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11.
介绍在团粒法工艺的基础上,将尿素熔融成尿液进行喷浆造粒生产复合肥的过程中,存在的问题,原因及解决的对策。 相似文献
12.
13.
臭氧在食品加工用水处理工程上的应用 总被引:2,自引:0,他引:2
本文叙述了臭氧的一些特性 ,并以烟台某食品加工公司食品加工用水处理工程为例 ,介绍了臭氧的产生及应用情况 ,提供了处理前后水中各项指标的对照 相似文献
14.
15.
几种火焰喷焊自熔性合金层的耐磨性能 总被引:7,自引:0,他引:7
研究了不同自熔性合金粉末火焰喷焊层的显微组织与抗磨粒磨损性能,并对其磨面形貌进行了SEM观察分析。结果表明,在Ni60自熔性合金中加入适量的镍包WC粉末可明显提高其喷焊层的抗磨粒磨损性能。当WC的加入量为35%(wt)左右时,该喷焊层与60Si2Mn调质钢相比,相对的耐磨性可提高6倍以上。 相似文献
16.
耐火纤维喷涂辅助技术 总被引:5,自引:2,他引:3
文章主要论述了耐火纤维喷涂炉衬的特点及性能,以及对辅助工艺的要求,并对耐纤喷涂炉衬和纤维喷涂针刺炉衬进行了试验对比,说明耐火纤维喷涂技术前景广阔。 相似文献
17.
针对选煤厂运煤火车人工喷洒防冻液不均匀的问题,设计了一种基于CC-Link的火车皮防冻液自动喷洒系统。该系统采用CC-Link现场总线技术将多套喷洒装置和防冻液加压泵站构建成工业现场级控制网络,实现了各装置之间的联动和实时监控。实际应用表明,该系统避免了防冻液的浪费,提高了工作效率。 相似文献
18.
19.
The deposition of copper by cold gas dynamic spraying has attracted much interest in recent years due to the capability to
deposit low-porosity oxide-free coatings. However, it is generally found that as-deposited copper has a signicantly greater
hardness, and potentially lower ductility, than bulk material. In this article, copper was deposited by cold spraying using
helium as the driving gas at both 298 and 523 K. Evidence is presented indicating that the material sprayed at the lower temperature
exhibits a lower dislocation density throughout the grain structure than the material sprayed at the higher temperature. The
low stacking fault energy of copper restricts recovery during annealing, and thus microstructural changes during annealing
only proceed once recrystallization begins. The material sprayed at low temperature (with the low dislocation density) exhibited
recrystallization at annealing temperatures as low as 373 K with a corresponding reduction in hardness. However, the copper
sprayed with helium at 523 K was resistant to annealing at temperatures up to 473 K where the dislocations in the structure
prevented recrystallization. However, at higher temperatures, recrystallization did proceed (with corresponding reductions
in hardness). The fracture behavior of the copper that was cold sprayed with helium at 523 K, both in the as-sprayed condition
and following annealing, was measured and explained in terms of the annealing mechanisms proposed.
The original version of this paper was published in the CD ROM Thermal Spray Connects: Explore Its Surfacing Potential, International
Thermal Spray Conference, sponsored by DVS, ASM International, and HW International Institute of Welding, Basel, Switzerland,
May 2–4, 2005, DVS-Verlag GmbH, Düsseldorf, Germany. 相似文献
20.
G. Antou F. Hlawka A. Cornet G. Montavon C. Coddet F. Machi 《Journal of Thermal Spray Technology》2004,13(3):381-389
Several studies have been undertaken recently to adapt yttria partially stabilized zirconia (YPSZ) thermal barrier coating
(TBC) characteristics during their manufacturing process. Thermal spraying implementing laser irradiation appears to be a
possibility for modifying the coating morphology. This study aims to present the results of in situ (i.e., simultaneous treatment)
and a posteriori (i.e., post-treatment) laser treatments implementing a high-power laser diode. In both cases, the coatings
underwent atmospheric plasma spraying (APS). Laser irradiation was achieved using a 3 kW, average-power laser diode exhibiting
an 848 nm wavelength. Experiments were performed to reach two goals. First, laser post-treatments aimed at building a map
of the laser-processing parameter effects on the coating microstructure to estimate the laser-processing parameters, which
seem to be suited to the change into in situ coating remelting. Second, in situ coating remelting aimed at quantifying the
involved phenomena. In that case, the coating was treated layer by layer as it was manufactured. The input energy effect was
studied by varying the scanning velocity (i.e., between 35 and 60 m/min), and consequently the irradiation time (i.e., between
1.8 and 3.1 ms, respectively). Experiments showed that coating thermal conductivity was lowered by more than 20% and that
coating resistance to isothermal shocks was increased very significantly. 相似文献