This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powde...This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powder metallurgy route to be used for industrial applications. The effect of concentration of TiB2 particles was studied by reinforcing TiB2 powder in different mass fractions (2wt%, 5wt%, 10wt%, and 20wt%) into pure Ti powder during the fabrication process. The MMCs were sintered at high temperatures under vacuum. The transmission electron microscopy (TEM) results revealed the formation of needle-shaped TiB whiskers, indicating that in situ reaction occurred during vacuum sintering of the powder compacts. All the composite samples had a high sintered density, and the hardness of the composites increased with an increase in the mass fraction of reinforcement. Mechanical and tribological properties such as flexural strength, impact, and wear properties were determined and found to be dependent on the mass fraction of the reinforcement. However, the mechanism for the in situ reaction needs further investigation by high-energy in situ X-ray diffraction techniques.展开更多
This paper characterises and evaluates Si_(3)N_(4)/Ti composites during thermal treatment using an in situ neutron diffraction technique.The composites were developed using a conventional press and sinter technique.Pu...This paper characterises and evaluates Si_(3)N_(4)/Ti composites during thermal treatment using an in situ neutron diffraction technique.The composites were developed using a conventional press and sinter technique.Pure titanium(Ti)was chosen as the matrix,and different concentrations of Si_(3)N_(4)were used as the reinforcement.The effects of sintering temperature and the concentration of Si_(3)N_(4)in the Ti matrix were investigated with respect to phase constituents.The Si_(3)N_(4)mass fraction in the Ti matrix was found to be the key parameter for the reaction.Because of its instability in Ti at higher temperatures,in situ reactions between the reinforcing particles and matrix led to the formation of intermetallic compounds,such as Ti_(5)Si_(3)and possibly Ti3Si,in the composites containing higher weight fractions of Si_(3)N_(4).展开更多
基金partially supported by the Titanium Technologies New Zealand (TiTeNZ) Programme funded by the Ministry of Business Innovation and Employment (MBIE), New Zealand
文摘This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powder metallurgy route to be used for industrial applications. The effect of concentration of TiB2 particles was studied by reinforcing TiB2 powder in different mass fractions (2wt%, 5wt%, 10wt%, and 20wt%) into pure Ti powder during the fabrication process. The MMCs were sintered at high temperatures under vacuum. The transmission electron microscopy (TEM) results revealed the formation of needle-shaped TiB whiskers, indicating that in situ reaction occurred during vacuum sintering of the powder compacts. All the composite samples had a high sintered density, and the hardness of the composites increased with an increase in the mass fraction of reinforcement. Mechanical and tribological properties such as flexural strength, impact, and wear properties were determined and found to be dependent on the mass fraction of the reinforcement. However, the mechanism for the in situ reaction needs further investigation by high-energy in situ X-ray diffraction techniques.
基金the Australian Institute of Nuclear Science and Engineering(AINSE)Ltd.for providing financial assistance(Award No.P7317)to enable work on WOMBAT to be conducted.Peng Cao acknowledges the support from the International Cooperation Programs of Guangzhou City(Grant number 20190710030)Guangdong Province,China(Grant No.108A050506010).
文摘This paper characterises and evaluates Si_(3)N_(4)/Ti composites during thermal treatment using an in situ neutron diffraction technique.The composites were developed using a conventional press and sinter technique.Pure titanium(Ti)was chosen as the matrix,and different concentrations of Si_(3)N_(4)were used as the reinforcement.The effects of sintering temperature and the concentration of Si_(3)N_(4)in the Ti matrix were investigated with respect to phase constituents.The Si_(3)N_(4)mass fraction in the Ti matrix was found to be the key parameter for the reaction.Because of its instability in Ti at higher temperatures,in situ reactions between the reinforcing particles and matrix led to the formation of intermetallic compounds,such as Ti_(5)Si_(3)and possibly Ti3Si,in the composites containing higher weight fractions of Si_(3)N_(4).
