CN109020504A - 一种镁碳化硅砖及其生产方法 - Google Patents

一种镁碳化硅砖及其生产方法 Download PDF

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CN109020504A
CN109020504A CN201810982571.8A CN201810982571A CN109020504A CN 109020504 A CN109020504 A CN 109020504A CN 201810982571 A CN201810982571 A CN 201810982571A CN 109020504 A CN109020504 A CN 109020504A
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silicon carbide
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杨敬彪
张义先
王振宇
王新杰
杨庆余
王健骁
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Haicheng Lear Meg Materials Co Ltd Sita
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Abstract

本发明提供了一种镁碳化硅砖及其生产方法,所述的镁碳化硅砖由下列重量份数的原料制备而成:0<粒度≤0.088mm的97高纯镁砂25‑30份,0<粒度≤1mm的97高纯镁砂15‑25份,1mm<粒度≤3mm的97高纯镁砂25‑35份,3mm<粒度≤5mm的97高纯镁砂5‑15份;96碳化硅细粉0~5份,结合剂2‑4份。本发明引入适量的碳化硅,大大提高了镁质砖的抗酸性渣侵蚀能力。应用于玻璃窑蓄热室上层格子体,代替目前的98镁砖、镁锆砖、铬刚玉砖,实现无铬化。本发明物料中不含铬,非氧化物碳化硅,降低了镁质材料的热膨胀系数,大大提高了抗热震性能,抗酸性渣的侵蚀能力,其耐磨性好,高温强度大,热导率高,热膨胀系数小是玻璃窑蓄热室比较理想的耐材。

Description

一种镁碳化硅砖及其生产方法
技术领域
本发明涉及耐火材料技术领域,尤其涉及一种镁碳化硅砖及其生产方法。
背景技术
随着玻璃窑用石油焦燃料的推广,燃烧产物中SiO3、V2O5加剧了玻璃窑蓄热室耐材的损毁速度,对耐材提出了更高要求。
在氧化气氛中,V2O5与CaO反应产生低熔点的钒酸钙,在稍有降低的氧化气氛中,产生挥发性的钒酸钙。氧化镁中的结合相失去CaO,CaO/SiO2比变化到高氧化硅水平,低熔物硅酸钙镁、镁蔷微辉石和钙镁橄榄石出现。
SiC分子量为40,密度3.22kg/m3,莫氏硬度9.0~9.5。有立方晶系β-SiC和六方晶系的α-SiC。β-SiC只有一种晶型,α-SiC有多种晶型。热膨胀系数4.7×10-6,热导率高(20℃时为58.6W/m℃),并随温度升高而降低。1000℃开始分解,1700℃时分解作用进行迅速。氧化速度随时间而减慢。
非氧化物碳化硅与氧化镁不互溶,在高温下稳定。碳化硅的引入,可以降低镁质材料膨胀系数,而且可以提高镁质材料对石油焦燃烧产物中SiO3、V2O5的抗侵蚀侵蚀能力。
发明内容
本发明的目的在于提供一种镁碳化硅砖及其生产方法,用于玻璃窑蓄热室上层格子体,其耐磨性和耐侵蚀性好,高温强度大,热导率高,热膨胀系数小,热震稳定性好。
为了达到上述目的,本发明采用以下技术方案实现:
一种镁碳化硅砖,是由下列重量份数的原料制备而成:0<粒度≤0.088mm的97高纯镁砂25-30份,0<粒度≤1mm的97高纯镁砂15-25份,1mm<粒度≤3mm的97高纯镁砂25-35份,3mm<粒度≤5mm的97高纯镁砂5-15份;96碳化硅细粉0~5份,结合剂2-4份。
所述结合剂为纸浆废液。
所述96碳化硅细粉的粒径为325目。
一种镁碳化硅砖的生产方法,包括如下步骤:
1)原料破碎、筛分、细磨:97高纯镁砂经破碎,粉碎成0<粒度≤0.088mm、0<粒度≤1mm、1mm<粒度≤3mm、3mm<粒度≤5mm的颗粒;
2)配料:将原料按照上述重量份数称重备用;先将96碳化硅细粉与10-20份0<粒度≤1mm的97高纯镁砂颗粒进行预混;
3)混练:先加入1mm<粒度≤3mm、3mm<粒度≤5mm和剩余的0<粒度≤1mm的97高纯镁砂颗粒,干混3~5min,然后加入结合剂,再混3~5min,加入步骤2)中得到预混料和0<粒度≤0.088mm的97高纯镁砂颗粒,混8~12min,然后出料;
4)机压成型:采用630吨压砖机成型,砖坯体密≥3.00g/cm3
5)干燥:干燥温度为100~120℃,干燥10h以上;
6)烧成:弱氧化气氛烧成,烧成温度1400~1600℃,烧成时间2~4h。
与现有技术相比,本发明的有益效果是:
1)本发明引入适量的碳化硅,其中碳化硅与镁砂不互溶,不生成低熔点矿物,碳化硅可能纯在部分氧化,生成SiO2,SiO2与MgO生成镁橄榄石;碳化硅橄榄石矿物相同时存在,大大提高了镁质砖的抗酸性渣侵蚀能力。应用于玻璃窑蓄热室上层格子体,代替目前的98镁砖、镁锆砖、铬刚玉砖,实现无铬化。
2)本发明物料中不含铬,非氧化物碳化硅引入,降低了镁质材料的热膨胀系数,大大提高了抗热震性能,抗酸性渣的侵蚀能力,其耐磨性好,高温强度大,热导率高,热膨胀系数小是玻璃窑蓄热室比较理想的耐材。
具体实施方式
以下对本发明的具体实施方式作进一步说明:
一种镁碳化硅砖,是由下列重量份数的原料制备而成:0<粒度≤0.088mm的97高纯镁砂20-25份,0<粒度≤1mm的97高纯镁砂15-25份,1mm<粒度≤3mm的97高纯镁砂25-35份,3mm<粒度≤5mm的97高纯镁砂5-15份;96碳化硅细粉0-5份,,结合剂2-4份。
所述结合剂为纸浆废液。
所述96碳化硅细粉的粒径为325目。
一种镁碳化硅砖的生产方法,包括如下步骤:
1)原料破碎、筛分、细磨:97高纯镁砂经破碎,粉碎成0<粒度≤0.088mm、0<粒度≤1mm、1mm<粒度≤3mm、3mm<粒度≤5mm的颗粒;
2)配料:将原料按照上述重量份数称重备用;先将96碳化硅细粉与10-20份0<粒度≤1mm的97高纯镁砂颗粒进行预混;
3)混练:先加入1mm<粒度≤3mm、3mm<粒度≤5mm和剩余的0<粒度≤1mm的97高纯镁砂颗粒,干混3~5min,然后加入结合剂,再混3~5min,加入步骤2)中得到预混料和0<粒度≤0.088mm的97高纯镁砂颗粒,混8~12min,然后出料;
4)机压成型:采用630吨压砖机成型,砖坯体密≥3.00g/cm3
5)干燥:干燥温度为100~120℃,干燥10h以上;
6)烧成:弱氧化气氛烧成,烧成温度1400~1600℃,烧成时间2~4h。
本发明主要原料指标见表1:
表1: 单位:wt%
烧成产品的理化指标见表2:
表2:
项目 典型值
MgO,% 92.2
SiO2,% 0.75
CaO,% 1.20
Al2O3,% 0.20
SiC,% 4.8
显气孔率,% 17.0
体密密度,g/cm3 2.95
常温耐压强度,MPa 60.0
热震稳定性,(1100℃,水冷)次 10
实施例配方见表3:
表3
实施例产品的生产方法如下:
1)原料破碎、筛分、细磨:97高纯镁砂经破碎,粉碎成0<粒度≤0.088mm、0<粒度≤1mm、1mm<粒度≤3mm、3mm<粒度≤5mm的颗粒;
2)配料:将原料按照上述重量份数称重备用;先将96碳化硅细粉与10-20份0<粒度≤1mm的97高纯镁砂颗粒进行预混;
3)混练:先加入1mm<粒度≤3mm、3mm<粒度≤5mm和剩余的0<粒度≤1mm的97高纯镁砂颗粒,干混3~5min,然后加入结合剂,再混3~5min,加入步骤2)中得到预混料和0<粒度≤0.088mm的97高纯镁砂颗粒,混8~12min,然后出料;
4)机压成型:采用630吨压砖机成型,砖坯体密≥3.00g/cm3
5)干燥:干燥温度为100~120℃,干燥10h以上;
6)烧成:弱氧化气氛烧成,烧成温度1400~1600℃,烧成时间2~4h。

Claims (4)

1.一种镁碳化硅砖,其特征在于,由下列重量份数的原料制备而成:0<粒度≤0.088mm的97高纯镁砂20-25份,0<粒度≤1mm的97高纯镁砂15-25份,1mm<粒度≤3mm的97高纯镁砂25-35份,3mm<粒度≤5mm的97高纯镁砂5-15份;96碳化硅细粉0~5份,结合剂2-4份。
2.根据权利要求1所述的一种镁碳化硅砖,其特征在于,所述结合剂为纸浆废液。
3.根据权利要求1所述的一种镁碳化硅砖,其特征在于,所述96碳化硅细粉的粒径为325目。
4.一种如权利要求1所述的镁碳化硅砖的生产方法,其特征在于,包括如下步骤:
1)原料破碎、筛分、细磨:97高纯镁砂经破碎,粉碎成0<粒度≤0.088mm、0<粒度≤1mm、1mm<粒度≤3mm、3mm<粒度≤5mm的颗粒;
2)配料:将原料按照上述重量份数称重备用;先将96碳化硅细粉与10-20份0<粒度≤1mm的97高纯镁砂颗粒进行预混;
3)混练:先加入1mm<粒度≤3mm、3mm<粒度≤5mm和剩余的0<粒度≤1mm的97高纯镁砂颗粒,干混3~5min,然后加入结合剂,再混3~5min,加入步骤2)中得到预混料和0<粒度≤0.088mm的97高纯镁砂颗粒,混8~12min,然后出料;
4)机压成型:采用630吨压砖机成型,砖坯体密≥3.00g/cm3
5)干燥:干燥温度为100~120℃,干燥10h以上;
6)烧成:弱氧化气氛烧成,烧成温度1400~1600℃,烧成时间2~4h。
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CN112500130A (zh) * 2020-12-07 2021-03-16 海城利尔麦格西塔材料有限公司 一种硅钙钡复相结合碳化硅的镁碳砖及其制造方法
CN113045292A (zh) * 2021-03-22 2021-06-29 河北北方窑业工程有限公司 一种大于等于2100℃超高温竖窑的高纯镁砖及其制造方法
CN116730731A (zh) * 2023-05-09 2023-09-12 武汉科技大学 一种碳化硅基陶瓷蓄热体及其制备方法

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Publication number Priority date Publication date Assignee Title
CN112500130A (zh) * 2020-12-07 2021-03-16 海城利尔麦格西塔材料有限公司 一种硅钙钡复相结合碳化硅的镁碳砖及其制造方法
CN113045292A (zh) * 2021-03-22 2021-06-29 河北北方窑业工程有限公司 一种大于等于2100℃超高温竖窑的高纯镁砖及其制造方法
CN116730731A (zh) * 2023-05-09 2023-09-12 武汉科技大学 一种碳化硅基陶瓷蓄热体及其制备方法
CN116730731B (zh) * 2023-05-09 2024-05-28 武汉科技大学 一种碳化硅基陶瓷蓄热体及其制备方法

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Application publication date: 20181218