Peng Jin
材料科学技术（英）
The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 vol.% SiCp/2009Al composites fabricated at different hot pressing temperatures were investigated. After hot extrusion, the relative density of the composites increased, the SiC particle distribution became more uniform, and the SiC particles tended to align along the extrusion direction. Furthermore, the interface bonding was improved after hot extrusion; however, the extrusion exerted no obvious effect on the interfacial reaction products formed during sintering process. Tensile tests indicated that the mechanical properties of the composites were improved significantly after extrusion. Fractography revealed that the fracture mechanism of the extruded composites fabricated at the hot pressing temperatures below 540°C was mainly the interfacial debonding. For the extruded composites fabricated at 560-600°C, the fracture was the matrix ductile fracture and the SiC particle fracture. When the composites were hot pressed at or above 620°C, after extrusion, the fracture mechanism of the composites was the matrix ductile fracture, the interface cracking and the SiC particle fracture.
关键词:
Aluminum matrix composite
Peng Jin
材料科学技术（英）
The effects of hot extrusion on the interfacial microstructures and tensile properties of 15 vol.% SiCp/2009Al composites fabricated at different hot pressing temperatures were investigated. After hot extrusion, the relative density of the composites increased, the SiC particle distribution became more uniform, and the SiC particles tended to align along the extrusion direction. Furthermore, the interface bonding was improved after hot extrusion; however, the extrusion exerted no obvious effect on the interfacial reaction products formed during sintering process. Tensile tests indicated that the mechanical properties of the composites were improved significantly after extrusion. Fractography revealed that the fracture mechanism of the extruded composites fabricated at the hot pressing temperatures below 540°C was mainly the interfacial debonding. For the extruded composites fabricated at 560-600°C, the fracture was the matrix ductile fracture and the SiC particle fracture. When the composites were hot pressed at or above 620°C, after extrusion, the fracture mechanism of the composites was the matrix ductile fracture, the interface cracking and the SiC particle fracture.
关键词:
Aluminum matrix composite
Wei GUO
,
Jitai NIU
,
Jinfan ZHAI
,
Changli WANG
,
Jie YU
,
Guangtao ZHOU
材料科学技术（英）
Through the vacuum diffusion bonding for SiCp/ZL101 aluminum matrix composite, the influence of bonding parameters on the joint properties was reported, with the aim to obtain optimal bonding parameters. The microstructure of joints was analyzed by means of optical microscope and scanning electron microscope in order to study the relationship between the macro-properties of joints and the microstructures. It was found that diffusion bonding could be used for bonding aluminum matrix composites successfully. Meanwhile, the properties of the matrix and the joint were all affected by some defects such as the reinforcement aggregation in aluminum matrix composites made by stirring casting.
关键词:
Aluminum matrix composite
,
null
,
null
,
null
Jitai NIU
,
Wei GUO
,
Qingchang MENG
,
Xinmei ZHANG
,
Xingqiu LIU
,
Guangtao ZHOU
材料科学技术（英）
The liquid-phase-impacting (LPI) diffusion welding mechanism and microstructure of welded joint of aluminum matrix composite SiCp/101A have been studied. It shows that by LPI diffusion welding, the interface state between SiC particle and matrix is prominent, the harmful microstructure or brittle phase can be restrained from the welded joint. Moreover, the density of dislocation in the matrix near the interface and in the matrix are all so higher than that of parent composite, the dislocation entwists each other intensively resulted in welding the composite successfully.
关键词:
Aluminum matrix composite
,
null
,
null
Wei GUO
,
Qingchang MENG
,
Jitai NIU
,
Xinmei ZHANG
材料科学技术（英）
In this paper, a new method for welding SiCp/101A was put forward. It is LPI (liquid-phase-impacting) diffusion welding. Through LPI diffusion welding SiCp/101A aluminum, the effect of welding parameters on the welded joint property was investigated, and the optimal welding parameters were brought forward at the same time. The microstructure of joint was analyzed by means of optical-microscope, scanning electron microscope in order to study the relationship between the macro-properties of joint and the microstructure. The results show that LPI diffusion welding could be used for welding aluminum matrix composites SiCp/101A successfully.
关键词:
Aluminum matrix composite
,
null
,
null
Min ZHAO
材料科学技术（英）
TiB2P/Al composite was successfully fabricated by squeeze casting technology. Its mechanical and tribological properties were evaluated. The elimination of Ti-Al intermetallic compound was confirmed by X-ray diffraction (XRD) studies. At 45% volume fraction, the bending strength at ambient temperature was 934 MPa. And the fracture modes included ductile failure of Al matrix and brittle fracture of TiB2 particles. In dry sliding wear mode, severe plastic deformation and adhesive wear were found on the worn surfaces of the SiCP/Al composite. But no obvious characteristics of adhesion or abrasion wear were observed on that of the TiB2P/Al composites. At the steady stage, the friction coefficient of the SiC2P/Al composite was about 0.6. While that of TiB 2P/Al composite was only about 0.16~0.17.
关键词:
TiB2
,
null
,
null
,
null
Qiang ZHANG
,
Gaohui WU
,
Dongli SUN
,
Bofeng LUAN
材料科学技术（英）
The AlN particle reinforced aluminum matrix composites with 50% volume fraction were fabricated by squeeze-casting technology. The thermal expansion behavior and its response to thermal cycling were studied between 20℃ and 400℃. Compared with four theoretical models, the measured CTEs of the composite lie within the elastic bounds derived by Schapery's analysis. Schapery's model and Kerner's model agree well with the CTEs of the composites at lower temperature and elevated temperature, respectively. Strain hysteresis was observed between heating and cooling curves during cycling. This was attributed primarily to the anelastic behavior of the matrix induced by matrix residual stresses.
关键词:
AlN
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null
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null
,
null
