Paper number 953

FRACTURE TOUGHNESS OF IN SITU SYNTHESISED TINP-ALNP/AL COMPOSITE

Chunxiang CUI¹ Yutian Shen¹ Fanbin Meng¹ Renjie WU²

1Hebei University of Technology, Tianjin 300130, CHINA
Tel: 022-26545801-438 Fax: 022-26536212.
E-mail: cxcui@hebut.edu.cn
2Key Lab. of State for MMCs, Shanghai Jiaotong University, Shanghai 200030, CHINA

Summary

The effect of particle size, particle volume fraction, and matrix microstructure on the fracture initiation toughness of in situ TiNp-AlN/Al composite was examined. The composites were Al matrix reinforced with 7.8 to 19.6 vol pct of TiN and AlN particles produced in situ by S-V-L reaction synthetics. The average particle diameters of TiN and AlN were 3.5 and 0.9 micrometer respectively, which were distributed in Al matrix dispersedly. The room-temperature plane-strain toughness measured using three point bending specimens ranged from 12.7 to 38.5 MPa. Toughness was adversely affected by increase in TiNp-AlNp volume fraction. Fractography revealed that these composite failed in a ductile manner, with voids initiating at the in situ reinforcing TiN and AlN particles. The experimentally measured plane-strain toughness properties of in situ TiNp-AlNp/Al composite agree with the Rice and Johnson model.

Keywords

reaction synthetics, toughness, plane-strain, in situ composite.