#
Effect of Minor Ce Substitution for Pr on the Glass Formability and Magnetocaloric Effect of a Fe_{88}Zr_{4}Pr_{4}B_{4} Metallic Glass

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## Abstract

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_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}metallic glass (MG) was successfully prepared by minor Ce substitution for Pr, and compared with Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG in terms of glass forming ability (GFA), magnetic and magnetocaloric properties. The GFA, T

_{c}and the maximum magnetic entropy change (−ΔS

_{m}

^{peak}) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG were found to decrease slightly. At the same time, the possible interaction mechanism of minor Ce replacing Pr was also explained. The critical exponents (β, γ and n) obtained by the Kouvel–Fisher method indicate that Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG near T

_{c}exhibits typical magnetocaloric behavior of fully amorphous alloys. The considerable maximum magnetic entropy change (−ΔS

_{m}

^{peak}= 3.84 J/(kg × K) under 5 T) near its Curie temperature (T

_{c}= 314 K) as well as RCP (~ 646.3 J/kg under 5 T) make the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG a better candidate as a component of the amorphous hybrids that exhibit table-shape magnetic entropy change profiles within the operation temperature interval of a magnetic refrigerator.

## 1. Introduction

_{m}) under a certain magnetic field. As such, early research focused on the MCE of first-order magnetic phase transition (FOMPT) materials that exhibit a sharp −ΔS

_{m}profile with rather high maximum −ΔS

_{m}(−ΔS

_{m}

^{peak}) [7,8,9]. However, the narrow working temperature intervals of these FOMPT materials make them difficult to match the requirements of magnetic refrigerants working in an Ericsson cycle; that is, a fattened −ΔS

_{m}curve over the range of operating temperatures in a magnetic refrigerator [10]. In addition, the FOMPT materials inevitably show some disadvantages such as high magnetic and thermal hysteresis [11]. In contrast, amorphous magnetocaloric alloys that experience a second-order magnetic phase transition (SOMPT) exhibit several characteristics superior to the FOMPT materials, such as low energy loss induced by their negligible coercivity and high electric resistance, broadened −ΔS

_{m}curve and tunable −ΔS

_{m}peak temperature that make them easily composed to achieve the fattened −ΔS

_{m}curve [12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31]. Unfortunately, although rare earth (RE)-based metallic glasses (MGs) exhibit rather high glass formability (GFA), excellent −ΔS

_{m}

^{peak}at low temperature and ultrahigh refrigeration capacity (RC), their formability and −ΔS

_{m}

^{peak}get worse when their Curie temperature (T

_{c}) increases to or above the ambient temperature [12,13,14,15,16,17,18]. Thus, RE-based amorphous magnetocaloric alloys are more likely to be applied in low temperature refrigeration instead of room temperature (RT) refrigeration. The Fe-based amorphous magnetocaloric alloys exhibit good glass formability when their T

_{c}is near the ambient temperature, but their −ΔS

_{m}

^{peak}is usually very low [19,20,21,22,23]. For example, Fe-Zr-B MGs with T

_{c}ranging from the cold end (T

_{Cold}) to the hot end (T

_{Hot}) of domestic cooling equipment can be easily fabricated, but their −ΔS

_{m}

^{peak}under 5 T is less than 3.34 J/(kg × K) [21,22,23], which is far from enough for them to be utilized as cooling agents in domestic cooling appliances. More recently, by microalloying the Fe-Zr-B MGs with other transition metals or RE metals, we successfully adjusted the T

_{c}and improved the −ΔS

_{m}

^{peak}of the Fe-Zr-B MGs [24,25,26,27,28,29,30,31]. For instance, the −ΔS

_{m}

^{peak}under 5 T reaches 3.55 J/(kg × K) at 336 K in the Fe

_{85}Co

_{3}Zr

_{5}B

_{4}Nb

_{3}amorphous ribbon [24] and at 333 K in the Fe

_{85}Zr

_{8}B

_{4}Sm

_{3}amorphous ribbon [25]; it reaches 4.0 J/(kg × K) at 323 K in the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}amorphous ribbon [26] and 4.10 J/(kg × K) at 335 K in the amorphous Fe

_{88}Zr

_{4}Nd

_{4}B

_{4}ribbon [27].

_{Hot}of a domestic refrigerator. It is known that the high −ΔS

_{m}

^{peak}at temperatures higher than T

_{Cold}but lower than T

_{Hot}is also required for the construction of fattened −ΔS

_{m}curves suitable for the Ericsson refrigeration cycle. Thus, it is necessary to develop a new type of metallic glass with excellent MCE at RT. As such, it is critical to decrease the −ΔS

_{m}peak temperature of the iron-based MGs without dramatically deteriorating their −ΔS

_{m}

^{peak}. In the present work, according to our preliminary results on the effect of Ce substitution on the T

_{c}and −ΔS

_{m}

^{peak}of the Fe-Zr-B amorphous alloys [32], we add minor Ce to replace the Pr element in the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}amorphous alloy for the purpose of obtaining good magnetocaloric properties at a temperature slightly lower than the T

_{Hot}of a domestic refrigerator. The mechanism for the influence of minor Ce substitution on the magnetic as well as magnetocaloric properties of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}metallic glass was also investigated. The research results provide a feasible path for the Fe-Zr-B-RE amorphous alloy to reduce T

_{c}and avoid significant deterioration of magnetocaloric properties while reducing costs.

## 2. Materials and Methods

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ingot was manufactured by arc-melting the high purity raw materials more than five times to ensure uniformity of composition [33]. Ribbons were fabricated by spraying the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}melt from a quartz tube to the surface of a copper roller rotating at a linear velocity of 55 m/s. The whole sample preparation process is protected by a high purity Ar atmosphere. The cross-sectional morphology of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as-spun ribbon was characterized through a Hitachi tungsten filament scanning electron microscope (SEM, model SU-1500). The ~40-μm-thickness as-spun ribbons were selected for structural analysis by X-ray diffraction (XRD) using a Cu K

_{α}radiation with a scanning speed of 1 °/min on a PANnalytical spectrometer. Under program-controlled temperature conditions, the glass transition behavior, melting and crystallization of Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbons were distinguished by measuring the power difference between the sample and the reference material as a function of temperature (i.e., the thermal effect information related to heat absorption and release). Hence, the thermodynamic parameters, including glass transition temperature (T

_{g}), initial crystallization temperature (T

_{x}) and liquidus temperature (T

_{l}), were derived from the differential scanning calorimetry (DSC) curve measured by a NETZSCH DSC-404 C calorimeter at a heating speed of 20 K/min to evaluate the formability of the MG ribbon. The temperature dependence of the heat capacity (C

_{p}(T)) curve of the glassy sample was measured by a Perkin-Elmer DIAMOND calorimeter. The magnetic measurements of the amorphous ribbons, including magnetization vs. temperature (M-T) curve, isothermal magnetization (M-H) curve and hysteresis loop, were performed on the vibrating sample magnetometer (VSM) module of a physical property measurement system (PPMS, model 6000, Quantum Design) after applying an oscillating magnetic field to a fully amorphous ribbon to eliminate residual magnetism. The sample for magnetic measurement was prepared by sticking several ribbons together using non-magnetic cement. To minimize the impact of demagnetization, the magnetic field is applied parallel to the length of the sample.

## 3. Results and Discussion

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as-spun ribbon is amorphous according to its XRD pattern shown in Figure 1. The cross-sectional morphology (the upper left inset of Figure 1a) and the prepared samples (the upper right inset of Figure 1a) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as-spun ribbon, indicate a thickness of ~40 μm and a width of ~2 mm. The glassy characteristic of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbon is also illustrated by the upward glass transition hump before the downward crystallization peak on its DSC trace, as shown in Figure 1b. The onset of T

_{g}and T

_{x}of the amorphous ribbon determined from its DSC trace is ~795 K and ~856 K, respectively. The T

_{l}of Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}alloy obtained from its melting curve, which is illustrated in the inset of Figure 1b, is determined to be ~1545 K. Therefore, we can assess the GFA of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous sample by calculating the reduced glass transition temperature (T

_{rg}= T

_{g}/T

_{l}= 0.515) [34] as well as the parameter γ (= T

_{x}/(T

_{g}+ T

_{l}) = 0.366) [35]. The T

_{rg}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG sample is slightly higher than that of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG [26], while the γ parameter is slightly decreased by the Ce substitution. Therefore, it seems that the Ce addition does not obviously change the glass formability of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}metallic glass. On the other hand, although the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as well as Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MGs do not show T

_{rg}and γ values comparable to the bulk metallic glasses, their T

_{rg}and γ values are still larger than most other Fe-Zr-B MGs [21,22,23], indicating that the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}and Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}alloys can be easily prepared into MG ribbon.

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}sample was measured after a zero-field-cooling process from RT. Figure 2a depicts the M-T curve under 0.03 T of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}glassy sample. The ferromagnetic materials exhibit strong magnetism when magnetized. However, as the temperature increases, the intensification of thermal motion will affect the ordered arrangement of magnetic moments of the magnetic domain. When the temperature reaches enough to disrupt the orderly arrangement of magnetic moments of the magnetic domain, the magnetic domain is disrupted, the average magnetic moment becomes zero and the magnetism of ferromagnetic materials disappears and becomes paramagnetic. As seen in the (dM/dT)-T plots of the sample in the inset, T

_{c}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG is thus determined at the minimum value of the dM/dT to be 314 K, which is about 9 K lower than that of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG [26]. The decreased T

_{c}caused by the replacement of Ce for Pr may be closely related to the antiferromagnetic coupling of the Ce atom with the Fe atom [32]. The hysteresis loops of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG ribbon, as displayed in Figure 2b, suggest that the MG is paramagnetism at 380 K and soft magnetism at 200 K. The Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG exhibits excellent soft magnetic properties with almost zero hysteresis and high magnetic susceptibility at 200 K, both of which are typical characteristics of fully amorphous alloys and are essential for magnetocaloric materials. The saturation magnetization (M

_{s}) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}alloy (~129 Am

^{2}/kg at 200 K) is slightly lower than that of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG (~137 Am

^{2}/kg at 200 K [26]), indicating that the magnetocaloric properties of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG may be not as high as Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG because both the M

_{s}and the −ΔS

_{m}of the amorphous alloys are primarily determined by the ordering of their magnetic moments.

_{m}(−ΔS

_{m}-T curve) can be derived from the M-H curves measured at various temperatures. Figure 3a displays the M-H curves of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG from 200 K to 380 K under 5 T. On the basis of these M-H curves, the M

^{2}-H/M plots, namely the Arrott plots of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG, can be established accordingly, as illustrated in Figure 3b. The Arrott plots (M

^{2}-H/M) at each temperature show a positive slope and are almost parallel to each other from 200 K to 380 K, both of which indicate the typical feature of the materials experiencing a SOMPT according to the Banerjee criterion [36]. The second-order magnetic transition allows the alloy to undergo a continuous phase transition in a broad temperature range and hence leads to a better overall cooling capacity. The −ΔS

_{m}-T curves under various external magnetic fields of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG obtained from its M-H curves are depicted in Figure 4a. The −ΔS

_{m}

^{peak}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbon reaches 1.15 J/(kg × K) under 1 T, 1.57 J/(kg × K) under 1.5 T, 1.94 J/(kg × K) under 2 T, 2.63 J/(kg × K) under 3 T, 3.26 J/(kg × K) under 4 T and 3.84 J/(kg × K) under 5 T at 312.5 K. The −ΔS

_{m}

^{peak}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbon is marginally lower than that of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG [26], probably because of the lower magnetic moment of the Ce atom than the Pr atom due to there being only one up-paired electron in the 4f shell of Ce atom. The minor Ce atom substitution for Pr atom reduces the total magnetic moment of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG, which is confirmed by the effective magnetic moment (μ

_{eff}). As shown in Figure 4b, the temperature dependence of H/M of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}and Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbons were obtained from their M-T curves. According to the Curie–Weiss law [37], the slopes of the lines above their T

_{c}are correlated to the μ

_{eff}, and, thus, the μ

_{eff}of the two MGs are calculated to be about 8.89 μ

_{B}for Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}and 7.74 μ

_{B}for Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}. Apparently, the μ

_{eff}of the alloy is reduced with the addition of the Ce atom, resulting in a decrease in −ΔS

_{m}

^{peak}.

_{m}

^{peak}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}ribbon is not as high as that of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG, it is still higher than the −ΔS

_{m}

^{peak}near 310 K of other amorphous alloys and even high entropy alloys (HEA) reported in the literature [25,26,38,39,40,41]. For example, its −ΔS

_{m}

^{peak}under 5 T is about 234% higher than that of the Al

_{20}Mn

_{20}Fe

_{20}Co

_{15.5}Cr

_{24.5}HEA (1.15 J/(kg × K) at 314 K [38]), 193% higher than that of the Mn

_{20}Al

_{20}Co

_{14}Fe

_{23}Cr

_{23}HEA (1.31 J/(kg × K) at 310 K [39]), 22.3% higher than that of the Fe

_{87}Zr

_{7}B

_{4}Dy

_{2}MG (3.14 J/(kg × K) at 308 K [40]), 17.4% higher than that of the Fe

_{87}Zr

_{8}B

_{4}Sm

_{1}MG (3.27 J/(kg × K) at 308 K [25]), 5.5% higher than that of the Fe

_{86}La

_{7}B

_{5}Ce

_{2}MG (3.64 J/(kg × K) at 313 K [41]) and 6.67% larger than that of the Fe

_{88}Zr

_{6}Pr

_{2}B

_{4}MG (3.6 J/(kg × K) at 306 K [26]). Figure 4c displays the −ΔS

_{m}-T curves of several iron-based MGs under 5 T. The Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG ribbon shows a rather high −ΔS

_{m}

^{peak}near 310 K. On the other hand, the relative cooling power (RCP = −ΔS

_{m}

^{peak}× ΔT

_{FWHM}, where ΔT

_{FWHM}is the full width at the half of −ΔS

_{m}

^{peak}[42]) of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{3}Ce

_{1}MG, can be calculated as 164.7 J/kg under 1.5 T and 646.3 J/kg under 5 T according to the −ΔS

_{m}-T curve, both of which are similar to the values of amorphous alloys and much higher than those of the first-order magnetic transition alloys or compounds [26,41,43,44]. Since the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG experiences an SOMPT, it exhibits large value of magnetic entropy changes over a wide temperature range, which may be caused by the coupling interaction between RE-RE and RE-TM. Therefore, it can be predicted that Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG has a good magnetocaloric effect over a large temperature range.

_{m})-ln(H) plots at each temperature, we can achieve their slopes (defined as n) by linearly fitting and thus, observe the magnetocaloric behaviors of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG in more detail. Figure 5a represents the temperature dependence of n (n-T curve) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon. Similar to other amorphous alloys [21,22,24,26,27,40], the n of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG is close to 1 at temperatures well below its T

_{c}, and smoothly drops to the minimum value near its T

_{c}, then dramatically increases with the increasing temperature and approaches 2 at temperatures much higher than its T

_{c}. The minimum n value of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG ribbon, which appears at 312.5 K and is shown in the inset of Figure 5a, is ~0.747 and is close to the predicted value of amorphous alloys proposed by V. Franco et al. based on the Arrott–Nokes equation [45]. Both the n-T curve and the minimum n value of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG indicate typical magnetocaloric behaviors similar to those of fully MGs.

_{c}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG can also be explored by its critical exponents; that is, n(T

_{c}) = 1 + (β − 1)/(β + γ) [45]. Wherein, β and γ are the exponents related to spontaneous magnetization (M

_{st}) and initial susceptibility (χ

_{0}), respectively, which can be described as follows [46]:

_{st}(T) = M

_{0}(−ε)

^{β}, ε < 0, T < T

_{c}

_{0}(T)

^{−1}= (H

_{0}/M

_{0})ε

^{γ}, ε > 0, T > T

_{c}

_{0}and H

_{0}are the critical amplitudes, ε = (T − T

_{c})/T

_{c}is the reduced temperature. Based on Equations (1) and (2), Kouvel and Fisher proposed a method to determine the critical exponents β and γ with high accuracy, namely the Kouvel–Fisher (KF) method [47]. Equations (1) and (2) can be rewritten as:

_{st}(T)·(dM

_{st}(T)/dT)

^{−1}= (T − T

_{c})/β

_{0}(T)

^{−1}·(dχ

_{0}(T)

^{−1}/dT)

^{−1}= (T − T

_{c})/γ

^{2.5}-(H/M)

^{0.75}) at various temperatures of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG and obtained the temperature dependence of M

_{st}and χ

_{0}

^{−1}from the intersections of the linear extrapolation of high field regions with M

^{2.5}and (H/M)

^{0.75}axes, respectively. Figure 5b shows the temperature dependence of M

_{st}(T)·(dM

_{st}(T)/dT)

^{−1}and χ

_{0}(T)

^{−1}·(dχ

_{0}(T)

^{−1}/dT)

^{−1}of the ribbon. The critical exponents β and γ can be determined to be 0.438 and 1.384 from the slope of the linear fitting of the two plots. The values of β and γ are close to those of other iron-based MGs [45,48]. Therefore, the n value near T

_{c}based on the KF method is calculated to be 0.692, which is slightly lower than the n value based on the Arrott–Nokes equation, but still higher than the theoretical value of the mean field model [45,49,50]. The reason for this may be related to the unique short-range ordered microstructure of MGs.

_{c}, that is:

_{c}of 314 K for the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG, the M-H curve at 315 K was selected to construct the ln(M) vs. ln(H) plot, as shown in Figure 5c. The linear fitting is rather accurate, with a regression coefficient (Adj. R-Square) of up to 0.9999. The value of the exponent δ is derived from the slope of the linear fitting to be 4.093 ± 0.003, which is close to the result based on the Widom scaling relation. Therefore, according to Equation (5), we can obtain that RC is roughly proportional to H

^{1.24}. The ln(RCP)-ln(H) plot of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG constructed from its RCP under different fields is illustrated in Figure 5d. The plot also fits well linearly and the slope is determined to be 1.130 ± 0.005. Clearly, the N value obtained from the ln(RCP)-ln(H) plot is slightly lower than that obtained from the KF method and the modified Equation (6), but these values are around the range of iron-based MGs. The deviation of n and N are supposed to be due to the error in obtaining M

_{st}and χ

_{0}

^{−1}from the modified Arrott plots.

_{m}of the SOMPT materials has been proposed by V. Franco et al. [53]. The −ΔS

_{m}-T curves under all magnetic fields are normalized with their respective −ΔS

_{m}

^{peak}; that is, $\u2206{S}^{\u2019}\left(T,{H}_{max}\right)=\u2206{S}_{m}\left(T,{H}_{max}\right)/\u2206{S}_{m}^{peak}\left(T,{H}_{max}\right)$. The temperature axis is divided into upper and lower parts with T

_{c}as the boundary, and rescaled in different ways, as follows:

_{r}

_{1}and T

_{r}

_{2}are the starting and ending temperatures corresponding to ΔT

_{FWHM}under different magnetic fields, respectively. Figure 6a shows ΔS

_{m}/ΔS

_{m}

^{peak}-θ curves under different magnetic fields of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG. We can find that the normalized ΔS

_{m}curves under each magnetic field can collapse onto the same universal curve. This uniformity indicates the typically magnetocaloric behavior of the SOMPT Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG.

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG in a more direct way, we calculated the adiabatic temperature rise (ΔT

_{ad}) of the amorphous ribbon, as follows:

_{ad}(ΔT

_{ad}-T curve) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG obtained from its −ΔS

_{m}-T curves and C

_{p}(T) curve (shown in the inset). The ΔT

_{ad}reaches a maximum value of ~1.05 K under 1.5 T and ~2.64 K under 5 T, respectively. These well-known magnetocaloric materials (such as Gd [54], Gd

_{5}(Si

_{2}Ge

_{2}) [7], MnAs [8] and Fe

_{49}Rh

_{51}[55]) undergo a first-order magnetic phase transition, exhibiting a giant magnetocaloric effect. Therefore, the magnetic entropy change curve shows extremely high sharp peaks within a narrow temperature range, and the magnetic entropy change peak value is much higher than that of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG with a second-order magnetic phase transition in this study. Therefore, the RCP of Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG is larger than that of famous magnetocaloric materials, but ΔT

_{ad}is smaller than of these materials. Considering its relatively high −ΔS

_{m}

^{peak}at 312.5 K, RCP and ΔT

_{ad}, the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG is a prospective candidate for an intermediate component of magnetic refrigerants with a table-shape −ΔS

_{m}curve within the interval between T

_{Cold}and T

_{Hot}of a domestic refrigerator.

_{m}

^{peak}near RT as much as possible seems to be an effective way to improve the magnetocaloric properties of Fe-based MGs. In the previous study of Fe-Ce-B ternary MGs [56], Ce was partially replaced by B, and it was found that with the decrease in Ce atoms, the antiferromagnetic coupling between Ce and Fe atoms was weakened, resulting in the enhancement of 3d-3d interaction between Fe atoms and thus T

_{c}increased. In the study of Fe-Zr-B ternary MGs [32], it was found that by replacing Zr with Ce, T

_{c}decreased from 306 K to 283 K. In summary, the composition dependence of the MCE in the Fe-Zr-Pr-B quaternary amorphous alloys system can be explained by the antiferromagnetic coupling between Ce and Fe atoms and the Ce-Pr interaction caused by the introduction of Ce atoms, which may lead to the weakening of the 3d-3d interaction between Fe atoms. Therefore, the substitution of Ce for Pr will reduce the T

_{c}of Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG. At the same time, because the magnetic moment of Ce atoms is lower than that of Pr atoms, the total magnetic entropy of the alloy will be reduced by the substitution of Ce for Pr, so the −ΔS

_{m}

^{peak}will be reduced. There are two reasons for choosing minor Ce to replace Pr in this research: firstly, Ce is cheaper than Pr, which can save costs; secondly, Ce and Pr are in adjacent positions in the periodic table of elements and the 4f shell is different from two electrons, which will not produce a large change. Based on the previous research results, it is expected that the total magnetic moment will not decrease too much while the minor Ce replaces Pr in reducing the T

_{c}of Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG, so it is more likely to obtain magnetocaloric materials with good magnetocaloric properties near RT.

## 4. Conclusions

_{88}Zr

_{4}Pr

_{4}B

_{4}MG, and the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon with a thickness of ~40 micrometer was successfully prepared. The influences of the minor Ce substitution for Pr on GFA, magnetic properties and magnetocaloric effect of the Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}MG, as well as their mechanisms, were further studied. The main conclusions are detailed below:

- (i)
- The T
_{rg}and γ indicate that the minor Ce substitution for Pr does not obviously change the glass formability of the Fe_{88}Zr_{4}Pr_{4}B_{4}MG, but the glass formability of both the two ribbons is enough to vitrify them into glassy ribbon. - (ii)
- The T
_{c}of the Fe_{88}Zr_{4}Pr_{3}B_{4}Ce_{1}ribbon decreases by 9 K compared with the Fe_{88}Zr_{4}Pr_{4}B_{4}MG, which may be closely related to the antiferromagnetic coupling of the Ce atom with the Fe atom. The Fe_{88}Zr_{4}Pr_{3}B_{4}Ce_{1}MG ribbon shows typical soft magnetic characteristics of fully amorphous alloys but slightly lower M_{s}than that of the Fe_{88}Zr_{4}Pr_{4}B_{4}MG at 200 K. The M^{2}-H/M plots at various temperatures indicate the typical SOMPT feature of the Fe_{88}Zr_{4}Pr_{3}B_{4}Ce_{1}MG. - (iii)
- According to the Maxwell Equation, the −ΔS
_{m}^{peak}of the Fe_{88}Zr_{4}Pr_{3}B_{4}Ce_{1}ribbon reaches 3.84 J/(kg × K) under 5 T at 312.5 K, which is slightly lower than that of the Fe_{88}Zr_{4}Pr_{4}B_{4}MG but still higher than the −ΔS_{m}^{peak}near 310 K of other amorphous alloys and even high entropy alloys reported in literature. - (iv)
- The n-T curve, the minimum n value and the normalized universal curve of the Fe
_{88}Zr_{4}Pr_{3}B_{4}Ce_{1}MG ribbon also indicate the typical magnetocaloric behaviors of fully amorphous alloys. The values of n and N obtained by the KF method deviate slightly from those obtained by the linear fitting of the field dependence of −ΔS_{m}^{peak}and RCP, which may be due to the error in multiple derivation of the KF method.

_{m}

^{peak}near 310 K, RCP (~646.3 J/kg under 5 T) and ΔT

_{ad}(~2.64 K under 5 T), the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG ribbon has great potential for application as an intermediate component of magnetic refrigerants with a flattened −ΔS

_{m}curve in a domestic refrigerator.

## Author Contributions

## Funding

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

- Gschneidner, K.A., Jr.; Pecharsky, V.K.; Tsokol, A.O. Recent developments in magnetocaloric materials. Rep. Prog. Phys.
**2005**, 68, 1479. [Google Scholar] [CrossRef] - Yu, B.F.; Gao, Q.; Zhang, B.; Meng, X.Z.; Chen, Z. Review on research of room temperature magnetic refrigeration. Int. J. Refrig.
**2003**, 26, 622–636. [Google Scholar] [CrossRef] - Gschneidner, K.A., Jr.; Pecharsky, V.K. Magnetocaloric Materials. Annu. Rev. Mater. Sci.
**2000**, 30, 387–429. [Google Scholar] [CrossRef] - De Oliveira, N.A.; von Ranke, P.J. Theoretical aspects of the magnetocaloric effect. Phys. Rep.
**2010**, 489, 89–159. [Google Scholar] [CrossRef] - Franco, V.; Blázquez, J.S.; Ipus, J.J.; Law, J.Y.; Moreno-Ramírez, L.M.; Conde, A. Magnetocaloric effect: From materials research to refrigeration devices. Prog. Mater. Sci.
**2018**, 93, 112–232. [Google Scholar] - Pecharsky, V.K.; Gschneidner, K.A., Jr. Magnetocaloric effect and magnetic refrigeration. J. Magn. Magn. Mater.
**1999**, 200, 44–56. [Google Scholar] [CrossRef] - Pecharsky, V.K.; Gschneidner, K.A., Jr. Giant magnetocaloric effect in Gd
_{5}(Si_{2}Ge_{2}). Phys. Rev. Lett.**1997**, 78, 4494. [Google Scholar] [CrossRef] - Wada, H.; Morikawa, T.; Taniguchi, K.; Shibata, T.; Yamada, Y.; Akishige, Y. Giant magnetocaloric effect of MnAs
_{1-x}Sb_{x}in the vicinity of first-order magnetic transition. Phys. B Condens. Matter**2003**, 328, 114–116. [Google Scholar] [CrossRef] - Yao, J.; Wang, P.; Mozharivskyj, Y. Tuning Magnetic and Structural Transitions through Valence Electron Concentration in the Giant Magnetocaloric Gd
_{5-x}Eu_{x}Ge_{4}Phases. Chem. Mater.**2012**, 24, 552–556. [Google Scholar] [CrossRef] - Hashimoto, T.; Kuzuhara, T.; Sahashi, M.; Inomata, K.; Tomokiyo, A.; Yayama, H. New application of complex magnetic materials to the magnetic refrigerant in an Ericsson magnetic refrigerator. J. Appl. Phys.
**1987**, 62, 3873–3878. [Google Scholar] [CrossRef] - Franco, V.; Blázquez, J.S.; Ingale, B.; Conde, A. The Magnetocaloric Effect and Magnetic Refrigeration Near Room Temperature: Materials and Models. Annu. Rev. Mater. Res.
**2012**, 42, 305–342. [Google Scholar] [CrossRef] - Luo, Q.; Wang, W.H. Magnetocaloric effect in rare-based bulk metallic glasses. J. Alloys Compd.
**2010**, 495, 209–216. [Google Scholar] [CrossRef] - Ma, L.Y.; Gan, L.H.; Chan, K.C.; Ding, D.; Xia, L. Achieving a table-like magnetic entropy change across the ice point of water with tailorable temperature range in Gd-Co-based amorphous hybrids. J. Alloys Compd.
**2017**, 723, 197–200. [Google Scholar] [CrossRef] - Wu, C.; Ding, D.; Xia, L.; Chan, K.C. Achieving tailorable magneto-caloric effect in the Gd-Co binary amorphous alloys. AIP Adv.
**2016**, 6, 035302. [Google Scholar] [CrossRef] - Bingham, N.S.; Wang, H.; Qin, F.; Peng, H.X.; Sun, J.F.; Franco, V.; Srikanth, H.; Phan, M.H. Excellent magnetocaloric properties of melt-extracted Gd-based amorphous microwires. Appl. Phys. Lett.
**2012**, 101, 102407. [Google Scholar] [CrossRef] - Tang, B.Z.; Xie, H.X.; Li, D.M.; Xia, L.; Yu, P. Microstructure and its effect on magnetic and magnetocaloric properties of the Co
_{50}Gd_{50-x}Fe_{x}glassy ribbons. J. Non-Cryst. Solids**2020**, 533, 119935. [Google Scholar] [CrossRef] - Wang, X.; Tang, B.Z.; Wang, Q.; Yu, P.; Ding, D.; Xia, L. Co
_{50}Gd_{48-x}Fe_{2}Ni_{x}amorphous alloys with high adiabatic temperature rise near the hot end of a domestic magnetic refrigerator. J. Non-Cryst. Solids**2020**, 544, 120146. [Google Scholar] [CrossRef] - Tang, B.Z.; Liu, X.P.; Li, D.M.; Yu, P.; Xia, L. Effect of Ni substitution on the formability and magnetic properties of Gd
_{50}Co_{50}amorphous alloy. Chin. Phys. B**2020**, 29, 056401. [Google Scholar] [CrossRef] - Álvarez, P.; Sánchez Llamazares, J.L.; Gorria, P.; Blanco, J.A. Enhanced refrigerant capacity and magnetic entropy flattening using a two-amorphous FeZrB(Cu) composite. Appl. Phys. Lett.
**2011**, 99, 232501. [Google Scholar] [CrossRef] - Lai, J.W.; Zheng, Z.G.; Zhong, X.C.; Franco, V.; Montemayor, R.; Liu, Z.W.; Zeng, D.C. Table-like magnetocaloric effect of Fe
_{88-x}Nd_{x}Cr_{8}B_{4}composite materials. J. Magn. Magn. Mater.**2015**, 390, 87–90. [Google Scholar] [CrossRef] - Yu, P.; Zhang, J.Z.; Xia, L. Effect of boron on the magneto-caloric effect in Fe
_{91-x}Zr_{9}B_{x}(x = 3, 4, 5) amorphous alloys. J. Mater. Sci.**2017**, 52, 13948–13955. [Google Scholar] [CrossRef] - Wang, X.; Wang, Q.; Tang, B.Z.; Ding, D.; Cui, L.; Xia, L. Magnetic and magneto-caloric properties of the amorphous Fe
_{92− x}Zr_{8}B_{x}ribbons. Materials**2020**, 13, 5334. [Google Scholar] [CrossRef] - Mishra, D.; Gurram, M.; Reddy, A.; Perumal, A.; Saravanan, P.; Srinivasan, A. Enhanced soft magnetic properties and magnetocaloric effect in B substituted amorphous Fe–Zr alloy ribbons. Mater. Sci. Eng. B
**2010**, 175, 253–260. [Google Scholar] [CrossRef] - Wu, Y.B.; Wang, Q.; Tang, B.Z.; Pan, L.L.; Ding, D.; Xia, L. Outstanding glass formability and magneto-caloric effect of a Fe
_{85}Co_{3}Zr_{5}B_{4}Nb_{3}metallic glass. J. Non-Cryst. Solids**2021**, 566, 120885. [Google Scholar] [CrossRef] - Chen, L.S.; Zhang, J.Z.; Wen, L.; Yu, P.; Xia, L. Outstanding magnetocaloric effect of Fe
_{88−x}Zr_{8}B_{4}Sm_{x}(x = 0, 1, 2, 3) amorphous alloys. Sci. China Phys. Mech. Astron.**2018**, 61, 056121. [Google Scholar] - Wang, Q.; Ding, D.; Tang, B.Z.; Yu, P.; Chan, K.C.; Xia, L. Excellent magnetocaloric performance of a Fe
_{88}Zr_{4}Pr_{4}B_{4}amorphous alloy and its amorphous hybrids. Intermetallics**2023**, 161, 107982. [Google Scholar] [CrossRef] - Wang, P.J.; Wang, Q.; Zheng, S.H.; Zhu, L.Z.; Ding, D.; Tang, B.Z.; Yu, P.; Yao, J.L.; Xia, L. Improvement of Curie temperature and magnetic entropy change of a Fe
_{88}Zr_{8}B_{4}metallic glass by minor Nd substitution. J. Non-Cryst. Solids**2023**, 611, 122347. [Google Scholar] [CrossRef] - Guo, D.Q.; Yuan, Y.D.; Chan, K.C. The effect of different minor additions on the magneto-caloric effect of FeZrB metallic ribbons near room temperature. J. Magn. Magn. Mater.
**2018**, 446, 12–17. [Google Scholar] [CrossRef] - Li, X.; Pan, Y. Magnetocaloric effect in Fe-Zr-B-M (M = Ni, Co, Al, and Ti) amorphous alloys. J. Appl. Phys.
**2014**, 116, 093910. [Google Scholar] [CrossRef] - Fang, Y.K.; Yeh, C.C.; Hsieh, C.C.; Wang, C.W.; Chang, H.W.; Chang, W.C.; Li, X.M.; Li, W. Magnetocaloric effect in Fe–Zr–B–M (M = Mn, Cr, and Co) amorphous systems. J. Appl. Phys.
**2009**, 105, 07A910. [Google Scholar] [CrossRef] - Gan, L.H.; Ma, L.Y.; Tang, B.Z.; Ding, D.; Xia, L. Effect of Co substitution on the glass forming ability and magnetocaloric effect of Fe
_{88}Zr_{8}B_{4}amorphous alloys. Sci. China Phys. Mech. Astron.**2017**, 60, 076121. [Google Scholar] [CrossRef] - Li, A.L.; Wang, Q.; Tang, B.Z.; Yu, P.; Ding, D.; Xia, L. Magnetocaloric effect of the Fe
_{87}M_{8}B_{5}(M = Zr, Ce) amorphous alloys. Mater. Sci. Eng. B**2022**, 286, 116033. [Google Scholar] [CrossRef] - Mozharivskyj, Y. Preparation of magnetocaloric materials. In Comprehensive Inorganic Chemistry III, 3rd ed.; Reedijk, J., Poeppelmeier, K.R., Eds.; Elsevier Ltd.: Amsterdam, The Netherlands, 2023; Volume 5, pp. 178–198. [Google Scholar]
- Turnbull, D. Under what conditions can a glass be formed? Contemp. Phys.
**1969**, 10, 473–488. [Google Scholar] [CrossRef] - Lu, Z.P.; Liu, C.T. A new glass-forming ability criterion for bulk metallic glasses. Acta Mater.
**2002**, 50, 3501–3512. [Google Scholar] [CrossRef] - Banerjee, B.K. On a generalised approach to first and second order magnetic transitions. Phys. Lett.
**1964**, 12, 16–17. [Google Scholar] [CrossRef] - Arrott, A.S. Generalized Curie-Weiss law. Phys. Rev. B
**1985**, 31, 2851. [Google Scholar] [CrossRef] - Zhang, Y.K.; Zhu, J.; Hao, Z.H.; Hao, W.X.; Mo, Z.J.; Li, L.W. Tunable magnetic phase transition and magnetocaloric effect in the rare-earth-free Al-Mn-Fe-Co-Cr high-entropy alloys. Mater. Des.
**2023**, 229, 111894. [Google Scholar] [CrossRef] - Zhang, Y.K.; Xu, P.; Zhu, J.; Yan, S.M.; Zhang, J.C.; Li, L.W. The emergence of considerable room temperature magnetocaloric performances in the transition metal high-entropy alloys. Mater. Today Phys.
**2023**, 32, 101031. [Google Scholar] [CrossRef] - Peng, J.X.; Tang, B.Z.; Wang, Q.; Bai, C.; Wu, Y.; Chen, Q.X.; Li, D.M.; Ding, D.; Xia, L.; Guo, X.L.; et al. Effect of heavy rare-earth (Dy, Tb, Gd) addition on the glass-forming ability and magneto-caloric properties of Fe
_{89}Zr_{7}B_{4}amorphous alloy. J. Alloys Compd.**2022**, 925, 166707. [Google Scholar] [CrossRef] - Wang, C.H.; Wang, Q.; Tang, B.Z.; Zhou, X.; Ding, D.; Xia, L. Achieve good magneto-caloric response near the ambient temperature in a Fe
_{86}La_{7}B_{5}Ce_{2}amorphous ribbon. J. Magn. Magn. Mater.**2022**, 547, 168954. [Google Scholar] [CrossRef] - Wood, M.E.; Potter, W.H. General analysis of magnetic refrigeration and its optimization using a new concept: Maximization of refrigerant capacity. Cryogenics
**1985**, 25, 667–683. [Google Scholar] [CrossRef] - Dubenko, I.; Ali, N.; Stadler, S.; Zhukov, A.; Zhukova, V.; Hernando, B.; Prida, V.; Prudnikov, V.; Gan’shina, E.; Granovsky, A. Magnetic, magnetocaloric, magnetotransport, and magneto-optical properties of Ni–Mn–In-Based Heusler alloys: Bulk, ribbons, and microwires. Nov. Funct. Magn. Mater. Springer Ser. Mater. Sci.
**2016**, 231, 41–83. [Google Scholar] - Pathak, A.K.; Dubenko, I.; Stadler, S.; Ali, N. Magnetic and magnetocaloric properties of Gd
_{6}X_{2}Si_{3}(X = Ni, Co) and Ln_{6}Co_{2}Si_{3}(Ln = Pr, La). J. Appl. Phys.**2011**, 109, 07A913. [Google Scholar] [CrossRef] - Franco, V.; Blázquez, J.S.; Conde, A. Field dependence of the magnetocaloric effect in materials with a second order phase transition: A master curve for the magnetic entropy change. Appl. Phys. Lett.
**2006**, 89, 222512. [Google Scholar] [CrossRef] - Fisher, M.E. The theory of equilibrium critical phenomena. Rep. Prog. Phys.
**1967**, 30, 615–730. [Google Scholar] [CrossRef] - Kouvel, J.S.; Fisher, M.E. Detailed Magnetic Behavior of Nickel Near its Curie Point. Phys. Rev.
**1964**, 136, A1626. [Google Scholar] [CrossRef] - Gębara, P.; Hasiak, M. Investigation of critical behavior in the vicinity of ferromagnetic to paramagnetic phase transition in the Fe
_{75}Mo_{8}Cu_{1}B_{16}alloy. J. Appl. Phys.**2018**, 124, 083904. [Google Scholar] [CrossRef] - Hiroyoshi, H.; Hoshi, A.; Nakagawa, Y. Arrott-Noakes plots near the Curie temperature of Fe
_{3}Pt: Ordered and disordered alloys in high magnetic fields. J. Appl. Phys.**1982**, 53, 2453–2455. [Google Scholar] [CrossRef] - Oesterreicher, H.; Parker, F.T. Magnetic cooling near Curie temperatures above 300 K. J. Appl. Phys.
**1984**, 55, 4334–4338. [Google Scholar] [CrossRef] - Franco, V.; Conde, A. Scaling laws for the magnetocaloric effect in second order phase transitions: From physics to applications for the characterization of materials Lois d’échelle gouvernant l’effet magnétocalorique des transitions de phase de seconde ordre: De la physique aux applications permettant de caractériser les matériaux. Int. J. Refrig.
**2010**, 33, 465–473. [Google Scholar] - Widom, B. Equation of State in the Neighborhood of the Critical Point. J. Chem. Phys.
**1965**, 43, 3898–3905. [Google Scholar] [CrossRef] - Franco, V.; Blázquez, J.S.; Conde, A. The influence of Co addition on the magnetocaloric effect of Nanoperm-type amorphous alloys. J. Appl. Phys.
**2006**, 100, 064307. [Google Scholar] [CrossRef] - Dan’kov, S.Y.; Tishin, A.M.; Pecharsky, V.K.; Gschneidner, K.A., Jr. Magnetic phase transitions and the magnetothermal properties of gadolinium. Phys. Rev. B
**1998**, 57, 3478–3490. [Google Scholar] [CrossRef] - Nikitin, S.A.; Myalikgulyev, G.; Tishin, A.M.; Annaorazov, M.P.; Asatryan, K.A.; Tyurin, A.L. The magnetocaloric effect in Fe
_{49}Rh_{51}compound. Phys. Lett. A**1990**, 148, 363–366. [Google Scholar] [CrossRef] - Zheng, S.H.; Wang, Q.; Zhu, L.Z.; Wang, P.J.; Ding, D.; Tang, B.Z.; Yu, P.; Yao, J.L.; Xia, L. Excellent Magnetocaloric Performance of the Fe
_{87}Ce_{13}-xBx (x = 5, 6, 7) Metallic Glasses and Their Composite. Materials**2023**, 16, 4393. [Google Scholar] [CrossRef] [PubMed]

**Figure 1.**(

**a**) XRD pattern of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as-spun ribbon measured at the scanning speed of 1 °/min: the upper-left is the cross-section morphology, the upper-right is the prepared sample; (

**b**) The DSC traces and melting behaviors (inset) of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}as-spun ribbon.

**Figure 2.**(

**a**) M-T curve of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon measured under a field of 0.03 T, the inset is the (dM/dT)-T curve; (

**b**) Hysteresis loops of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon measured at 200 K and 380 K under 5 T.

**Figure 3.**(

**a**) Isothermal M-H curves of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon at various temperatures under 5 T; (

**b**) Arrott plots of Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon.

**Figure 4.**(

**a**) −ΔS

_{m}-T curves under various magnetic fields of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon; (

**b**) The effective magnetic moment of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}and Fe

_{88}Zr

_{4}Pr

_{4}B

_{4}amorphous ribbons; (

**c**) −ΔS

_{m}-T curves under 5 T of several Fe-based amorphous alloys with peak temperature near 310 K.

**Figure 5.**(

**a**) The n-T curve of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon, the inset is the linear fitting of the ln(−ΔS

_{m}

^{peak}) vs. ln(H) at 312.5 K; (

**b**) Temperature dependence of M

_{st}(T) and χ

_{0}(T)

^{−1}of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon; (

**c**) The ln(M) vs. ln(H) plot at 315 K of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG; (

**d**) The ln(RCP)-ln(H) plot of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}MG.

**Figure 6.**(

**a**) Universal curves for Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon under different magnetic fields; (

**b**) ΔT

_{ad}-T curves of the Fe

_{88}Zr

_{4}Pr

_{3}B

_{4}Ce

_{1}amorphous ribbon under 1.5 T and 5 T, the inset is its C

_{p}(T) curve.

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**MDPI and ACS Style**

Zhu, L.-Z.; Wang, Q.; Zheng, S.-H.; Wang, P.-J.; Ding, D.; Tang, B.-Z.; Yu, P.; Yao, J.-L.; Xia, L.
Effect of Minor Ce Substitution for Pr on the Glass Formability and Magnetocaloric Effect of a Fe_{88}Zr_{4}Pr_{4}B_{4} Metallic Glass. *Metals* **2023**, *13*, 1531.
https://doi.org/10.3390/met13091531

**AMA Style**

Zhu L-Z, Wang Q, Zheng S-H, Wang P-J, Ding D, Tang B-Z, Yu P, Yao J-L, Xia L.
Effect of Minor Ce Substitution for Pr on the Glass Formability and Magnetocaloric Effect of a Fe_{88}Zr_{4}Pr_{4}B_{4} Metallic Glass. *Metals*. 2023; 13(9):1531.
https://doi.org/10.3390/met13091531

**Chicago/Turabian Style**

Zhu, Li-Ze, Qiang Wang, Shu-Hui Zheng, Peng-Jie Wang, Ding Ding, Ben-Zhen Tang, Peng Yu, Jin-Lei Yao, and Lei Xia.
2023. "Effect of Minor Ce Substitution for Pr on the Glass Formability and Magnetocaloric Effect of a Fe_{88}Zr_{4}Pr_{4}B_{4} Metallic Glass" *Metals* 13, no. 9: 1531.
https://doi.org/10.3390/met13091531