新型耐火材料试条模具的研究

New Die Designing for Refractory Testing Bar

半干法压制成型是最常见的耐火材料制品成型工艺之一。在压制过程中,由于物料脊性、散松、没有足够的水分和结合剂,必须施以较大的压力,借助于压力的作用使坯料的颗粒重新分布,在机械结合力、静电引力以及摩擦力的作用下,坯料颗粒紧密结合,排出空气,在模具的型腔内形成预定尺寸和形状并具有一定强度的制品。 通常在其它工艺条件(如物料品种、颗粒级配、水分含量和结合剂等)相同时,压制压力增高,坯体的气孔率下降,密度增大,强度随之提高。显然,压力与气孔率、密度之间存在密切的联系。

Considering deformation problems of side wall of the traditional four-piece-die for dust pressing of refractory testing bar, a new combinatory die was designed based on the strength theory of high pressure vessels. This die can avoid deformation even at very high pressure up to 200 MPa due to its reasonable stress distribution.