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Stress, strain, and temperature curves of shape memory polymer.
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The shape memory polymer (SMP) is a new type of smart material that can produce a shape memory effect through the stimulation of the external environment. In this article, the viscoelastic constitutive theory of the shape memory polymer and the mechanism of the bidirectional memory effect of the shape memory polymer are described. A chiral poly cel...
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... deformation of a shape memory polymer can be controlled with a heat source, and the shape memory effect is generated in this process. The relationship between temperature, stress, and strain is shown in Figure 2 [25]. Materials 2023, 16, x FOR PEER REVIEW 3 of 18 cell based on a shape memory polymer using the finite element method. ...
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... deformation of a shape memory polymer can be controlled with a heat source, and the shape memory effect is generated in this process. The relationship between temperature, stress, and strain is shown in Figure 2 [25]. The mechanical response of the shape memory polymer is related to ambient temperature, loading history, loading time, etc., as shown in Figure 2. The material is in a Figure 2. Stress, strain, and temperature curves of shape memory polymer. ...
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... relationship between temperature, stress, and strain is shown in Figure 2 [25]. The mechanical response of the shape memory polymer is related to ambient temperature, loading history, loading time, etc., as shown in Figure 2. The material is in a Figure 2. Stress, strain, and temperature curves of shape memory polymer. ...
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... relationship between temperature, stress, and strain is shown in Figure 2 [25]. The mechanical response of the shape memory polymer is related to ambient temperature, loading history, loading time, etc., as shown in Figure 2. The material is in a Figure 2. Stress, strain, and temperature curves of shape memory polymer. ...
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... mechanical response of the shape memory polymer is related to ambient temperature, loading history, loading time, etc., as shown in Figure 2. The material is in a glassy state when the temperature of the shape memory polymer is below T g , and it can be regarded as a linear elastic material. ...
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... define the two types of scaffolds as scaffold A and scaffold B, as shown in Figures 20 and 21. In Figure 20a showing scaffold A, the structural parameters of the scaffold bonded to the lateral ligament are h = 3(R − r) and H = a. In Figure 20b, the structural parameters of the scaffold bonded to the ligaments on the upper and lower sides are h = 3(R − r), and, where H is the length of the ligaments between the upper and lower rings, l = H /12. In Figure 21, scaffold B controls α by changing the middle two circles on the cell, and the structural parameters of the scaffold are l = (U − 2R)/12 and h = 3(R − r). ...
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... Figure 20a showing scaffold A, the structural parameters of the scaffold bonded to the lateral ligament are h = 3(R − r) and H = a. In Figure 20b, the structural parameters of the scaffold bonded to the ligaments on the upper and lower sides are h = 3(R − r), and, where H is the length of the ligaments between the upper and lower rings, l = H /12. In Figure 21, scaffold B controls α by changing the middle two circles on the cell, and the structural parameters of the scaffold are l = (U − 2R)/12 and h = 3(R − r). ...
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... process of automatic adjustment assisted by elastic scaffold A is shown in Figure 22. The process is divided into five steps. ...
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... process of automatic adjustment assisted by elastic scaffold A is shown in Figure 22. The process is divided into five steps. ...
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... repeatedly heating the complex to 100 • C or cooling it to 20 • C can achieve autonomous adjustment of the cell Poisson's ratio from positive to negative. The temperature changes and cell strain of the shape memory polymer are shown in Figure 23. ...
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... process of automatic adjustment assisted by elastic scaffold A is shown in Figure 22. The process is divided into five steps. ...
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... to 100℃ The process of automatic adjustment is assisted by elastic scaffold B, as shown in Figure 24. ...
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... repeatedly heating the complex to 100°C or cooling it to 20°C can achieve autonomous adjustment of the cell Poisson's ratio from positive to negative. The temperature changes and cell strain of the shape memory polymer are shown in Figure 25. The process of automatic adjustment is assisted by elastic scaffold B, as shown in Figure 24. ...
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... temperature changes and cell strain of the shape memory polymer are shown in Figure 25. The process of automatic adjustment is assisted by elastic scaffold B, as shown in Figure 24. ...
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... repeatedly heating the complex to 100 • C or cooling it to 20 • C can achieve autonomous adjustment of the cell Poisson's ratio from positive to negative. The temperature changes and cell strain of the shape memory polymer are shown in Figure 25. Materials 2023, 16, x FOR PEER REVIEW 15 of 18 Figure 23. ...
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... process of automatic adjustment is assisted by elastic scaffold B, as shown in Figure 24. ...
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... repeatedly heating the complex to 100°C or cooling it to 20°C can achieve autonomous adjustment of the cell Poisson's ratio from positive to negative. The temperature changes and cell strain of the shape memory polymer are shown in Figure 25. In Figures 24 and 15, whether α = 60° to α= 65° and whether β = 1:3 to β = 1:4, the maximum strain value is 0.4, the minimum strain value is 0, and the strain trend is the same. ...
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Citations
... Liu et al. [138] created a 4D-printed structure with a zero Poisson's ratio that could automatically adjust stiffness, energy absorption, and vibration isolation capability with temperature changes and exhibited excellent low-frequency vibration isolation without causing stiffness or strength degradation (Fig. 8B). Zhao et al. [139] designed a composite structure with a 2-way SME. The Poisson's ratio of the structure could change with the structural parameters and could even be converted between positive and negative. ...
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... The rock breaking efficiency of high-pressure water jets is influenced by various factors such as nozzle structure, flow field characteristics, jet pressure, and the physical properties of coal and rock, which makes the process of jet rock breaking extremely complex [16][17][18][19]. With the development of numerical simulation technology, material crushing and its change process analysis can be better reflected [20]. Numerical simulation methods have provided possibilities for studying the dynamic fragmentation process of rocks and analyzing the changes in their stress during water jet impact [21]. ...
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... Specific mechanical properties exhibit cell structures with a negative Poisson's ratio. Different properties compared to conventional metamaterials are caused by the auxetic effect [15,16]. ...
The current development of additive technologies brings not only new possibilities but also new challenges. One of them is the use of regular cellular materials in various components and constructions so that they fully utilize the potential of porous structures and their advantages related to weight reduction and material-saving while maintaining the required safety and operational reliability of devices containing such components. It is therefore very important to know the properties of such materials and their behavior under different types of loads. The article deals with the investigation of the mechanical properties of porous structures made by the Direct Metal Laser Sintering (DMLS) of Inconel 718. Two types of basic cell topology, mono-structure Gyroid (G) and double-structure Gyroid + Gyroid (GG), with material volume ratios of 10, 15 and 20 %, were studied within our research to compare their properties under quasi-static compressive loading. The testing procedure was performed at ambient temperature with a servo-hydraulic testing machine at three different crosshead testing speeds. The recorded data were processed, while the stress–strain curves were plotted, and Young’s modulus, the yield strength Re0.2, and the stress at the first peak of the local maximum σLocMax were identified. The results showed the best behavior under compression load among the studied structures displayed by mono-structure Gyroid at 10 %. At the same time, it can be concluded that the wall thickness of the structure plays an important role in the compressive properties but on the other hand, crosshead speed doesn´t influence results significantly.
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