摘要
ZrC陶瓷在高温高压环境下具有较好应用前景,但其韧性低限制了其应用。Zr-Al-C三元层状化合物具有良好的力学性能,因此本文以Zr粉、Al粉、C粉为原料,采用放电等离子烧结技术制备出单相致密的Zr_(3)Al_(3)C_(5)陶瓷,研究了Zr_(3)Al_(3)C_(5)化合物的反应过程和力学性能。结果表明:合成温度为700℃,生成了大量的Zr-Al金属间化合物;当温度达到900℃时,ZrAl3化合物转变为Zr_(2)Al-(3)和ZrAl_(2),同时生成了Al4C3和ZrC化合物;当温度为1300℃时,出现了层状的Zr_(3)Al_(3)C_(5)化合物,但由于Al极易熔融使得局部不均匀,导致在1500℃时形成了Zr_(2)Al-(3)C4化合物,烧结温度达到1700℃时制备出单相致密的Zr_(3)Al_(3)C_(5)陶瓷,其硬度和杨氏模量分别达到了10.9 GPa和310 GPa,断裂韧性为3.8MPa·m^(1/2)±0.16MPa·m^(1/2),这是因为层状结构和细长的晶粒结构使得断裂过程中能量耗散,提高了其断裂韧性。
ZrC ceramics have good prospects for application in high-temperature and high-pressure environments,but their low toughness limits their practical applications.Zr-Al-C ternary layered compounds have good mechanical properties,so in this paper,single-phase dense Zr_(3)Al_(3)C_(5)ceramics were prepared by spark plasma sintering using Zr,Al and C powder as raw materials,and the reaction process and mechanical properties of Zr_(3)Al_(3)C_(5)compounds were investigated.The results showed that at 700℃,a large amount of Zr-Al intermetallic compounds were generated.At 900℃,the ZrAl3 compounds were transformed into Zr_(2)Al-(3)and ZrAl_(2),and Al4C3 and ZrC compounds were formed simultaneously.When the temperature reached 1300℃,the Zr_(3)Al_(3)C_(5)compounds appeared,but during the sintering process,Zr_(2)Al-(3)C4 compounds were generated due to the local inhomogeneity caused by the extremely easy melting of Al.When the temperature reached 1700℃,single-phase dense Zr_(3)Al_(3)C_(5)ceramics were prepared.The hardness and Young's modulus of Zr_(3)Al_(3)C_(5)ceramics reached 10.9 GPa and 310 GPa,respectively,and the fracture toughness was 3.8 MPa·m^(1/2)±0.16 MPa·m^(1/2).The lamellar structure and elongated grain structure allowed the energy dissipation during fracture and improved the fracture toughness.
作者
郭启龙
刘荣浩
应豪
华亮
GUO Qi-Long;LIU Rong-Hao;YING Hao;HUA Liang(School of Civil Engineering,Northwest Minzu University,Lanzhou 730124,China;Key Laboratory of New Building Materials and Building Energy Efficiency of Gansu Province,Lanzhou 730124,China)
出处
《现代技术陶瓷》
CAS
2024年第1期160-168,共9页
Advanced Ceramics
基金
国家自然科学基金(52162011)
中央高校基本科研业务费专项资金项目(31920230178)
甘肃省自然科学基金(20JR5RA510)
