圖1   位錯(cuò)滑移型金屬基體及其與納米線匹配的二維點(diǎn)陣示意圖,當(dāng)位錯(cuò)(兩根位錯(cuò))滑移至界面時(shí)位錯(cuò)滑移基體輸出應(yīng)變的分布示意圖

Fig.1   Two-dimension lattice schematic of the strain match between the nanowire and the dislocation slip matrix(a) matrix before dislocation slip(b) formed Burgers step (red line) after dislocation slip(c) atomic-scale high stress concentration (dotted circle) was generated when the dislocation moves to the interface between the nanowire and the matrix(d) schematic of the strain (ε) distribution when the dislocation slips to the interface, which shows the inelastic shear strain of matrix (${?}_{\mathrm{disl}}^{\mathrm{matrix}}$) approaches 100% around dislocation and elastic strain of matrix (${?}_{\mathrm{el}}^{\mathrm{matrix}}$) of about 0.2% away the dislocation

圖2   點(diǎn)陣切變基體與納米線匹配的二維點(diǎn)陣及應(yīng)變分布示意圖,基體發(fā)生應(yīng)力誘發(fā)馬氏體變形(馬氏體和母相共存)過程中點(diǎn)陣切變基體輸出應(yīng)變的分布示意圖

Fig.2   Two-dimension lattice schematic of the strain match between the nanowire and the lattice shear matrix(a) matrix before lattice shear(b) matrix after lattice shear(c) interface between the nanowire and the matrix after lattice shear, showing no atomic-scale high stress concentration(d) schematic of the strain distribution when the matrix experiences the stress induced martensitic transformation, which shows the elastic strain of matrix (${?}_{\mathrm{P}}^{\mathrm{matrix}}$) of about 1% around parent and shear strain of matrix (${?}_{\mathrm{M}}^{\mathrm{matrix}}$) approaches 7% around martensite. This 7% strain matches the elastic strain of the nanowire (${\mathrm{\epsilon }}_{\mathrm{el}}^{\mathrm{nanowire}}$) of about 6% (red line)

圖3   Nb納米線/NiTi基體復(fù)合材料絲材及其微觀組織[12]

Fig.3   The macro and micro images of the nanowire Nb/NiTi composite[12]
(a) a coil of composite wire with a diameter of 0.5 mm
(b) scanning TEM image of the cross section of composite wire (bright regions, cross sections of Nb nanowires; dark regions, NiTi matrix)
(c) TEM image of a longitudinal section of composite wire (NW indicates nanowire)
(d) macroscopic appearance of a bundle of freestanding Nb nanowires
(e, f) SEM images of the freestanding Nb nanowires

圖4   Nb納米線/NiTi記憶合金樣品在原位拉伸過程中的高能同步輻射XRD譜以及Nb納米線的晶格應(yīng)變曲線[12]

Fig.4   The high energy synchrotron XRD of the nanowire Nb/NiTi sample during tensile test and the evolution of the lattice strain with respect to the applied strain of Nb nanowire[12](a) the diffraction peak of the Nb (220) plane perpendicular to the loading direction shifts obviously when the NiTi showing the stress induced martensitic transformation (SIMT—stress-induced martensitic transformation)(b) the diffraction peak of the Nb (220) plane perpendicular to the loading direction shifts slightly when the NiTi showing plastic deformation(c) evolution of the lattice strain with respect to the applied strain for Nb (220) planes

圖5   Nb納米線在位錯(cuò)滑移型金屬基體中在應(yīng)力誘發(fā)馬氏體相變NiTi基體中的彈性應(yīng)變極限,與文獻(xiàn)報(bào)道的多種自由態(tài)納米線的彈性應(yīng)變極限的比較[12]

Fig.5   Comparison of the elastic strain limits of Nb nanowires embedded in the matrix deforming by dislocation slip (1), Nb nanowires embedded in the matrix deforming by SIMT (2), and some freestanding nanowires (3)[12]

圖6   Nb納米線/NiTi記憶合金復(fù)合材料(NICSMA)的拉伸應(yīng)力-應(yīng)變曲線、NICSMA性能占據(jù)三大類工程材料性能挑戰(zhàn)區(qū)、NICSMA與其它金屬材料屈服強(qiáng)度和彈性應(yīng)變極限的比較、與其它材料屈服強(qiáng)度和彈性模量的比較[12]

Fig.6   Tensile stress-strain curves of the nanowire in situ composite with shape memory alloy (NICSMA) composite (εe—elastic limit, σs—yield strength, E—elastic modulus) (a), comparison of strengths and elastic strains of ceramics, metals, polymers and our composite (marked by NICSMA) (b), comparison of the yield strengths and elastic strain limits of different materials (c), comparison of the yield strengths and Young's moduli of different materials (d)[12]

圖7   Nb納米線/NiTi記憶合金樣品的拉伸循環(huán)應(yīng)力-應(yīng)變曲線、樣品在第一次加載過程中的同步輻射高能XRD譜、納米線在第一次加卸載過程中的晶格應(yīng)變曲線、納米線在第二次加卸載過程中的晶格應(yīng)變曲線[13]

Fig.7   The cyclic tensile stress-strain curve of the nanowire in situ composite with shape memory alloy sample (a), evolution of the diffraction peaks for Nb (220), B2-NiTi (211) and B19'-NiTi (001) planes perpendicular to the loading direction during loading (b), evolution of the lattice strain with respect to the applied strain for Nb (220) plane perpendicular to the loading direction during the first cycle (c), evolution of the lattice strain with respect to the applied strain for Nb (220) plane perpendicular to the loading direction during the second cycle (d)[13]

圖8   Nb納米線體積分?jǐn)?shù)分別為10%和20%的NiTi記憶合金復(fù)合材料絲材的電子顯微分析[14]

Fig.8   TEM analyses of two NiTi shape memory alloy composites with 10% and 20% volume fraction Nb nanowire[14]
(a, b) SAED patterns of longitudinal view of the two samples(c, d) TEM bright field images of the two samples corresponding to Figs.8a and b(e, f) HAADF images of the two sample(g, h) HRTEM image revealing the interfaces between a Nb nanowire and NiTi matrix

圖9   在原位TEM拉伸過程中Nb納米線的彈性變形行為[15]

Fig.9   TEM study of lattice strain matching between Nb nanowires and the NiTi matrix[15]
(a) bright feld image of a microbeam fabricated by means of focus ion beam milling(b) enlarged view of a Nb nanowire in the beam(c) HRTEM image of the region marked as c in Fig.9b(d) TEM image of the microbeam upon loading to about 3.23% strain(e) enlarged TEM image of the region marked as e in Fig.9d, showing the three martensite plates (marked as M1, M2 and M3) nucleated in the NiTi matrix(f~h) HRTEM images of the regions marked as f, g and h in Fig.9e(i~l) filtered HRTEM images of the regions marked as i in Fig.9c and as j~l in Figs.9f~h

圖10   包含M1和M3馬氏體板條區(qū)域的高分辨像及Nb納米線中晶格應(yīng)變的變化規(guī)律[15]

Fig.10   HRTEM image of the region covering martensite plates M1 and M3. The interplanar spacing variation was calculated at an interval of seven (110)Nb planes (a) and distribution of the lattice strain as a function of distance from the start plane (b)[15]

圖11   Nb納米帶/NiTi基體復(fù)合材料絲的橫截面和縱截面的STEM照片、垂直于加載方向的Nb (220)晶面的晶格應(yīng)變與施加應(yīng)變的關(guān)系曲線(插圖為樣品在室溫下的拉伸應(yīng)力-應(yīng)變曲線)[12]

Fig.11   STEM images of a cross-section (a) and a longitudinal-section (b) of a ribbion Nb/NiTi composite, evolution of the d-spacing strain with respect to the applied macroscopic strain for the Nb (220) plane perpendicular to the loading direction (Inset shows the stress-strain curve of the sample at room temperature) (c)[12]

圖12   Nb(110)晶面晶格應(yīng)變與施加應(yīng)變的關(guān)系曲線(插圖是Nb納米線/NiTi記憶合金復(fù)合材料拉伸應(yīng)力-應(yīng)變曲線)、在加載過程中B19′-NiTi(001)晶面的衍射強(qiáng)度與二維X射線衍射譜方位角的關(guān)系曲線、在8.7%循環(huán)前后馬氏體態(tài)NiTi基體中孿晶形貌的比較、納米線的彈性應(yīng)變極限與以往文獻(xiàn)報(bào)道的比較[16]

Fig.12   Evolution of d-spacing strain with respect to applied strain for the Nb (110) plane perpendicular to the wire axial direction during tensile loading (Inset is the macroscopic stress-strain curve of the NICSMA composite) (a), evolution of X-ray diffraction intensity of B19′-NiTi <001> planes versus the azimuth angle during tensile loading (b), TEM micrographs of twin morphologies of the martensitic NiTi matrix before and after a tensile deformation cycle to 8.7% (c), comparison of the elastic strain limits of Nb nanowires embedded in the matrix deforming by dislocation slip (1), Nb nanowires embedded in the matrix deforming by detwinning (2), and some freestanding nanowires (3) (d)[16]

圖13   Nb納米線/NiTi記憶合金復(fù)合材料在加卸載過程中Nb納米線的晶格應(yīng)變隨外加應(yīng)變變化曲線、復(fù)合材料在加載過程中的應(yīng)力-應(yīng)變曲線以及與商業(yè)化NiTi記憶合金的對比[17]

Fig.13   The d-spacing strain with respect to applied macroscopic strain for the Nb (110) planes perpendicular to the loading direction in the NiTi-Nb composite (a), comparison of tensile stress-strain curves of the composite wire (red curve) and a commercial superelastic NiTi wire (yellow curve) (b)[17]

圖14   Nb納米線/NiTi記憶合金復(fù)合材料及其與單體NiTi超彈性曲線的對比[18]

Fig.14   The tensile cyclic stress-strain curves of the nanostructured Nb reinforced NiTi shape memory alloy composite wire (strain: 4% and 5%); the tensile cyclic stress-strain curve of a commercial superelastic NiTi shape memory alloy wire[18]

圖15   Ti3Sn/TiNi復(fù)合材料微觀組織結(jié)構(gòu)[19]

Fig.15   Typical microstructure of the TiNi-Ti3Sn composite[19]
(a) SEM backscattered electron images of the composite. The inset shows the Ti3Sn (light)-TiNi (dark) lamellar structure at high magnification
(b) TEM bright-field image of the composite. The inset shows the button ingot of the composite
(c) HRTEM image of the interface between TiNi and Ti3Sn
(d, e) display selected-area electron diffraction patterns of the Ti3Sn and TiNi lamellae, respectively, shown in Fig.15b
(f) one-dimensional high-energy X-ray diffraction (HE-XRD) pattern of the composite. The inset contains its corresponding two-dimensional HE-XRD pattern

圖16   Ti3Sn/TiNi復(fù)合材料變形行為[19]

Fig.16   Deformation behavior of the TiNi-Ti3Sn composite[19]
(a) the lattice strain evolutions of B19'-TiNi (022) and Ti3Sn (201) planes perpendicular to the loading direction as a function of the applied macroscopic strain. The inset shows an enlarged view of the lattice strain curve of the TiNi in the initial stages of deformation
(b) the comparison of the elastic strains of Ti3Sn achieved in our composite with different reinforcements (such as nanowires, laminates, and particles) embedded in conventional metal matrices, which are deformed by dislocation slip

圖17   Ti3Sn/TiNi復(fù)合材料的的室溫壓縮應(yīng)力應(yīng)變曲線、復(fù)合材料的力學(xué)性能和其它的高性能金屬基復(fù)合材料對比[19]

Fig.17   Room-temperature compressive stress-strain curve of the composite (a), comparison of the mechanical properties of our composite with those of other high-performance metal-based lamellar composites in which the soft component is a conventional metal (without the "J-curve" deformation attributes) rather than the biopolymer-like metal ("J-curve" deformation attributes) (b)[19]

圖18   復(fù)合材料絲雙程驅(qū)動特性[20]

Fig.18   Two-way actuated properties of the composite wire[20]
(a) output strain-temperature curve of the composite without external load
(b) evolution of d-spacing strain with respect to temperature for the Nb (110) plane perpendicular to the wire axial direction

圖19   Nb納米線/NiTi復(fù)合材料在拉伸循環(huán)過程中的一維高能XRD譜、NiTi基體中Nb納米線被保留彈性應(yīng)變與拉伸應(yīng)變的曲線、NiTi基體中Nb納米線被保留拉伸和壓縮彈性應(yīng)變與文獻(xiàn)報(bào)道的基材表面薄膜被保留拉伸和壓縮彈性應(yīng)變的比較[16]

Fig.19   Evolution of high-energy X-ray diffraction peaks for Nb (110) and B19′-NiTi (001) planes through the multiple-step tensile cycles (a), evolution of d-spacing strain with respect to applied strain for the Nb (110) plane perpendicular to the wire axial direction during the multiple-step tensile cycles (b), comparison of the retained tensile and compressive elastic strains of large quantity Nb nanowires in the composite without external load and those of the reported thin films on substrates and embedded nanoinclusions in films (c)[16]

圖20   不同應(yīng)變狀態(tài)的10 nm Pt和5 nm Pt納米膜的氧還原反應(yīng)(ORR)線性伏安掃描(LSV)曲線對比[28]

Fig.20   Polarization curves of the oxygen reduction reaction (ORR) of 10 and 5 nm Pt nanofilm under different strain states at a scan rate of 0.3 V/s. The data of 10 nm Pt nanofilm are shown with standard deviation[28]