Effect of silicon nitride addition on the thermal and mechanical properties of magnesium silicon nitride ceramics
Effect of silicon nitride addition on the thermal and mechanical properties of magnesium silicon nitride ceramics
复制标题
DOI：
10.1016/s0955-2219(03)00374-1
复制
发表时间：
2004-06
影响因子：
5.7
通讯作者：
S. Tanaka;K. Itatani;H. Hintzen;A. Delsing;I. Okada
中科院分区：
文献类型：
--
作者：
S. Tanaka;K. Itatani;H. Hintzen;A. Delsing;I. Okada
使用热压技术研究了氮化硅 (Si3N4) 添加对氮化硅镁 (MgSiN2) 粉末烧结的影响。添加 1、4 和 9 mol% Si3N4 [烧结助剂：1 mol% 氧化镱 (Yb2O3)] 的 MgSiN2 粉末压块在氮气 (N2) 气氛和 75 MPa 的压力下在 1550 至 1800 °C 的温度下热压 90 分钟。添加 4 mol% Si3N4 的 MgSiN2 复合体在 1600 °C 下热压 90 分钟后，其相对密度达到最大值（98.6%），尽管在其他热压温度下添加 Si3N4 会降低相对密度。添加 4 mol% 和 9 mol% Si3N4 的 MgSiN2 样品在 1600 °C 下热压 90 分钟后获得了最大断裂韧性（6.6 MPa·m1/2）。该值比未添加Si3N4的MgSiN2试件（2.6 MPa·m1/2）高2.5倍。断裂韧性的提高似乎是由于 Si3N4 晶粒的伸长，这是在热压过程中液相存在的情况下发生的。添加 9 mol% Si3N4 的 MgSiN2 样品在 1750 °C 下热压 90 分钟后，其热导率增加至 34.1 W m−1K−1，据我们所知，这是迄今为止报道的 MgSiN2 陶瓷值中的最高值。
The effect of silicon nitride (Si3N4) addition on the sintering of magnesium silicon nitride (MgSiN2) powder has been examined using a hot-pressing technique. The MgSiN2powder compacts with 1, 4, and 9 mol% of Si3N4addition [sintering aid: 1 mol% ytterbium oxide (Yb2O3)] were hot-pressed at a temperature between 1550 and 1800 °C for 90 min in a nitrogen (N2) atmosphere under the pressure of 75 MPa. The relative density of a MgSiN2compact with 4 mol% of Si3N4addition hot-pressed at 1600 °C for 90 min showed a maximum (98.6%), although the relative density was reduced by the addition of Si3N4at other hot-pressing temperatures. The maximum fracture toughness (6.6 MPa·m1/2) was achieved for the MgSiN2specimen with 4 and 9 mol% of Si3N4addition hot-pressed at 1600 °C for 90 min. This value was 2.5 times higher than that of MgSiN2specimen without Si3N4addition (2.6 MPa·m1/2). The improvement of the fracture toughness appeared to be due to the elongation of the Si3N4grains, which had occurred in the presence of a liquid phase during the hot pressing. The thermal conductivity of the MgSiN2specimen with 9 mol% of Si3N4addition hot-pressed at 1750 °C for 90 min increased to 34.1 W m−1K−1, which is to our knowledge, the highest among the values so far reported for MgSiN2ceramics.