Summarize this for me in 1 and half or more pages . And someone who understand HEA and MEA perfectly and is good at doing summary for this

A novel FeCrNiAlTi-based high entropy alloy strengthened by refined grains Danni Yang a , Yong Liu a, b, Haopeng Jiang a , Mingqing Liao a, Nan Qu a, Tianyi Han a, Zhonghong Lai a,c, Jingchuan Zhu a,b,, a School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, 150001, Heilongjiang, China b National Key Laboratory for Precision Hot Processing of Metals, Harbin Institute of Technology, Harbin, 150001, Heilongjiang, China " The Centre of Analysis Measurement, Harbin Institute of Technology, Harbin, 150001, Heilongjiang, China A R T IC L E I N FO A B S T R A C T 1. Introduction dendritic structure formed during solidification can influence the mechanical properties tremendously, and even following treat- For traditional alloys, to prevent the production of intermetallic ments are required [19,20]. So mechanical alloying combining with compounds, they are primarily based on one principal element, and hot-press sintering was proposed to prepare bulk HEAs [21,22]. just a slight amount of other alloying elements are added to control Grain refinement and homogeneous composition can be realized microstructures for better properties [1,2]. In 2004, a new type of by mechanical alloying, and hot-press sintering can consolidate multi-component alloys, termed as high entropy alloys (HEAs), was powders to form stable solid solution with high density. proposed by Yeh and Cantor et al. [3,4]. Importantly, the majority of Among plenty of HEAs systems reported so far, FeCrNi-based HEA systems form a stable body-centered cubic (BCC) and face- has aroused wide interests for an excellent combination of good centered cubic (FCC) solid solutions for their high entropy of mix- properties and low-cost [9,23-25]. Additionally Al and Ti were to ing [5,6]. In terms of properties, HEAs possess excellent mechanical improve the strength because the two elements can induce large properties [7-10], outstanding resistance of oxidation, wear and lattice strain and stress for their larger atomic radius among the corrosion [11-13], hence it has becoming a studying focus for great elements, and high Al content was to avoid brittle intermetallic of potential applications. FeAl while a slight addition of Ti is functioned as strengthening for To date, numerous methods have been applied to prepare HEAs, forming fine precipitates [22,26,27]. such as arc-melting [4], electro-deposition [14], laser cladding [15], Therefore, a novel FeCrNiAlTio.2 HEA was prepared by powder magnetron sputtering [16] and so on. Among these approaches, the metallurgy. The microstructure and mechanical properties were arc-melting is suitable to prepare the bulk metallic alloy [17,18]. explored systematically. The alloy reached quite high strength and However, for arc-melting, the composition segregation and plastic strain comparing with other reported FeCrNi-based HEAs. The strength mechanism was also analyzed. This new type of HEA get well along with the concept of cost-effective design, and the * Corresponding author. School of Materials Science and Engineering, Harbin study would further broaden the potential application for HEAs in Institute of Technology. Harbin 150001, Heilongjiang. China. high strength alloys. E-mail address: fgms@hit.edu.cn (J. Zhu). https://doi.org/10.1016/j.jallcom.2020.153729 0925-8388/@ 2020 Published by Elsevier B.V. 2. Experimental details The further characterizations of the sintered alloy were shown under Ar atmosphere, the ball-to-powder weight ratio of 10:1. The mean radius and volume fraction are 77.6nm,5% and 158.07nm,2% milling was break 5 min every 30min. After milling in Ar for 35h, respectively. 3 wt\% ethanol was injected into the vial as a process controlling The hardness of sintered FeCrNiAlTi i0.2 alloy is about 643HV0.5. agency (PCA) to prevent cold welding during milling, and the the curves of the true strain-stress and strain-hardening rate are powder was subsequently milled for 5h. When milling was shown in Fig. 4(a). The alloy possesses an outstanding mechanical finished, the milled powder was dried in a vacuum oven, and then properties, the compressive strength, yield strength and plastic the powder was allow to pass through a 75m sieve. Subsequently, strain are 2745MPa,1877MPa and 26.6% respectively. The strainthe milled powder was consolidated using VHPS at 1150C for 2h hardening rate curve in Fig. 4( a) demonstrates that the hardening with heating rate of 10C/min, and a constant uniaxial pressure of rate decreased linearly at the beginning stage, and then reduce the 50MPa was used during the sintering. The structure of the samples value slowly to 0 as the strain increases. Due to the independency of were characterized by X-ray diffractometry (XRD) with a CuK each mechanism, the yield strength is the result of comprehensive radiation. Scanning electron microscopy (SEM) with an energy effect, the yield strength can be ascribed to the frictional stress ( i ), dispersive spectrometer (EDS) was to observe morphology of bulk the grain boundary strengthening ( G), the dislocation strengthalloy. Transmission electron microscopy (TEM) was also used for ening ( Dis ), the solid solution strengthening ( SS) and the further structural characterization. Vickers micro-hardness was dispersion strengthening (D). The total strengthening of sintered tested, the applied load and dwell time were 0.5kgf and 10s HEA can be expressed as follows: respectively. The compressive strength was tested using an Instron5569 testing system at a strain rate of 1103s1. y=i+G+Dis+SS+D 3. Results and discussion where GB=KHPd1/2 (Hall-Petch relationship), Dis= After consolidated by VHPS, the relative density of bulk FeCr- MGb1/2 (Bailey-Hirsch [28]), SS= NiAlTi 00.2 reached to 97.42%. The XRD patterns of the samples are (i(kiCi)1/p)p( Gypen-Deruyttere formula [29]), and D= shown in Fig. 1. It was obvious that phase transformation occurred M0.4Gh1vln(2/b) (Orowan-Ashby equation [30,31]) respectively, deduring sintering for the appearance of splitting peaks on the tails are in the Appendix, and the calculated results of each pattern, the peak profile fitting corresponds with predominately a strengthening mechanism are listed in Table 1, it is clear that the BCC phase with lattice parameter of 2.8720A and a small friction of grain boundary strengthening and dislocation strengthening make B2 phase with lattice parameter of 2.890A A,and the phase fraction the main contributions in the alloy, besides dispersion strengthwas estimated to be 0.75 and 0.25 respectively. Besides, the crys- ening due to the existence of oxide inclusions also have strong talline size for the bulk HEA was calculated to be 174.1nm by strengthening effect on HEAs [31]. The calculated yield strength is deducting instrumental broadening. 2050MPa, a slightly higher than the experimental results of Fig. 2 illustrates the SEM micrograph of FeCrNiAlTi o22 HEA and 1877MPa, it is probably that full density was not reached and EDS results. The EDS mapping of the Fig. 2(b) Fig. 2(f) suggest that remained a small amount of porosity after sintering, which caused the dark regions correspond to Fe- Cr rich BCC phase while the light premature failure during deformation [32]. Fig. 4(b) shows the regions are Al-Ni rich B2 phase, and Ti tends to be in region of compressive strength and plastic strain of FeCrNi-based HEAs with AlNi rich [25]. The black spots are oxides for powder contami- similar components. Regardless of preparation methods, the FeCrnation during the milling and sintering, which can also be found NiAlTi 0.2 HEA possesses an excellent mechanical properties for from the XRD results. Fig. 2(g) shows the composition distributions achieving high plastic strain without sacrificing strength. The at three representative regions on the SEM image. The bar charts preparation method, phase structures and mechanical properties of indicate that the composition fluctuation keeps in a small range. are listed in Table of supplementary material. Fig. 3. TEM micrographs and corresponding SAED patterns of the sintered FeCrNiAlTi O0.2HEA alloy (a) Bright-field image; (b), (c) and (d), (e) SAED patterns of BCC and B2 phases along with [001] and [011] zone axis of the sintered alloy respectively. 4. Conclusions mechanical properties, the hardness is 643HV0.5, the yield The novel FeCrNiAlTi 00.2 HEA was firstly fabricated via powder strength, the compressive strength and plastic strain are 1877 MPa, metallurgy with relative density of 97.42%. The grain size of bulk 2745MPa and 26.6% respectively. The analysis of strengthening HEA is about 174.1nm, the alloy is composed of a major BCC suggests that grain refined strengthening and dislocation enriched in Fe-Cr and a minor B2 enriched in Ni-Al solid solution strengthening occupy a dominant position in the alloy, and the HEAs. oxides due to surface contamination triggered the dispersion strengthening is beneficial to high strength HEAs. Compared with other FeCrNi-based HEAs, the FeCrNiAlTi0.2 reaches a balance between strength and plastic strain. The relationship between composition and properties of the HEAs via powder metallurgy is required to consider in the future research