Materials-structure-property correlation study of spark plasma sintered AlCuCrFeMnW x ( x = 0, 0.05, 0.1, 0.5) high-entr
- PDF / 995,587 Bytes
- 10 Pages / 584.957 x 782.986 pts Page_size
- 96 Downloads / 168 Views
FOCUS ISSUE
NANOCRYSTALLINE HIGH ENTROPY MATERIALS: PROCESSING CHALLENGES AND PROPERTIES
Materials-structure-property correlation study of spark plasma sintered AlCuCrFeMnWx (x = 0, 0.05, 0.1, 0.5) high-entropy alloys Devesh Kumar1,2, Vishnu K. Sharma1, Y.V.S.S. Prasad1, Vinod Kumar3,a) 1
Department of Metallurgical and Materials Engineering, Malaviya National Institute of Technology (MNIT) Jaipur, 302017, India Department of Mechanical Engineering Jaipur Engineering College and Research Centre (JECRC), Jaipur 302017, India 3 Discipline of Metallurgy and Materials Science, Indian Institute of Technology (IIT) Indore, 453552, India a) Address all correspondence to this author. e-mail: [email protected] 2
Received: 4 July 2018; accepted: 2 January 2019
A novel series of nanocrystalline AlCuCrFeMnWx (x = 0, 0.05, 0.1, 0.5) high-entropy alloys (HEAs) were synthesized by mechanical alloying followed by spark plasma sintering. The phase evolution of the current HEAs was studied using X-ray diffraction (XRD), transmission electron microscopy, and selected area electron diffraction. The XRD of the AlCuCrFeMn sintered HEA shows evolution of ordered B2 phase (AlFe type), sigma phase (Cr rich), and FeMn phase. AlCuCrFeMnWx (x = 0.05, 0.1, 0.5 mol) shows formation of ordered B2 phases, sigma phases, FeMn phases, and BCC phases. Micro-hardness of the AlCuCrFeMnWx samples was measured by Vickers microindentation and the maximum value observed is 780 ± 12 HV. As the tungsten content increases, the fracture strength under compression increases from 1010 to 1510 MPa. Thermodynamic parameters of present alloys confirm the crystalline phase formation, and finally structure–property relationship was proposed by conventional strengthening mechanisms.
Introduction
strength. HEA research often adds elements directly to the
High-entropy alloys (HEAs) are a comparatively new breed of materials of general interest in the metallurgical research community in recent years. They are classified by their unconventional composition, as they do not surround a single main component, but instead contain more than one elements [1, 2]. Based on the indication already existing in the literature to date, it seems to be that the core effects of HEAs related with entropy stabilization, lattice distortion, and sluggish diffusion may not be as prominent as initially proposed. Few examples of HEAs are considered to be entropy-stable solid solutions: both experiments and theories show that adding more components to the alloy can lead to intermetallic formation or phase separation. There are some recent thoughts about alternative naming conventions, like “compositionally complex alloys” or “complex concentrated alloys’”. Still, the author argues that since the terminology of “HEA” is so ingrained in the discourse, changes in the naming convention can only lead to confusion [3, 4, 5]. In general, good corrosion resistance, toughness, and oxidation resistance will be required alongside
resulting mechanical properties [6, 7, 8]. Similarly, several
ª Materia
Data Loading...
