Mingzhen MA
,
Riping LIU
,
Hongli ZHAO
,
Yifa YU
材料科学技术（英文）
An in-situ TiCP/Al composite was prepared by a thermal explosion/quick pressure method (TE/QP). The effect of Al content on the reaction temperature as well as the reaction rate has been studied. Phase constituents and the microstructure of the composites and the particle size of the reinforcement were analysed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results have shown that TiCp/Al composite with 40～70 vol. pct TiC particle reinforcement and high relative density can be directly obtained by TE/QP. TiC is the only reaction product when Al content in Al-Ti-C system is no more than 60 vol. pct, but Al3Ti phase will also form when Al content is more than 60 vol. pct. Increasing Al content prolongs the initial reaction time, reduces the highest reaction temperature and the reaction rate, and decreases the size of TiC particles. In addition, the microstructure of TiCp/Al composite and the structure of interface between TiCp and Al are studied using SEM and transmission electron microscopy (TEM). The results show that the in-situ synthesized TiC particle has fcc cubic structure. The orientation between TiC particles and Al matrix can be described as ( )Al//( )TiC and [ ]Al//[011] TiC. Results of the mechanical property tests reveal that the ultimate strength (σ) and modulus (E) are 687~MPa and 142 GPa respectively when the Al content is 40 vol. pct. On contrary,δ elongation increases by 3.2% with increasing Al content.
关键词:
TiCp/Al composites
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null
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Mingzhen MA
,
Dayong CAI
,
Tianfu JING
材料科学技术（英文）
The microstructure of TiCp/2024 composite and the structure of interface between TiCp and Al are studied using SEM and TEM. The results show that the in-situ synthesized TiC particle has face-centered cubic structure (fcc). Meanwhile, particles are characterized as tiny and nearly globular. The orientation between TiC particles and Al matrix can be described as ((2) over bar(2) over bar0)(Al)//(02 (2) over bar)(Tic) and [(1) over bar 12](Al)//[011](TiC). Results of the mechanical property tests reveal that the ultimate strength (sigma (b)) and the yield strength (sigma (s)) of the composite are improved by 30% and 47% respectively, compared with the properties of 2024 matrix. In addition, the elongation (delta) value can still reach 4.3%. Thus TiCp/2024 composite has high comprehensive performance.
关键词:
Mingzhen MA
,
Dayong CAI
,
Tianhua WEI
材料科学技术（英文）
Direct reaction synthesis (DRS), based on the principle of self-propagating high-temperature synthesis (SHS), is a new method for preparing particulate metal matrix composites. TiCP/Al-4.5Cu-0.8Mg composites were fabricated by DRS. Particulate composites were fabricated with Ti carbide (TiC) particles, generally less than 1.0µm. The reacted, thermal extruded samples exhibit a homogeneous distribution of fine TiC particles in Al-4.5Cu-0.8Mg matrix. Mechanical property evaluation of the composites has revealed a very high tensile strength relative to the matrix alloy. Fractographic analysis indicates ductile failure.
关键词:
TiCP/Al-4.5Cu-0.8Mg composites
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null
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null
,
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