多晶YAG陶瓷的制备及力学性能

PREPARATION AND MECHANICAL PROPERTIES OF POLYCRYSTALLINE YTTRIUM ALUMINUM GARNET

本实验采用共沉淀方法制备YAG微粉 ,Al和Y元素分布均匀 ,在 90 0℃煅烧 2h即可全部转变为YAG粉体 ,无过渡相 .15 0 0℃热压 1h可获得致密烧结体 ,其抗弯强度为 2 45MPa ,断裂韧性为 2 .0MPa·m1 /2 ,晶粒大小为 3～ 6μm ;14 0 0℃放电等离子烧结 5min可获得相对密度为 93 %的烧结体 ,其抗弯强度为 3 4 8MPa,断裂韧性为 2 .1MPa·m1 /2 ,晶粒大小为 1～ 2 μm .

YAG powder was prepared by co-precipitation method, and Al and Y elements were uniformly distributed in powder. After calcination at 900°C for 2 h, pure YAG phases can be obtained. The powder has good sintering ability, and dense bodies could be obtained by hot-pressing at 1500°C for 1 h. Its bending strength and fracture toughness are 245 MPa and 2.0 Mpa&middotm1/2, respectively. Through SEM observation, the grain size is about 3-6 μm. Spark plasma sintering was also employed to produce sintering body, 93% relative density could be obtained at 1400°C for 5 min. Its bending strength is 348 MPa, and fracture toughness is 2.1 MPa&middotm1/2. Its grain size is about 1-2 μm.