## 4 Conclusions  
Fundamental analysis of the shape deformation of SC Ni-Mn-Ga alloys induced by a compressive field (\(\sigma\)-field) or a magnetic field (\(H\)-field) has been investigated. In addition, the SC Ni-Mn-Ga particles were integrated with two different polymers of epoxy resin or silicone rubber. These specimens were prepared to solve the conventional brittleness problem and also for the analysis of shape deformation. Important findings are listed below. 1. In the thermal analysis of the SC Ni-Mn-Ga particles, the \(M_{\mathrm{f}}\), \(M_{\mathrm{s}}\), \(A_{\mathrm{s}}\), and \(A_{\mathrm{f}}\) were determined to be 19 \({}^{\circ}\)C, 37 \({}^{\circ}\)C, 34 \({}^{\circ}\)C, and 53 \({}^{\circ}\)C, respectively, which are in good agreement with those found in the literature. A martensite phase at RT was therefore confirmed. 2. For the phase identification, it was found that the SC Ni-Mn-Ga particles were composed of the single 5M martensite phase at room temperature. 3. The SC Ni-Mn-Ga ingots were successfully fabricated via the floating zone method. These [100]\({}_{\mathrm{p}}\) SC Ni-Mn-Ga cubes with various dimensions were prepared based on the crystallographic identification. 4. In the compression test of the [100]\({}_{\mathrm{p}}\) SC Ni-Mn-Ga cubes, it was found that the martensite variant reorientation (MVR) took place from around 0.5 MPa and proceeded until approximately 1.5 MPa. A clear stress plateau, which was discerned in the \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**Externally Applied Field**} \\
**Material** & **Compressive** & **Magnetic** & **Corresponding Figure** \\ \hline SC Ni-Mn-Ga cube & \(\sigma_{\mathrm{MVR}}\) = \(\sim\)0.5 MPa & \(H_{\mathrm{MVR}}\) = \(\sim\)2.5 kOe & Figures 5 and 6 \\  & Rotation and MVR & & \\ One-particle composite & Free: \(h_{0}/w_{0}\) = 1.34 & – & Figures 9 and 10 \\  & \multicolumn{3}{c}{Pressed: \(h_{1}/w_{1}\) = 1.31} \\ SC Ni-Mn-Ga particles/polymer composite & Obvious MVR & No clear MVR & Figures 12 and 13 \\ \hline \hline \end{tabular} Note: \(\sigma_{\mathrm{MVR}}\) = Stress for martensite variant reorientation; \(H_{\mathrm{MVR}}\) = Magnetic field for martensite variant reorientation; \(h_{0}/w_{0}\) = Aspect ratio of the relatively large particle before compression; \(h_{1}/w_{1}\) = Aspect ratio of the relatively large particle after compression.  
\end{table} 
Table 3: Summary of the shape deformations of the [100]\({}_{\mathrm{p}}\) SC Ni-Mn-Ga cube and the composites, which were triggered by two different fields (e.g., compressive or magnetic fields). (Specific terms are denoted in the bottom column and the corresponding figures are shown in the right-hand side column. )stress-strain curve, indicates the commencement and proceeding of the MVR. Stress for the MVR is also in good agreement with that found in the literature. 5. In the magnetization-magnetic field (_M_-_H_) curve, it was observed that a sudden \"jump\" of the magnetization of the [100]\({}_{\text{p}}\) SC Ni-Mn-Ga cube took place as the magnetic field was increase to around 2.5 kOe. This indicates the MVR was initiated by the introduction of a magnetic field at this specific magnetic field value. 6. A relatively large SC Ni-Mn-Ga particle (one-particle/epoxy composite) was integrated with epoxy and served as a preliminary trial for the series of composites. An obvious rotation and a shape deformation were found in this relatively large SC Ni-Mn-Ga particle. The shape deformation through the analysis of the ratios of \(h_{\text{x}}/w_{\text{x}}\) (where \(x=0\) and 1) can be evidence of the MVR under a compressive field. Following this, the relatively small SC particles composite also confirmed a clear observation by using \(\upmu\)CT.
7. Following the synthesis and analysis of the one-particle/epoxy composite, the SC Ni-Mn-Ga particles with the dimensions of 100-160 \(\upmu\)m were integrated with two different polymers, respectively, in various volume percentages (i.e., 10, 20, and 40 vol.%). 8.