氮化硅陶瓷注射成型体脱脂过程的研究

Study on Binder Extraction Processing for Injection Moulded Body of Si_3N_4

陶瓷注射成型是制备复杂形状陶瓷部件的一种有效方法。在这一陶瓷制备技术中,注射成型体的脱脂过程是关键一环。本文针对尺寸较大、形状复杂的陶瓷涡轮转子、研究了坯体中有机物排出的脱脂过程。结果表明:在低温段(RT～300℃左右),埋粉性质对脱脂速率和坯体质量影响显著,而高温段有机物的排除主要以裂解形式,脱脂气氛和压力起着重要作用;对于尺寸较大,形状复杂的陶瓷注射坯体在氮气中加压脱脂更为有利。

Ceramic injection moulding is an effictive methd to prapare ceramic parts with complex shape. The organic binder extraction of injection moulded body is key step in this fabricating technology. In present paper, the process of binder extraction was studied on turbine rotor with large size and complicated shape. The experimental results show that properties of powder embeded outstandingly affect the debinder speed and the body quality in the low temperature step (room temperature to about 300℃). Organic binder mainly are removed from the body by the thermal degradation, and the atomosphere and pressure in furnace are very important in the high temperature step. It turn out that binder extraction is more favourable in the nitrogen atmosphere to the body with large size and complex shap.