumina-Yttria Ceramic Coating

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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.     

热处理工艺对铝硅镀层热成形钢组织性能的影响

为深入理解不同热处理工艺参数对铝硅镀层热成形钢组织性能的影响规律,主要研究了加热温度和保温时间对铝硅镀层热成形钢的硬度、微观组织、镀层厚度和镀层成分的影响。结果表明,当加热温度不大于 900 ℃ 时,铝硅镀层热成形钢的硬度随着保温时间的增加而增加;当加热温度大于 900 ℃ 时,铝硅镀层热成形钢的硬度随着保温时间的增加而下降。当加热温度为850~930 ℃,保温时间为 4、8 min 时铝硅镀层热成形钢的微观组织在模具淬火冷却过程中均转化成为马氏体。在相同加热温度下,铝硅镀层热成形钢合金层的厚度随着保温时间的增加而增大,当加热温度升高至 930 ℃ 时,镀层因氧化而挥发严重,导致镀层变薄,所以铝硅镀层热成形钢的加热温度应控制在 930 ℃ 以下。保温温度升高、保温时间增加导致元素扩散显著,聚集的硅元素含量和面积由于其不断向四周扩散而降低。同时铁元素大量扩散到镀层中,镀层中铁元素含量增加显著。高温下,镀层发生明显的氧化反应,氧化反应促进了微孔洞的形核和长大。     

M152钢基体超音速火焰喷涂WC-17Co涂层性能研究

采用超音速火焰喷涂技术在M152钢上制备了WC-17Co涂层。对WC-17Co涂层的耐磨性能和耐蚀性能进行了研究。结果表明超音速火焰喷涂WC-17Co涂层显著提高了M152钢基体的抗盐雾腐蚀性能,同时WC-17Co涂层具有优异的抗氧化性能和耐磨性能,可用于M152钢零件中温区域的耐磨、耐蚀防护。     

Effect of Rare Earth on Void Band of Diffusion Layer and Properties of Aluminized Steel

 The effects of the addition of rare earth (RE) elements on the void band in the diffusion layer, and the resistances to both oxidation and spalling of aluminized steel were investigated through high temperature oxidation and spalling tests. The results showed that RE had significant effects on the void band in the diffusion layer and the properties of aluminized steel. After diffusion treatment, a considerable number of the voids between the middle layer and transitional layer of pure aluminized coating, aggregated into wavy line shaped void bands parallel to the outer surface. For the RE added aluminized coating, only a few voids aggregated into intermittent block shapes. During high temperature oxidation at 800 ℃ for 200 h, the wavy void band of pure aluminized coating aggregated further into a linear crack parallel to the outer surface, and the internal oxidation occurred within them; the open cracks perpendicular to the surface penetrated through the diffusion layer. For the RE added aluminized coating, only a few voids aggregated into intermittent meniscus shapes. During cyclic spalling tests, the peeling, spallation, and pulverulent cracking occurred along the void band in the diffusion layer of pure aluminized coating, but only a little spallation occurred in the diffusion layer of the RE added aluminized coating, in which cracks perpendicular to the surface were much smaller than those of pure aluminized coating and did not penetrate through the diffusion layer. It is evident that RE addition can restrain the formation and aggregation of voids and subsequently improve the resistances to oxidation and spalling. The mechanism of the RE effect on the void band in the diffusion layer is also discussed.     

链箅机箅板用新型Fe-Cr基耐热钢的抗氧化性能研究

根据链箅机箅板的工况条件,设计了5种成分不同的箅板用Fe—Cr基耐热钢,研究了它们在900℃的工况温度下抗氧化性能的变化规律,分析了氧化膜的构成及其形貌,测定了氧化膜的粘附力。     

State‐of‐the‐Knowledge on Coating Systems for Hot Stamped Parts

In the present contribution, recent developments of coatings for hot stamped steels are reviewed. The use of bare steel in the initial hot stamping technology is discussed, including the application of lubricant oils which are used as oxidation inhibitors on bare steel surfaces. The aluminized coatings are introduced, focusing on the microstructure evolution of aluminized coatings during the hot stamping process. An analysis of the cracking of the coating, caused by the formation of brittle Fe–Al intermetallic phases and their high temperature deformation, is presented. The development of a ductile aluminide coating formed during the diffusion treatment of an aluminized coating is discussed. This aluminide coating can endure both high temperature oxidation and severe plastic deformation. The recently developed galvanized and galvannealed coatings are also reviewed and the influence of the gas atmosphere during the heating cycle on the coating stability is emphasized. The solutions which have been proposed to avoid liquid Zn‐induced embrittlement are analyzed. The use of Zn–Ni alloy coating, which is characterized by a higher melting temperature, is reviewed. The behavior of sol–gel hybrid coatings on hot stamped steels is discussed. The possible use of the recently developed Al–Zn alloy coatings, dual layer Zn–Al and Zn–Al–Mg coatings is also introduced. The application of Zn–Al–Mg post‐process galvanizing is also discussed. In each case, all available information related to the weldability, paintability, and corrosion resistance of the coating systems is also reported. Finally, the advantages and technical challenges associated with each type of coating are reviewed.     

Microstructure and high-temperature properties of Fe-Ti-Cr-Mo-B-C-Y_2O_3 laser cladding coating

Fe-based composite coatings were fabricated on 5 CrNiMo die steel by laser beam melting a precursor mixture of ferrotitanium,ferrochromium,ferromolybdenum,B4 C and Y_2 O_3 powders.Micro structure and properties of the coatings were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive spectrometer(EDS),resistance furnace and high-temperature tribometer.The results show that(Ti,Mo)C particles with flower-like and(Ti,Mo)B_2 with block-like shapes are in situ formed during laser cladding.Volume faction of multiple ceramic particles increases with the increasing of Y_2 O_3.The cumulative oxidation mass of the coating with 2 wt% Y_2 O_3 is decreased by one-third than that of the coating without Y_2 O_3.The oxidation layer of the coating with Y_2 O_3 is getting smooth.Meanwhile,high temperature wear volume loss of the coating with 2 wt% Y_2 O_3 is about 40% that of the coating without Y_2 O_3.The coating with 2 wt% Y_2 O_3 shows a smoother wear scar and few flat grooves are observed after high temperature wear test.