Roy, D and Mitra, R and Ojo, O A and Lojkowski, W and Manna, Indranil (2011) Microstructural Evolution and Mechanical Properties of Nanointermetallic Phase Dispersed Al(65)Cu(20)Ti(15) Amorphous Matrix Composite Synthesized by Mechanical Alloying and Hot Isostatic Pressing. Metallurgical and Materials Transactions A-Physical Metallurg and Materials Science, 42A (8). pp. 2498-2508. ISSN 1073-5623

PDF - Published Version Restricted to Registered users only Download (682Kb) | Request a copy

Abstract

The structure and mechanical properties of nanocrystalline intermetallic phase dispersed amorphous matrix composite prepared by hot isostatic pressing (HIP) of mechanically alloyed Al(65)Cu(20)Ti(15) amorphous powder in the temperature range 573 K to 873 K (300 A degrees C to 600 A degrees C) with 1.2 GPa pressure were studied. Phase identification by X-ray diffraction (XRD) and microstructural investigation by transmission electron microscopy confirmed that sintering in this temperature range led to partial crystallization of the amorphous powder. The microstructures of the consolidated composites were found to have nanocrystalline intermetallic precipitates of Al(5)CuTi(2), Al(3)Ti, AlCu, Al(2)Cu, and Al(4)Cu(9) dispersed in amorphous matrix. An optimum combination of density (3.73 Mg/m(3)), hardness (8.96 GPa), compressive strength (1650 MPa), shear strength (850 MPa), and Young's modulus (182 GPa) were obtained in the composite hot isostatically pressed (''hipped'') at 773 K (500 A degrees C). Furthermore, these results were compared with those from earlier studies based on conventional sintering (CCS), high pressure sintering (HPS), and pulse plasma sintering (PPS). HIP appears to be the most preferred process for achieving an optimum combination of density and mechanical properties in amorphous-nanocrystalline intermetallic composites at temperatures a parts per thousand currency sign773 K (500 A degrees C), while HPS is most suited for bulk amorphous alloys. Both density and volume fraction of intermetallic dispersoids were found to influence the mechanical properties of the composites.

Item Type:	Article
Subjects:	Microstructure and Characterization
Divisions:	UNSPECIFIED
Depositing User:	Bidhan Chaudhuri
Date Deposited:	17 Jan 2012 11:16
Last Modified:	29 Mar 2012 12:54
URI:	http://cgcri.csircentral.net/id/eprint/330

Actions (login required)

View Item