高导热氮化硅陶瓷用烧结助剂的研究进展

王月隆; 吴昊阳; 贾宝瑞; 张一铭; 张智睿; 刘昶; 田建军; 秦明礼

doi:10.19591/j.cnki.cn11-1974/tf.2021070001

高导热氮化硅陶瓷用烧结助剂的研究进展

doi: 10.19591/j.cnki.cn11-1974/tf.2021070001

1.
北京科技大学新材料技术研究院, 北京 100083

基金项目: 国家自然科学基金资助项目（51574031，51574030，51574029，51604240）；河北省重点研究发展项目（20311001D）；北京市自然科学基金资助项目（2202031，2174079，2162027）；中央高校基础研究基金资助项目（FRF-TP-19-015A3，FRF-TP-20-100A1Z，FRF-TP-19-003C2，FRF-TP-17-034A2）；USTB–NTUT联合研究项目（06310061）；湖南省教育厅科研经费资助项目（18A196）；北京科技大学顺德研究生院博士后研究基金资助项目（2020BH014）

详细信息

通讯作者:
wuhaoyang@ustb.edu.cn (吴昊阳)

E-mail: qinml@mater.ustb.edu.cn (秦明礼)

中图分类号: TF123; TQ174.7
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出版历程
- 收稿日期: 2021-10-26
- 刊出日期: 2024-02-28

Research progress on sintering additive used for high thermal conductivity silicon nitride ceramics

1.
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China

More Information

Corresponding author: wuhaoyang@ustb.edu.cn (WU H Y); E-mail: qinml@mater.ustb.edu.cn (QIN M L)

摘要

摘要: 氮化硅被认为是综合性能最好的陶瓷材料，良好的导热性和优异的力学性能使其成为大功率电子器件用陶瓷基板的主流材料，在纯电动/混合电动汽车中得到广泛应用。烧结助剂对氮化硅烧结活性、微观组织和第二相成分及含量影响较大，进而影响陶瓷导热性能，选择合适的烧结助剂对制备高导热氮化硅陶瓷非常重要。本文整理了目前制备高导热氮化硅陶瓷用烧结助剂研究现状，分析了烧结助剂对氮化硅陶瓷导热性及力学性能的影响，并对烧结助剂未来的研究方向和发展趋势提出了展望。
- 氮化硅 /
- 陶瓷 /
- 烧结助剂 /
- 导热性 /
- 力学性能
Abstract: Silicon nitride (Si₃N₄) is considered to be the best ceramic material for the comprehensive properties. High thermal conductivity and the excellent mechanical properties make it widely used as the ceramic substrate in electric vehicles and hybrid electric vehicles (EV/HEV). Sintering additives have the great influence on the sintering activity, microstructure, and the second phase composition of silicon nitride, and then affect the thermal conductivity of ceramics. Selecting the suitable sintering additives is very important for the preparation of high thermal conductivity silicon nitride ceramics. The research status of sintering additives used for the preparation of high thermal conductivity silicon nitride ceramics was summarized in this paper, the influence of sintering additives on the thermal conductivity and mechanical properties of silicon nitride ceramics was analyzed, and the future research direction and development trend of sintering additives were put forward.
- silicon nitride /
- ceramics /
- sintering additives /
- thermal conductivity /
- mechanical properties

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图 1 液相烧结组织形貌变化示意图^[20]

Figure 1. Schematic of the microstructure changes during the liquid phase sintering^[20]

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图 2 MgO和Al₂O₃对氮化硅陶瓷导热性能的影响^[23]

Figure 2. Effect of the MgO and Al₂O₃ content on the thermal conductivity of Si₃N₄ ceramics^[23]

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图 3 不同稀土氧化物烧结助剂形成第二相厚度^[35]

Figure 3. HRTEM micrographs of the grain boundaries in Si₃N₄ with the different sintering additives^[35]

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图 4 稀土离子半径与氮化硅热导率的关系^[36]

Figure 4. Relationship between the thermal conductivity of Si₃N₄ and the ion radius of rare earth elements^[36]

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图 5 MgO粒径对氮化硅陶瓷微观形貌的影响^[43]：（a）、（c）D₅₀=5.9 μm；（b）、（d）D₅₀=1.6 μm

Figure 5. Effect of MgO particle size on micromorphology of the silicon nitride ceramics^[43]: (a), (c) D₅₀=5.9 μm; (b), (d) D₅₀=1.6 μm

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图 6 烧结助剂摩尔分数对氮化硅陶瓷热导率的影响^[45]：（a）2%Y₂O₃−xMgO，x=0～8%；（b）yY₂O₃−5%MgO，y=0～5%

Figure 6. Thermal conductivities of the sintered Si₃N₄ ceramics with the different sintering additives^[45]: (a) 2%Y₂O₃−xMgO，x=0～8%; (b) yY₂O₃−5%MgO，y=0～5%

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图 7 不同保温时间下氮化硅陶瓷微观形貌图^[46]：（a）、（b）3 h；（c）、（d）60 h

Figure 7. SEM images of the Si₃N₄ ceramics obtained at 1900 ℃ for the various holding time^[46]: (a), (b) 3 h; (c), (b) 60 h

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图 8 晶格氧含量与氮化硅陶瓷热导率的关系^[48]

Figure 8. Relationship between the lattice oxygen contents and the thermal conductivities for sintered Si₃N₄ ceramics^[48]

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图 9 经过烧结处理后3YM样品能谱分析^[52]

Figure 9. Energy spectrum analysis of the elements distribution in sample 3YM after sintering^[52]

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图 10 氮化硅陶瓷扫描电子显微形貌^[64]：（a）、（c）SN；（b）、（d）SNC

Figure 10. SEM inmages of the Si₃N₄ ceramics samples^[64]: (a), (c) SN; (b), (d) SNC

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图 11 氮化硅基板热导率随温度的变化（SN1, SNN10 , SNN15, and SNN20）^[65]

Figure 11. Temperature dependence of thermal conductivities of the Si₃N₄ substrate (SN1, SNN10 , SNN15, and SNN20)^[65]

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表 1 各种陶瓷基板的物理性能

Table 1. Physical properties of the ceramic substrates

材料	热导率 / （W m⁻¹·K⁻¹）	热膨胀系数 / （×10⁻⁶ K⁻¹）	介电常数（1 MHz）	电场强度 / （kV·mm⁻¹）	断裂韧性 / （MPa·m^1/2）	抗弯强度 / MPa	可靠性* / 次
Al₂O₃	30	7.2	9.7	10	3.0	400	300
BeO	200～250	7.5	6.7	10	3.3	250	—
AlN	150～200	3.5	8.9	15	2.7	350	200
Si₃N₄	90	3.2	9.4	＞20	6.0～8.0	600～800	＞5000
*注：可靠性是指在−40～+150 ℃条件下循环，材料不破坏次数。

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表 2 不同烧结助剂下物相强度^[29]

Table 2. Phase intensity with the different sintering additives^[29]

烧结助剂	烧结时间 / h	物相（强度）*
La₂O₃	4	β-Si₃N₄(s), α-Si₃N₄(s), La₂₀N₄Si₁₂O₄₈(m), La₂SiO₅(w)
La₂O₃	16	β-Si₃N₄(vs), La₂₀N₄Si₁₂O₄₈(m), La₂SiO₅(w)
Nd₂O₃	4	β-Si₃N₄(vs), Nd₂Si₃O₃N₄(w), Nd₄Si₃O₁₂ (w)
Nd₂O₃	16	β-Si₃N₄(vs), Nd₂Si₃O₃N₄(w), Nd₄Si₃O₁₂ (w)
Gd₂O₃	4	β-Si₃N₄(vs), Gd₂₀N₄Si₁₂O₄₈(m), Gd₂Si₃O₃N₄(vw)
Gd₂O₃	16	β-Si₃N₄(vs), Gd₂₀N₄Si₁₂O₄₈(m), Gd₂Si₃O₃N₄(w)
Y₂O₃	4	β-Si₃N₄(vs), Y₂₀N₄Si₁₂O₄₈(m), Y₂Si₃O₃N₄(w)
Y₂O₃	16	β-Si₃N₄(vs), Y₂₀N₄Si₁₂O₄₈(m), Y₂Si₃O₃N₄(w)
Yb₂O₃	4	β-Si₃N₄(vs), Yb₂Si₂N₂O₇(s)
Yb₂O₃	16	β-Si₃N₄(vs), Yb₂Si₂N₂O₇(s)
Sc₂O₃	4	β-Si₃N₄(vs), Sc₂SiO₅(vw)
Sc₂O₃	16	β-Si₃N₄(vs), Sc₂SiO₅(vw)
*注：vs为非常强，s为强，m为中等，w为弱，vw为非常弱

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表 3 不同稀土氧化物烧结助剂对氮化硅陶瓷性能的影响^[29]

Table 3. Properties of the Si₃N₄ ceramics with the different sintering additives^[29]

烧结助剂	离子半径 / nm	烧结时间 / h	密度 / (g·cm⁻³)	热导率 / (W·m⁻¹·K⁻¹)		晶格氧质量分数 / %
烧结助剂	离子半径 / nm	烧结时间 / h	密度 / (g·cm⁻³)	平行	垂直	晶格氧质量分数 / %
La₂O₃	0.106	4	3.35	28.1	31.6	0.279±0.037
La₂O₃	0.106	16	3.33	51.1	64.9	0.116±0.006
Nd₂O₃	0.100	4	3.39	64.1	81.6	0.094±0.005
Nd₂O₃	0.100	16	3.38	72.2	97.9	0.092±0.013
Gd₂O₃	0.094	4	3.42	78.7	100.7	0.076±0.002
Gd₂O₃	0.094	16	3.42	81.6	106.9	0.069±0.013
Y₂O₃	0.089	4	3.25	82.9	104.6	0.076±0.001
Y₂O₃	0.089	16	3.28	82.7	105.8	0.063±0.002
Yb₂O₃	0.086	4	3.46	86.1	115.0	0.061±0.002
Yb₂O₃	0.086	16	3.44	88.6	114.7	0.080±0.006
Sc₂O₃	0.073	4	3.21	84.9	100.8	0.085±0.004
Sc₂O₃	0.073	16	3.19	89.6	106.3	0.077±0.003

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表 4 添加不同种类稀土氢化物为烧结助剂制备得到氮化硅陶瓷的热导率

Table 4. Thermal conductivity of Si₃N₄ doped with the different rare-earth hydride as the sintering additives

烧结助剂	烧结时间 / h	热导率 / (W·m⁻¹·K⁻¹)
YH₂^[52]	4	101.80
	12	123.00
	24	131.60
GdH₂^[54]	4	98.07
	12	119.07
	24	134.90
YbH₂^[55]	4	100.20
	12	118.90
	24	131.15

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