|
|
石英砂热形态和表面微观结构
Thermal behavior and surface microstructure of quartzite particles
查看参考文献9篇
|
文摘
|
使用由德国生产的LEIAZ-ⅡA型高温热显微镜对异密度循环流化床床料——石英砂在加热过程中所表现出的熔融特性和热膨胀特性进行了研究。高纯度石英砂在升温过程（室温～1600℃）中存在3个相对独立的特征温度区间：缓慢膨胀区（室温～870℃），在此区间试样尺寸变化比较均匀，线膨胀速率k比较小；膨胀停滞区（1000-1350℃）内，试样的体积和形状几乎不随温度的升高而改变，k在此区间近于零；快速膨胀区（1400-1550℃）内，k在此区间突然增大，形成一个陡峭的波峰。升温过程中高纯度石英砂试样的膨胀特性与其多晶型转变温度有对应关系。通过不同纯度两个试样的对比实验发现，纯度直接影响石英砂的熔融特性，纯度高，则相应的特征温度值高。利用HITACHIS2150型扫描电子显微镜（SEM）对加热到不同终端温度并冷却到室温的高纯度石英砂颗粒亚稳相的微米级表面结构进行观察，当终端温度进入快速膨胀区后，试样由于剧烈的膨胀在表面和内部产生大量微观裂纹，大量微观裂纹的存在导致试样的力学性能急剧下降，表现为弹性能力的消失。 |
|
其他语种文摘
|
The melting characteristics and thermal expanson behavior of quartzite particles during heated-up were studied by using a thermal microscope (LEIAZ-Ⅱ)made in Germany.The results showed that the linear expansion rate of high purity quartzite had three different regions at different temperatures, namely, slow-expansion region(room temperature—870℃), halted expansion region (1000—1350℃)in which the linear expansion rate tended to be zero, and fast-expansion region (1400—1550℃) with a sharp wave crest, respectively.These regions were corresponding to the isomer conversion of SiO2.The comparison between two samples with different purities showed that the purity of quartzite particle had a remarkably influence on its melting characteristics.A particle with higher purity tended to have a higher characteristic temperature of melting characteristics.Furthermore, the surface microstructure of the high purity quartzite particles heated at different terminal temperatures was also observed by using a scanning electron microscope (HITACHI) S2150.Numerous micro-cracks (about ten microns) would be formed on the surface of the sample when the terminal temperature reached the fast expansion region, and the structure inner the sample was very loosen with numerous of minor-cracks(about one micron in width).These minor-cracks lead to the lose of elasticity and worsened mechanical properties of samples. |
|
来源
|
化工学报
,2007,58(3):765-770 【核心库】
|
|
关键词
|
石英砂
;
熔融特性
;
热膨胀
;
异密度循环流化床
|
|
地址
|
1.
上海交通大学机械与动力工程学院, 上海, 200240
2.
哈尔滨工业大学能源科学与工程学院, 黑龙江, 哈尔滨, 150001
|
|
语种
|
中文 |
|
文献类型
|
研究性论文 |
|
ISSN
|
0438-1157 |
|
学科
|
一般工业技术 |
|
基金
|
国家自然科学基金项目
|
|
文献收藏号
|
CSCD:2868382
|
参考文献 共
9
共1页
|
|
1.
姜秀民. 水煤浆流化悬浮高效洁净燃烧技术研究与应用.
化学工程,2006,34(1):62-65
|
被引
7
次
|
|
|
|
|
2.
Li Xiaodong. Study on mixing performance of municipal solid waste(MSW)in differential density fluidized beds(FBs).
Chemical Engineering Journal,2001,84(2):161-166
|
被引
6
次
|
|
|
|
|
3.
别如山. Influence of additives on bed sintering in fluidezed bedincinerator treating waste salty liquid.
化工学报,2002,53(12):1235-1259
|
被引
2
次
|
|
|
|
|
4.
李晓东. Agglomeration characteristics in fluidized bed incineration of organic-condensed wastewater.
化工学报,2005,56(11):1266-1271
|
被引
2
次
|
|
|
|
|
5.
Shanker J. Theory of thermal expansivity and bulk modulus for MgO and other minerals at high temperatures.
Physica B,1997,233(1):78-83
|
被引
3
次
|
|
|
|
|
6.
Srivastava S K. Model for evaluating and predicting thermal expansivity at high temperatures for geophysical minerals.
Physica B,2005,355(4):32-36
|
被引
1
次
|
|
|
|
|
7.
廖立兵. 矿物热膨胀系数计算的修正Ruffa法及其应用.
矿物学报,2003,23(4):349-354
|
被引
3
次
|
|
|
|
|
8.
崔守鑫. 氯化钠晶体在高温高压下热物理参数的分子动力学计算.
物理学报,2005,54(6):2826-2831
|
被引
9
次
|
|
|
|
|
9.
胡赓祥.
材料科学基础,2000:203
|
被引
2
次
|
|
|
|
|
|
了解气象卫星更多信息，请访问