搅拌摩擦加工对耐高温SiC/Al复合材料组织及性能影响OA

To address the challenge of determining the process parameter sensitivity in friction stir processing(FSP)of SiC/Al composites,this study investigated the influence of travel speed on the microstructure and mechanical properties of a 25 wt.％SiC+1.5 wt.％TiO2+1 vol.％CNT/Al-1 wt.％Cu composite,aiming to provide a theoretical basis for optimizing the manufacturing process of brake discs.The base material was fabricated via powder metallurgy,and single-pass FSP was subsequently conducted using travel speeds of 50 mm/min(sample FSP50)and 100 mm/min(sample FSP100).Through microstructural characterization and tensile testing,a systematic analysis was conducted to evaluate the influence of travel speed on the microstructure and tensile properties at both room temperature and 300℃.The results indicate that FSP promotes a homogeneous distribution of SiC particles through the combined effects of shear and rheological flow;the thermomechanical coupling during FSP effectively refines the Al3Ti and Al2Cu particles,and the grain size decreases with increasing FSP travel speed.FSP100 exhibits an enhancement in room-temperature tensile strength,reaching 407 MPa,which is attributed to increased grain boundary strengthening and improved microstructural homogeneity;at 300℃,the composite strength decreases due to matrix softening and interfacial degradation.The fine SiC particle-Al interfaces introduced by FSP are more susceptible to debonding under high-temperature conditions.