Mechanical performance and fracture behavior of Fe 41 Co 7 Cr 15 Mo 14 Y 2 C 15 B 6 bulk metallic glass
- PDF / 270,219 Bytes
- 6 Pages / 585 x 783 pts Page_size
- 45 Downloads / 180 Views
J. Shena) School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, People’s Republic of China
D.L. Zhang Department of Materials and Process Engineering, The University of Waikato, Hamilton, New Zealand
H.B. Fan and J.F. Sun School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, People’s Republic of China (Received 7 June 2006; accepted 18 September 2006)
The mechanical properties of a new Fe41Co7Cr15Mo14Y2C15B6 bulk glassy alloy were studied by impact bending, compression, and hardness tests carried out at room temperature. The compressive fracture strength, elastic strain to fracture, Young’s modulus and Vickers hardness were measured to be 3.5 GPa, 1.5%, 265 GPa, and 1253 kg mm−2, respectively. The fracture mode of the glassy alloy under uniaxial compression is different from those of other bulk metallic glasses in that this fracture mode causes the samples to be broken, in an exploding manner, into a large number of micrometer-scale pieces. The fracture mechanisms of this bulk glassy alloy under bending and uniaxial compression are discussed based on the observation of the fracture surfaces. Vickers indentation tests indicate that the structure of the glassy ingot may be inhomogeneous. I. INTRODUCTION 1–3
Recently, the mechanical behavior of Cu-based, Zrbased,4–6 and Pd-based7,8 bulk metallic glasses (BMGs) has been investigated extensively. However, little research has been reported on the mechanical properties of Fe-based BMGs, mainly because only recently Febased BMGs with high glass-forming ability (GFA)9–13 have been developed. Understanding their mechanical behavior is becoming increasingly important because the high strength and potential low cost of Fe-based BMGs make them attractive for use as advanced engineering materials. The fracture behavior of BMGs can be classified into two categories based on previous studies: ductile fracture, which has been observed, for example, in ZrCu-based,14 Pt-based,15 and Cu-based16 BMGs; and brittle fracture, which has been observed in Fe-based,12,13 Mg-based,17 and Y-based18 BMGs. In this work, the mechanical behavior of a new Fe-based BMG possessing the highest
a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/JMR.2007.0038 358 J. Mater. Res., Vol. 22, No. 2, Feb 2007 http://journals.cambridge.org Downloaded: 13 Apr 2015
GFA among Fe-based BMGs discovered so far has been studied to gain insight into the fracture mechanisms of this Fe-based BMG alloy. II. EXPERIMENTAL PROCEDURE
BMG rods with a composition of Fe 41 Co 7 Cr 15 Mo14Y2C15B6were obtained by arc melting a mixture of pure elements Fe, Co, Cr, Mo, Y, C, and FeB pieces in a Ti-gettered argon atmosphere and drop casting the liquid alloy, using its own gravity, into a copper mold 3 mm in diameter. The samples for compression tests had dimensions of 6-mm length and 3-mm diameter and were sliced from the as-cast rods. Both ends of the cylindrical samples were ground and polished to make them flat and
Data Loading...
