CAJ | 학술논문

以ZrC,SiC,石墨为原料,采用热压烧结法制备了ZrC-SiC-C_g三元复相陶瓷,研究了石墨及其用量对所制备陶瓷材料的微观结构和力学性能的影响.结果表明:石墨的加入有效地促进了ZrC-SiC-C_g复相陶瓷的烧结,在添加约10%(体积分数, 下同)石墨时,密度达到最大.同时复相陶瓷表面随着石墨含量的增加,逐渐变得粗糙,即由于石墨与基体的结合较弱使材料表面出现剥落现象.力学性能分析表明,材料的抗弯强度在石墨含量小于10%时并未明显降低,其断裂韧性随着石墨量的增加呈现先增加后降低的趋势,当石墨含量为10%时,断裂韧性出现最大值4.29 MPa·m~(1/2).材料的断裂方式是沿晶和穿晶断裂相结合.
이ZrC,SiC,석묵위원료,채용열압소결법제비료ZrC-SiC-C_g삼원복상도자,연구료석묵급기용량대소제비도자재료적미관결구화역학성능적영향.결과표명:석묵적가입유효지촉진료ZrC-SiC-C_g복상도자적소결,재첨가약10%(체적분수, 하동)석묵시,밀도체도최대.동시복상도자표면수착석묵함량적증가,축점변득조조,즉유우석묵여기체적결합교약사재료표면출현박락현상.역학성능분석표명,재료적항만강도재석묵함량소우10%시병미명현강저,기단렬인성수착석묵량적증가정현선증가후강저적추세,당석묵함량위10%시,단렬인성출현최대치4.29 MPa·m~(1/2).재료적단렬방식시연정화천정단렬상결합.
In the present work, ZrC-SiC-C_g composites were prepared by hot pressing using ZrC, SiC and graphite as the starting materials. Effect of the graphite and its content on the microstructure and mechanical properties of the fabricated ceramic materials were investigated. Results show that the addition of graphite is efficient in promoting the sinterability of ZrC-SiC-C_g composites. The relative density of composites reaches to a maximal value when the content of graphite is 10vol.%. Meanwhile, the surface of composites gradually become coarse with increasing graphite content, which is attributed to the weaker bonding between graphite and matrix, leading to the occurrence of grain-pullout. The flexural strength is not obviously decreased when the content of graphite is increased to 10vol.%. The fracture toughness firstly increases and then decreases with increasing graphite content, and the highest fracture toughness, 4.29 MPam~(1/2), is obtained with 10vol.% graphite. The fracture surface of composites show a mixture mode of transgranular and intergranular fracture.