CN110436930A - 一种高性能纳米SiC陶瓷及其制备方法和应用 - Google Patents

一种高性能纳米SiC陶瓷及其制备方法和应用 Download PDF

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CN110436930A
CN110436930A CN201910717522.6A CN201910717522A CN110436930A CN 110436930 A CN110436930 A CN 110436930A CN 201910717522 A CN201910717522 A CN 201910717522A CN 110436930 A CN110436930 A CN 110436930A
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詹创添
吴利翔
牛文彬
郭伟明
林华泰
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Guangdong University of Technology
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Abstract

本发明属于陶瓷技术领域,公开了一种高性能纳米SiC陶瓷及其制备方法和应用,所述SiC陶瓷是在氮气气氛下,将聚碳硅烷先升温至200~400℃并保温,然后再升温至600~1400℃裂解后,将裂解产物球磨、造粒后,在保护气氛下,加压10~100MPa,升温至1700~2200℃进行放电等离子烧结制得。所述纳米SiC陶瓷的硬度为30~40GPa,抗弯强度为800~1200MPa,在1200℃下的高温强度为1000~1300MPa。本发明采用放电等离子烧结前驱体裂解后的非晶SiC,本发明的纳米SiC陶瓷致密度高于95~99%,SiC晶粒小于30~100nm,可应用在防弹装甲或核应用领域中。

Description

一种高性能纳米SiC陶瓷及其制备方法和应用
技术领域
本发明属于陶瓷材料技术领域,更具体地,涉及一种高性能纳米SiC陶瓷及其制备方法和应用。
背景技术
SiC陶瓷具有高强、高硬度、耐磨、耐高温、高导热等优异性能,广泛应用于太空反射镜、核反应堆包壳材料以及防弹装甲等。因为SiC作为一种共价键化合物,纯SiC粉体很难烧结致密,通常SiC陶瓷的制备是以高纯SiC粉体为原料、在添加烧结助剂的前提下,通过无压、气压、热压或热等静压烧结制备,但是烧结助剂的添加会影响SiC陶瓷的高温性能以及抗中子辐照等性能,从而阻碍SiC陶瓷的应用。
对于纯SiC陶瓷的制备,目前主要采用化学气相层积方法制备,但是这种方法制备的成本太高,而且无法大规模生产,同时,化学气相层积制备的SiC晶粒粗大,不利于高强度SiC的制备;虽然,也有学者尝试直接用纳米SiC粉体进行热压制备,但是通常制备温度在2400℃以上,过高的温度会使得SiC晶粒过度长大,不利于性能的提高。
发明内容
为了解决上述现有技术存在的不足和缺点,提供一种高性能纳米SiC陶瓷。
本发明的另一目的在于提供上述高性能纳米SiC陶瓷的制备方法。采用SiC前驱体作为原料,低温裂解得到非晶相后,继续在放电等离子烧结设备中快速制备纳米SiC陶瓷。
本发明的再一目的在于提供上述高性能纳米SiC陶瓷的应用。
本发明的目的通过下述技术方案来实现:
一种高性能纳米SiC陶瓷,所述SiC陶瓷是在氮气气氛下,将聚碳硅烷先升温至200~400℃并保温,然后再升温至600~1400℃裂解后,将裂解产物球磨、造粒后,在保护气氛下,加压10~100MPa,升温至1700~2200℃进行放电等离子烧结制得;所述纳米SiC陶瓷的硬度为30~40GPa,抗弯强度为800~1200MPa,在1200℃下的高温强度为1000~1300MPa。
优选地,所述球磨的转数为200~500r/min,所述球磨的时间为8~24h。
优选地,所述升温至200~400℃的速率为1~5℃/min,所述升温至600~1400℃的速率为5~20℃/min。
优选地,所述保温的时间为0.5~2h。
优选地,所述保护气氛为氮气或氩气。
优选地,所述升温至1700~2200℃的速率为100~400℃/min。
优选地,所述烧结的时间为1~10min。
优选地,所述纳米SiC陶瓷的致密度高于95~99%,SiC陶瓷的晶粒30~100nm。
所述的高性能纳米SiC陶瓷的制备方法,包括如下具体步骤:
S1.在氮气气氛下,将聚碳硅烷先升温至200~400℃并保温,然后再升温至600~1400℃进行裂解,得到产物A;
S2.将裂解产物A球磨、造粒后,在保护气氛下,加压10~100MPa,升温至1700~2200℃进行放电等离子烧结,制得高性能纳米SiC陶瓷。
所述的高性能纳米SiC陶瓷在防弹装甲或核应用领域中的应用。
与现有技术相比,本发明具有以下有益效果:
1.本发明采用SiC前驱体聚碳硅烷作为原料,在低温裂解后得到非晶状态下的SiC粉体,非晶粉体具有很好的烧结活性,结合放电等离子烧结方式,可实现高性能纳米SiC陶瓷的快速制备,防止SiC晶粒的长大,从而制备得到高纯和高性能纳米SiC陶瓷。
2.本发明中SiC的制备不需要添加任何烧结助剂,制备的SiC陶瓷具有非常好的高温性能、抗腐蚀和抗辐照性能。
附图说明
图1为实施例1-3中前驱体聚碳硅烷在不同温度裂解的XRD图谱。
具体实施方式
下面结合具体实施例进一步说明本发明的内容,但不应理解为对本发明的限制。若未特别指明,实施例中所用的技术手段为本领域技术人员所熟知的常规手段。除非特别说明,本发明采用的试剂、方法和设备为本技术领域常规试剂、方法和设备。
实施例1
1.制备:
以聚碳硅烷为原料,将聚碳硅烷干压成块体后,以2℃/min升温到200℃保温1h后继续以10℃/min升温到800℃保温1h,得到裂解产物继续进行球磨处理,采用无水乙醇为溶剂,Si3N4磨球为球磨介质,在行星球磨机上进行400r/min运行24h,得到浆料烘干造粒后,放入放电等离子烧结设备中,在氮气下,加压80MPa,以200℃/min升温到1800℃,保温10min,制得纳米SiC陶瓷。
2.性能测试:本实施例制得的SiC陶瓷的致密度为99%。前驱体聚碳硅烷裂解后物相如图1中(a)所示,从图1中可知,此时裂解得到的SiC为非晶态,测得SiC陶瓷的晶粒为60nm,硬度为40GPa,抗弯强度为1200MPa,在1200℃下的高温强度为1300MPa。
实施例2
与实施例1不同的在于:聚碳硅烷前驱体在1000℃下保温1h裂解,裂解产物继续在放电等离子烧结设备中进行2000℃保温1min,加压100MPa,烧结气氛为氩气。
本实施例中聚碳硅烷裂解后物相如图1中(b)所示,此时粉体主要呈非晶状态。制备所得SiC陶瓷的晶粒为80nm,硬度为35GPa,抗弯强度为1000MPa,在1200℃下的高温强度为1200MPa。
实施例3
与实施例1不同的在于:聚碳硅烷前驱体在1200℃下保温1h裂解,裂解产物继续在放电等离子烧结设备中进行2200℃保温10min,加压100MPa,烧结气氛为氩气。
裂解后物相如图1中(c)所示,此时粉体呈部分非晶状态。制备所得SiC陶瓷的晶粒为90nm,硬度为30GPa,抗弯强度为800MPa,在1200℃下的高温强度为1000MPa。
实施例4
与实施例1不同的在于:聚碳硅烷前驱体在600℃下保温1h裂解,裂解后得到粉体继续在放电等离子烧结设备中进行1700℃保温10min,加压50MPa,烧结气氛为氩气。
制备所得SiC陶瓷的晶粒为30nm,硬度为40GPa,抗弯强度为1200MPa,在1200℃下的高温强度为1300MPa。
实施例5
与实施例1不同的在于:聚碳硅烷前驱体在1400℃下保温1h裂解,裂解后得到粉体继续在放电等离子烧结设备中进行2000℃保温10min,加压100MPa,烧结气氛为氩气。
制备所得SiC陶瓷的晶粒为80nm,硬度为30GPa,抗弯强度为1000MPa,在1200℃下的高温强度为1200MPa。
上述实施例为本发明较佳的实施方式,但本发明的实施方式并不受上述实施例的限制,其他的任何未背离本发明的精神实质与原理下所作的改变、修饰、替代、组合和简化,均应为等效的置换方式,都包含在本发明的保护范围之内。

Claims (10)

1.一种高性能纳米SiC陶瓷,其特征在于,所述SiC陶瓷是在氮气气氛下,将聚碳硅烷先升温至200~400℃并保温,然后再升温至600~1400℃裂解后,将裂解产物球磨、造粒后,在保护气氛下,加压10~100MPa,升温至1700~2200℃进行放电等离子烧结制得;所述纳米SiC陶瓷的硬度为30~40GPa,抗弯强度为800~1200MPa,在1200℃下的高温强度为1000~1300MPa。
2.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述球磨的转数为200~500r/min,所述球磨的时间为8~24h。
3.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述升温至200~400℃的速率为1~5℃/min,所述升温至600~1400℃的速率为5~20℃/min。
4.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述保温的时间为0.5~2h。
5.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述保护气氛为氮气或氩气。
6.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述升温至1700~2200℃的速率为100~400℃/min。
7.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述烧结的时间为1~10min。
8.根据权利要求1所述的高性能纳米SiC陶瓷,其特征在于,所述纳米SiC陶瓷的致密度高于95~99%,SiC陶瓷的晶粒30~100nm。
9.根据权利要求1-8任一项所述的高性能纳米SiC陶瓷的制备方法,其特征在于,包括如下具体步骤:
S1.在氮气气氛下,将聚碳硅烷先升温至200~400℃并保温,然后再升温至600~1400℃进行裂解,得到产物A;
S2.将裂解产物A球磨、造粒后,在保护气氛下,加压10~100MPa,升温至1700~2200℃进行放电等离子烧结,制得高性能纳米SiC陶瓷。
10.权利要求1-8任一项所述的高性能纳米SiC陶瓷在防弹装甲或核工业领域中的应用。
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CN112062574A (zh) * 2020-08-19 2020-12-11 广东工业大学 一种高性能纳米碳化硅陶瓷及其制备方法和应用
CN112062572A (zh) * 2020-08-19 2020-12-11 广东工业大学 一种高致密度的碳化硅陶瓷及其制备方法和应用
CN114315361A (zh) * 2021-12-21 2022-04-12 燕山大学 纳米晶碳化硅超硬块材及其制备方法
CN115724664A (zh) * 2022-10-28 2023-03-03 中国科学院上海硅酸盐研究所 一种两步烧结快速制备MCMBs/SiC复合材料的方法
CN115724664B (zh) * 2022-10-28 2023-11-10 中国科学院上海硅酸盐研究所 一种两步烧结快速制备MCMBs/SiC复合材料的方法
CN115784747A (zh) * 2022-11-29 2023-03-14 郑州大学 聚合物转化可控碳改性SiC陶瓷靶材的制备方法
CN115784747B (zh) * 2022-11-29 2024-01-09 郑州大学 聚合物转化可控碳改性SiC陶瓷靶材的制备方法

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Application publication date: 20191112