共查询到20条相似文献,搜索用时 234 毫秒
1.
2.
3.
氯乙烯-丙烯腈共聚物的开发及应用 总被引:3,自引:3,他引:3
叙述了氯乙烯-丙烯腈共聚物的难燃性、耐化学药剂性及热成型性等主要性能。指出,该共聚物可制得较优良的阻燃材料,并讨论了该共聚物的聚合方法。 相似文献
4.
5.
6.
105℃阻燃绝缘级PVC电缆料的研制吸取了70℃阻燃绝缘级电缆料的经验,合理选择增塑剂和阻燃剂,制得物理机械性能和阻燃性能满足105℃阻燃绝缘级标准的电缆料。试验结果表明,该阻燃电缆料的二次加工性能好,加工温度范围宽,易于操作,制得的电线符合生产厂家的技术要求。 相似文献
7.
8.
注塑成型条件对聚甲醛制品冲击性能的影响 总被引:1,自引:0,他引:1
用精密注塑机加工成型聚甲醛制品,考察了注塑成型条件如注射压力、注射时间、冷却时间、模具温度、后处理条件等对制品冲击性能的影响,找到了最佳工艺条件,制得了冲击性能优良的聚甲醛制品。由扫描电镜观察、结晶度测定和X射线衍射分析表明,聚甲醛制品的冲击韧性与其局部缺陷、裂纹、结晶度、晶粒大小等有关,只有改善制品的均匀性,减少局部缺陷的产生控制结晶度和晶粒大小在适当范围,才能制得冲击性能优良的制品。 相似文献
9.
传动器通过注塑成型工艺制得,其成型质量直接影响传动器的性能。在注塑成型工艺过程中,模具温度、熔体温度、保压压力以及冷却时间等工艺参数对制件的影响较显著,不合理的工艺参数导致制件出现较大的翘曲变形。通过建立响应面模型,以模具温度、熔体温度、保压压力以及冷却时间为响应参数,以制件的翘曲变形量为响应目标,优化一组最佳的成型工艺参数组合。结果表明:四个变量的影响程度分别为:模具温度>保压压力>冷却时间>熔体温度。当模具温度80℃、熔体温度180℃、保压压力90 MPa、冷却时间20 s,制件的翘曲变形量最小为1.955 mm,较未优化的翘曲变形量降低0.427 7 mm,有效地改善了制件的成型质量。 相似文献
10.
聚三氟氯乙烯加工工艺的探讨 总被引:1,自引:0,他引:1
<正> 氟塑料是各种含氟塑料的总称,由含氟单体如四氟乙烯、六氟丙烯、三氟氯乙烯、偏氟乙烯、氟乙烯以及乙烯等通过均聚或共聚反应制得。含氟塑料与其它热塑性塑料比较具有优越的耐高低温、耐腐蚀、摩擦系数低、绝缘性能好等特性,已成为尖端科学技术,军工生产以及其它工业部门所不可缺少的材料之 相似文献
11.
Anitha Nithyanandam Thenmuhil Deivarajan 《International Journal of Applied Ceramic Technology》2021,18(5):1825-1831
Cenosphere-based composite was developed with addition of clay and other additives, by dry processing route. The performance of cenosphere as high-temperature insulating material was studied. Cenosphere stands unique among the constituents found in fly ash due to its hollow spherical structure. Cenosphere is utilized in numerous modern applications due to its unique properties such as lightness, high compressive strength, enhanced flow characteristics, less water absorption, chemical inertness, and good thermal resistance. Keeping cenosphere as major component, three different mix recipes for insulating brick were made. The recipes were blended and shaped by pressing, followed by drying and sintering at 1000°C. The prepared samples were analyzed for their physical, mechanical, and thermal properties. The surface and pore distribution are analyzed by scanning electron microscope. Results from the analysis shows that cenosphere can be used as high temperature insulating material. 相似文献
12.
13.
Hailu Wang Yuanbing Li Bo Yin Shujing Li Xiaohong He Ruofei Xiang Zhe Qiao 《International Journal of Applied Ceramic Technology》2023,20(5):3237-3245
In order to realize efficient and comprehensive utilization of kyanite tailings (KT) mullite insulating firebrick (M-IFB) with high strength and low thermal conductivity with spherical-low connectivity porous were success fully prepared by using KT and alumina as the main raw material. Control of the porosity and properties of mullite insulating firebrick can be easily and accurately achieved by adjusting the heat treatment temperature and the amount of forming agent. The compressive strengths, bulk density, thermal conductivities, liner change, and porosities ranged from 25.86–53.26 MPa, .58–1.61 g/cm3, .236–.599 W/(m·K), −1.01 to −.426 % and 66.89 to 78.63 %, respectively. The creep rate of M-IFB was compared with that of current insulating bricks after them used in the baking kiln of lithium ion battery cathode materials in the laboratory to simulate the environment. The results show that the M-IFB corrosion resistance was obviously superior to the current insulation bricks. The high porosity high strength mullite insulating firebrick prepared by this method is expected to be used in thermal insulation system of kiln to realize the comprehensive utilization of solid waste. 相似文献
14.
This work describes a panel made from waste polyethylene, henequen fibers, and mineral fillers. The physical and mechanical properties of the product were determined and compared with the properties of commercial panels. The new material has good mechanical properties and high environmental resistance. Its thermal insulating capacity is about 10 times better than that of asbestos–cement panels. The adhesion grade between fibers and polymer was investigated. 相似文献
15.
熔融铜渣回收铜及铜铁合金工艺研究 总被引:3,自引:0,他引:3
本文根据某炼铜熔融炉渣的矿物特性和选矿工艺特点,提出了一种"两步法"新工艺分别回收铜和铜铁合金,即低温阶段回收铜,高温阶段回收铜铁合金。该工艺对铜和铜铁合金提取比较充分,回收率均在90%以上。回收铜的品位可达99%,可直接送去火法精炼;产出的铜铁合金有害杂质少,可作为耐候钢的理想原料,其价值比纯铁高。此工艺用粉状或粒状非焦煤代替焦炭作还原剂,不用烧结,可以充分利用铜厂现有的设备,节省投资成本。该工艺简单易行,操作方便,有效实现了铜渣的资源化利用,具有良好的经济、社会和环境效益,是一种应用前景广阔的铜渣再利用工艺。 相似文献
16.
17.
Vermiculite, a mineral of natural occurrence of the group of hydromicas, when heated to above 300°C, expands to become a highly efficient heat-insulating material. The expanded vermiculite, owing to its unique properties – low bulk density, low heat conductivity, relatively high melting point, chemical inertness, endurance, and environmental safety – can be used as a filler for heat-insulating materials. Heat insulators based on expanded vermiculite can be used in thermal power units with the hot-wall temperature not exceeding 1150°C as replacement for lightweight chamotte components and fibrous heat insulators. 相似文献
18.
Photooxidation of anhydride-cured epoxies: FTIR study of the modifications of the chemical structure
Anhydride-cured epoxies are used in electrical engineering to manufacture insulators. The purpose of this study is to determine the modifications undergone by these resins when exposed to solar-type radiation (radiation with a wavelength of more than 300 nm). Two epoxy–anhydride systems have been studied. Using transmission Fourier transform infrared (FTIR) and attenuated total reflection (ATR), we have determined the structural modifications and the groups formed during photooxidation. The degradation is very heterogeneous, more significant on the surface than in the bulk of the material, and a considerable decrease in almost all the initial functional groups is observed. The flexibilized system, richer in ester groups but containing fewer phenyl groups, degrades more rapidly during the first hours of exposure than the nonflexibilized system. Two explanations accounting for this faster degradation in the first hours of exposure are drawn from ultraviolet absorbance analysis and degradation mechanisms considerations. After 40 h of irradiation, the disappearance rate of the aromatic groups depends only on their initial concentration, whereas the formation kinetics for the hydroxyl groups is limited by the diffusion of oxygen in the material. Chemical treatments using SF4, NH3, and NaCl have revealed the formation of hydrophilic products, acids, and alcohols. Their presence and particularly high concentration at the surface could very well be responsible for the degradation of the insulating properties of the electrical insulators. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 1221–1237, 1998 相似文献
19.
20.
利用长江沿岸低品位石英砂开发研制保温隔热砖,研究球磨参数对低品位石英砂粒径的影响,为制备高性能的保温隔热砖奠定原料基础。研究结果表明:随着球磨时间的延长,石英砂粒径减小;随着球磨转速的增加,石英砂粒径逐渐减小;随着球磨机装料量的增加,石英砂的粒径增加;随着球比的增加,石英砂粒径逐渐增加。综合考虑整个工艺过程性价比,确定最佳球磨参数为:球磨时间为60min,球磨转速为300r/min,球磨机装料量为200g/L,大小球质量比值为0.75。 相似文献