Improvement of particles distribution of in-situ 5 vol% TiB2 particulates reinforced Al-4.5Cu alloy matrix composites with ultrasonic vibration treatment

• Published in: Journal of alloys and compounds 2017-01, Vol.692, p.1-9
• Main Authors: Gao, Qi, Wu, Shusen, Lü, Shulin, Xiong, Xinchen, Du, Rui, An, Ping
• Format: Article
• Language: English
• Subjects: Acoustic streaming; Agglomeration; Agglomerations; Aluminum base alloys; Aluminum matrix composites; Cavitation; Diffraction; Fiber reinforced composites; Grain boundaries; Intermetallic compounds; Particulate composites; Particulates; TiB2; Titanium aluminides; Titanium diboride; Ultimate tensile strength; Ultrasonic technology; Ultrasonic vibration
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2016.09.013

Ultrasonic vibration treatment is successfully applied in preparation of in-situ 5 vol% TiB2 particulates reinforced Al-4.5Cu alloy matrix composites with salt-metal reaction route. Formation of TiB2 phase is confirmed by X-ray diffraction analysis, and intermediate phases such as Al3Ti are not detected. Agglomerations of particles in the melt are effectively eliminated by the cavitation and acoustic streaming affects in the melt with ultrasonic vibration. TiB2 particles are uniformly distributed throughout the bulk melt after treated by ultrasonic vibration for 240 s. The tiny agglomerations formed by TiB2 particles smaller than 100 nm are also broken by ultrasonic vibration. Some TiB2 particles smaller than 400 nm are observed to dispersed near grain boundary in the matrix after solidification. The optimal improvements of yield strength and ultimate tensile strength are 114% and 50%, respectively, when composite treated by ultrasonic vibration for 240 s. [Display omitted] •Large agglomerations were eliminated by short time ultrasonic vibration treatment.•Small agglomerations were eliminated by long time ultrasonic vibration treatment.•Tiny TiB2 agglomerations formed by particles 10–100 nm in size are broken.