共查询到20条相似文献,搜索用时 171 毫秒
1.
2.
3.
由于唐山钢铁公司一炼钢厂原用滑动水口系统存在一定缺陷,导致滑动机构使用的可靠性不强,且浇钢用滑板砖仅使用一次。这不但增加了工人的劳动强度及周转钢包数量,而且不利于钢包温度的提高,同时也造成浇钢系统耐火材料消耗较高。鉴于此,通过采取改进钢包滑动机构,调整滑板孔径和提高滑板质量等措施,解决了滑板面使用一次后即出现拉钢的现象以及时常出现的滑板刺钢事故,实现了钢包滑板连用。1滑动水口系统存在的问题1.1滑板孔径一炼钢供小方坯用钢包滑板直径50mm,因直径较大,在浇钢过程中需多次开关滑板。使用后的滑板侵蚀较严重,滑板面间… 相似文献
4.
新型铜-碳复合受电弓滑板的制备 总被引:3,自引:0,他引:3
通过分析当前电力机车受电弓滑板存在的各种问题,用粉末冶金法研制出了一种新型的受电弓滑板. 该滑板由铜、碳纤维和石墨等构成. 首先分析了成形压力、烧结温度对滑板性能的影响,然后对其导电性、摩擦、磨损性能及冲击韧性进行检测并与当前正在使用的受电弓滑板进行了对比. 结果表明,该新型滑板的最佳制备工艺条件为铜含量78%,碳纤维含量2%,石墨含量15%,添加剂含量5%,成形压力为200 MPa,烧结温度为880℃. 该滑板不仅电阻率很低,而且其摩擦、磨损及冲击韧性等性能也较当前正在使用的受电弓滑板优越. 与当前正在使用的碳滑板相比,其摩擦系数降低54.5%,磨损量减少41%,冲击韧性提高9.6倍,导电性增强87倍. 相似文献
5.
金属Al-Si结合Al2O3-C滑板的性能和使用 总被引:3,自引:3,他引:0
自主研制开发了节能型低碳金属Al-Si结合Al2O3-C滑板,其工艺特点是低温烧成,产品特性是低碳,与常用的Al2O3-C和Al2O3-ZrO2-C滑板相比,具有较高的热态强度,较好的抗热震性和抗氧化性。经大中型钢包的批量使用表明,其连续使用次数是高温烧成Al2O3-C滑板的两倍,与Al2O3-ZrO2-C滑板相当,用后滑板扩孔均匀,拉毛较少,裂纹微细。经残砖分析,认为金属Al-Si结合Al2O3-C滑板使用时的损毁过程可能是:表面工作层的非氧化物首先被氧化,导致结构疏松,强度降低,在铸孔处由高温钢水冲刷引起铸孔扩大,在滑动面处因机械摩擦造成滑动面拉毛。 相似文献
6.
7.
8.
9.
塑料树脂在合成和后处理过程及塑料制品在加工和使用过程种,由于热、氧等因素的作用,塑料高分子会有不同程度的降解,降解直接对树脂及制品的物理性能、力学性能、外观色泽、使用功能等产生负面作用。
使用抗氧剂是有效延缓树脂及制品降解或热氧老化的方法之一。抗氧剂的应用品种和添加量主要由塑料树脂的分子结构、聚合工艺、加工条件和制品用途决定。 相似文献
使用抗氧剂是有效延缓树脂及制品降解或热氧老化的方法之一。抗氧剂的应用品种和添加量主要由塑料树脂的分子结构、聚合工艺、加工条件和制品用途决定。 相似文献
10.
11.
金属-氮化物结合刚玉质滑板的结构与性能 总被引:7,自引:0,他引:7
由80%~90%板状刚玉及20%~10%金属铝组成的坯料经氮化处理(温度1100℃)后,再进行表面氧化处理(温度800℃),可制得显气孔率为2%的Al-AlN-Al2O3滑板材料,其1400℃高温抗折强度高达48.7 MPa. 该滑板材料浇钢的使用寿命是Al2O3-C滑板的2倍. 显微结构分析表明,部分金属铝氮化形成AlN的体积膨胀效应及其对刚玉晶粒的结合作用,提高了材料的结构致密度和强度,赋予材料优良的抗钢液侵蚀性能. 部分金属铝的高温塑性状态、金属铝及氮化铝的高导热性、刚玉与氮化铝的复相热失配等,是材料具有高抗热震性能的主要原因. 相似文献
12.
研究了不同添加物(电熔刚玉、镁铝尖晶石、碳化硅和阿隆)对镁碳材料物理性能和抗热震性的影响,炭素种类对镁碳材料物理性能和抗氧化性的影响以及抗氧化剂种类和加入方式对镁碳材料常温抗折强度和抗氧化性的影响,根据确定的最佳添加物研制连铸钢包用滑板材料。结果表明:加入镁铝尖晶石有利于提高材料的抗热震性;与炭黑相比,添加597微细石墨可显著提高材料的常温抗折强度、致密度以及抗氧化性;以碳化硼和硅粉作为复合添加剂,有利于提高材料中、高温处理后的常温抗折强度,同时也提高了材料的抗氧化性;研制的镁-尖晶石-碳滑板材料在实际使用中的抗拉毛性优于重烧铝锆碳滑板,达到了钢厂的使用要求。 相似文献
13.
14.
15.
采用解析法研究了第3类边界条件下双面陶瓷涂层三明治板的瞬态温度场及瞬态热应力场.对不同Biot模数的热冲击过程中,Al2O3涂层/硬质合金(WC-8%Co,质量分数)基体/Al2O3涂层三明治板的瞬态热应力进行了数值计算.分析了涂层/基体厚度比、涂层与基体热-物理性能匹配对陶瓷涂层三明治板表面热应力峰值的影响.结果表明:陶瓷涂层三明治板的基体的热导率、线膨胀系数和弹性模量应高于涂层,这样可以降低其表面热应力,获得高抗热震性陶瓷涂层三明治板.此外,涂层厚度应尽可能小,以利于改善涂层的抗热震性. 相似文献
16.
17.
18.
ZHONG Xiangchong 《中国耐火材料》2008,17(2):1-5
Some of the progress made in our laboratories in collaboration with industry in research and development work on high performance oxide-nonoxide composites for metallurgical applications has been reviewed. (1) SiAlON bonded corundum composites for blast furnace usage have been produced by reduction-nitridation sintering at high temperature, using bauxite instead of alumina in the matrix. (2) Low carbon Al2O3-SiAlON slide plate materials successfully used in high quality steel continuous casting have been developed in which most or all of the graphite in Al2O3-C brick is replaced by bauxite-based β-SiAlON. (3) Al/Si metal bonded Al2O3-C material characterized by low carbon content, low firing temperature and in-situ formation of carbides and nitrides at high temperature during service are found to possess very high hot strength and very good thermal shock resistance and have also been successfully used as slide plates in ladles and tundishes for high quality steel casting. 相似文献
19.
《Journal of Adhesion Science and Technology》2013,27(7):995-1016
Adhesive joints consist of adherends and an adhesive layer having different thermal and mechanical properties. When they are exposed to uniform thermal loads the mechanical-thermal mismatches of the adherends and adhesive layer result in uniform but different thermal strain distributions in the adhesive and adherends. The thermal stresses arise near and along the adherend-adhesive interfaces. The present thermal stress analyses of adhesively bonded joints assume a uniform temperature distribution or a constant temperature imposed along the outer boundaries of adhesive lap joints. This paper outlines the thermal analysis and geometrically non-linear stress analysis of adhesive joints subjected to different plate edge conditions and varying thermal boundary conditions causing large displacements and rotations. In addition, the geometrically non-linear thermal stress analysis of an adhesively bonded T-joint with single support plus angled reinforcement was carried out using the incremental finite element method, which was subjected to variable thermal boundary conditions, i.e. air streams with different temperatures and velocities parallel and perpendicular to its outer surfaces. The steady state heat transfer analysis showed that the temperature distribution through the joint members was non-uniform and high heat fluxes occurred inside the adhesive fillets at the adhesive free ends. Based on the geometrically non-linear stress analysis of the T-joint bonded to both rigid and flexible bases for different plate edge conditions, stress concentrations were observed at the free ends of adhesive-adherend interfaces and inside the adhesive fillets around the adhesive free ends, and the horizontal and vertical plates also experienced considerable stress distributions along outer surfaces. In addition, the effect of support length on the peak thermal adhesive stresses was found to be dependent on the plate edge conditions, when a support length allowing moderate adhesive stresses was present. 相似文献
20.
C. G. Aneziris U. Klippel W. Schärfl V. Stein Yawei Li 《International Journal of Applied Ceramic Technology》2007,4(6):481-489
One of the biggest challenges of refractory materials during metallurgical applications is the thermal shock performance. In terms of this work, different ways of improving the thermal shock resistance in carbon-bonded as well as in oxide-based materials by adding reactive titania powders are explored with the aid of thermal shock tests and followed by microstructure evaluation. The laboratory results obtained lead to microstructures with superior thermal shock properties and open the horizon of development of functional components such as slide gates or nozzles for clean steel technology. 相似文献