Effect of molding process on tribology and mechanical properties of porous PI materials

Abstract

In order to explore the influence of cold-pressing and constant-volume sintering molding process on the friction and mechanical properties of porous polyimide (PI) materials, the effects of density, sintering temperature and holding time on the oil content, friction coefficient, tensile strength and impact strength of porous PI materials were studied by orthogonal experimental design method.By comprehensively considering the friction coefficient and impact strength after centrifuging oil, the molding process of the porous PI material was optimized. The experimental results show that as the density decreases, the surface holes of the material increase, the internal hole brackets become rarefied, and the oil content significantly increases, but the oil retention becomes lower, the friction coefficient becomes relatively high, the tensile strength and impact strength are significantly reduced.When the sintering temperature is 350℃, the impact strength is high; the strength of porous PI materials with different densities can be guaranteed by holding for 60 minutes. After optimizing the preparation process, the oil content of the material is 12.0%, and the friction coefficient is 0.092 after centrifuging oil for two hours.The impact strength is 105.9 kJ/m2 and the tensile strength is 74.2 MPa.

Keywords

• porous pi
• molding process
• oil-containing friction
• impact strength