CN107244899A - 一种高致密陶瓷内衬钢管的制备方法 - Google Patents

一种高致密陶瓷内衬钢管的制备方法 Download PDF

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CN107244899A
CN107244899A CN201710361352.3A CN201710361352A CN107244899A CN 107244899 A CN107244899 A CN 107244899A CN 201710361352 A CN201710361352 A CN 201710361352A CN 107244899 A CN107244899 A CN 107244899A
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刘大猛
王婷
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Abstract

本发明涉及一种高致密陶瓷内衬钢管的制备方法，属于自蔓延陶瓷内衬钢管技术领域，该方法是将轴向研磨棒置于钢管内，固定于侧向，将铝热剂按一定比例混合填充于钢管内，使钢管在离心力的作用下高速旋转，点火使铝热剂发生SHS反应，反应产生大量的热，生成熔融状态的Al2O3和Fe，形成陶瓷层内衬。当产物处于熔融状态时，由于钢管仍继续高速旋转，钢管内的研磨棒不断将产物中的气泡压出，使生成的涂层材料致密性增强，同时使陶瓷表面平整，冷却后得到光滑致密的陶瓷内衬钢管。本发明制备的陶瓷内衬钢管，方法简单，原料成本低，制备出的钢管具有高精度，高致密度和高强度的特点，耐磨性和耐腐蚀性强。

Description

一种高致密陶瓷内衬钢管的制备方法
技术领域
本发明属于自蔓延陶瓷内衬钢管技术领域，特别是提供一种高致密陶瓷内衬钢管的制备方法。
背景技术
现代工业，如电力、化工、冶金等行业中，耐磨、防腐蚀型管道有着广泛的应用。自蔓延高温合成(SHS)技术是一种利用外部能量诱发局部化学反应，利用化学反应自身放热，使反应持续进行，迅速制备材料的新技术。该理论由前苏联科学家Merzhanov于1967年提出，并开展了离心力场对凝聚态物质燃烧过程影响的研究。随后美国和日本等国学者又详细研究了该工艺。小田原修在1981年通过SHS离心技术，制备出长5 500mm、直径330mm的陶瓷内衬钢管。
该陶瓷内衬钢管制备方法所涉及的技术原理是，将装填反应原料铝热剂的钢管夹在高速离心机上，离心机产生的离心力，使反应原料紧贴于钢管内壁，在钢管一端引燃反应原料，反应原料依化学反应方程式：Fe2O3+2Al＝Al2O3+2Fe，高温烧结，发生SHS反应。反应时放出大量的热使产物融化，由于产物熔体的密度不同，在离心力的作用下，密度大的Fe与基体结合，密度小的Al2O3沿钢管内壁均匀分布，形成陶瓷层。
但是实施上述制备方法时，由于钢管管壁有强烈的冷却作用，使反应产物处于熔融状态的时间很短，里面产生的大量气泡来不及排除，而得不到致密的氧化铝陶瓷层。
为了增加陶瓷层的致密性，殷声等人(中国专利90107244.3)在反应物中加入各种添加剂，如SiO2或碱金属氧化物或碱土金属氧化物。由于添加剂的存在，可以使陶瓷层的熔点降低，从而延长其在熔融状态停留时间，从而提高陶瓷层的致密度。但是这种方法制备的陶瓷层中仍会残留一定量的气孔，使得成品裂纹率提高，而且成本也高。
发明内容
本发明的目的在于，为克服已有技术不足之处，提出一种高致密陶瓷内衬钢管的制备方法，本方法提高钢管内壁陶瓷层的致密度，使得陶瓷内衬管具有良好的机械性能，耐腐蚀，耐热冲击，显微硬度有较大的提高。
为达到上述目的，本发明提出一种高致密陶瓷内衬钢管的制备方法，其特征在于，该方法包括以下步骤：
1)将研磨棒沿轴向安装于钢管内，其轴线与钢管轴线平行，研磨棒的两端固定于钢管的支撑物上，研磨棒的侧面与钢管内侧面留有一缝隙，该缝隙宽度与形成的陶瓷层厚度相适应(其安装位置可随陶瓷层的厚度要求变动)；
2)将铝热剂按一定比例混合填充于钢管内，使钢管在离心力的作用下高速旋转，点火使铝热剂发生SHS反应，反应产生大量的热，生成熔融状态的Al2O3和Fe的产物，形成陶瓷涂层内衬，同时钢管内的研磨棒不断将产物中的气泡压出，使生成的涂层材料致密性增强，并使陶瓷表面平整；
3)钢管冷却后取出研磨棒，得到光滑致密的陶瓷内衬钢管。
所述铝热剂为Fe2O3+Al，所述SHS反应为Fe2O3+2Al＝Al2O3+2Fe。
本发明中可采用2或3根研磨棒，其长度可等于或略大于制备的钢管长度，直径以不妨碍铝热剂的均匀喷涂过程为宜。
本发明的特点及有益效果：
本发明的制备方法由于熔体的密度不同，在离心力的作用下，密度大的Fe与钢管基体结合，密度小的Al2O3沿内壁均匀分布，形成陶瓷层内衬。当产物处于熔融状态时，由于钢管仍继续高速旋转，钢管内的研磨棒不断将产物中的气泡压出，使生成的涂层材料致密性增强，同时使陶瓷表面平整，则冷却后得到光滑致密的陶瓷内衬钢管。
凡是使用内置研磨手段来增加陶瓷内衬钢管内壁陶瓷层致密性的方法，都在本专利的保护范围之内，其中包括使用不同形状、尺寸和数量的研磨棒类零件。
本发明制备的陶瓷内衬钢管，方法简单，原料成本低，制备出的钢管具有高精度，高致密度和高强度的特点，耐磨性和耐腐蚀性强。
具体实施方式
本发明提出的一种高致密陶瓷内衬钢管的制备方法结合实施例进一步说明如下：
生产内衬厚为5mm的陶瓷复合钢管的实施例包括以下步骤：
1)将三根研磨棒2(所用材料为Al2O3，棒直径为50mm,长为1000mm)沿轴向置于钢管1(钢管直径Φ为430mm，长为1000mm,厚度为12mm)内，其轴线与钢管轴线平行，研磨棒的两端固定于钢管的支撑物上，研磨棒的侧面与钢管内侧面留有一缝隙，该缝隙宽度约为5mm；
2)将铝热剂的成分Fe2O3+Al按质量：铝粉(5936g)，氧化铁粉(20860g)，长石粉(392g)，石英粉(392g)，混合填充于钢管内，使钢管在离心力的作用下高速旋转，当离心机转速达到380转/分时，点火使铝热剂发生SHS反应Fe2O3+2Al＝Al2O3+2Fe，反应放出大量的热，生成熔融状态的Al2O3和Fe。由于熔体的密度不同，在离心力的作用下，密度大的Fe与钢管基体结合，密度小的Al2O3沿内壁均匀分布，形成厚度为5mm的陶瓷层内衬。当产物处于熔融状态时，由于钢管仍继续高速旋转，钢管内的研磨棒不断将产物中的气泡压出，使生成的涂层材料致密性增强，同时使陶瓷表面平整，
3)钢管冷却后取出研磨棒，得到光滑致密的陶瓷内衬钢管。
本发明中的可采用2或3根Al2O3研磨棒，其长度可等于或略大于制备的钢管长度，直径以不妨碍铝热剂的均匀涂覆过程为宜。
本发明制备的陶瓷内衬钢管，方法简单，原料成本低，制备出的钢管具有高致密度(可达到80％～95％)。高强度和高精度的特点，耐磨性和耐腐蚀性强。

Claims (3)

1.一种高致密陶瓷内衬钢管的制备方法，其特征在于，该方法包括以下步骤：
1)将研磨棒沿轴向安装于钢管内，其轴线与钢管轴线平行，研磨棒的两端固定于钢管的支撑物上，研磨棒的侧面与钢管内侧面留有一缝隙，该缝隙宽度与形成的陶瓷层厚度相适应；
2)将铝热剂按一定比例混合填充于钢管内，使钢管在离心力的作用下高速旋转，点火使铝热剂发生SHS反应，反应放出大量的热，生成熔融状态的Al2O3和Fe的产物，形成陶瓷涂层内衬，同时钢管内的研磨棒不断将产物中的气泡压出，使生成的涂层材料致密性增强，并使陶瓷表面平整；
3)钢管冷却后取出研磨棒，得到光滑致密的陶瓷内衬钢管。
2.如权利要求1所述制备方法，其特征在于，所述铝热剂为Fe2O3+Al，所述SHS反应为Fe2O3+2Al＝Al2O3+2Fe。
3.如权利要求1所述制备方法，其特征在于，所述研磨棒采用2或3根棒体，其长度等于或略大于制备的钢管长度。
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CN109822103A (zh) * 2019-03-01 2019-05-31 中南大学 一种高界面结合强度陶瓷外衬钢管的制备方法
CN112377681A (zh) * 2020-11-16 2021-02-19 席赫 一种耐磨输油油管
CN113600816A (zh) * 2021-08-06 2021-11-05 江苏金鹰绝缘管业有限公司 一种高强度陶瓷复合钢管及其加工工艺
CN113735628A (zh) * 2021-09-06 2021-12-03 界首市东城群海彩陶工作室 一种浅浮雕彩陶的生产工艺方法
CN113891959A (zh) * 2019-05-28 2022-01-04 先进材料解决方案私人有限公司 用于生产耐腐蚀合金包覆金属管道的方法

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