【摘要】：剪切增稠膠(Shear Thickening Gel,STG)是一種類似橡皮泥的非晶線性聚合物。在低應(yīng)變速率下,表現(xiàn)出流體特性;受到?jīng)_擊時,迅速變硬,表現(xiàn)出固體特性;并且沖擊過后可恢復(fù)到初始狀態(tài)。由于STG在液-固轉(zhuǎn)換過程中吸收大量的能量,因此被廣泛用于減震、防護(hù)領(lǐng)域。目前針對STG力學(xué)性能表征和性能改善的研究尚處于初級階段,特別的對其能量吸收能力與其力學(xué)性能對應(yīng)關(guān)系的認(rèn)識還不夠透徹。本論文首先采用流變儀探究STG在剪切模式下的力學(xué)參數(shù)隨剪切應(yīng)變幅值、激勵頻率變化關(guān)系,分析粘彈性與能量吸收能力的相關(guān)性。其次通過無機(jī)粒子摻雜,分析不同粒子改性后STG力學(xué)性能,得到性能優(yōu)異的STG。最后,運(yùn)用力學(xué)性能改善后的STG,設(shè)計得到阻尼、剛度自我協(xié)調(diào)的非線性彈簧。本文針對剪切模式STG流變性能和非線性彈簧關(guān)鍵問題展開研究,對于評價STG、理解STG微觀結(jié)構(gòu)變化以及STG的應(yīng)用研究具有十分重要意義。本論文主要研究成果如下:1)純STG采用大振幅振蕩剪切(LAOS)實(shí)驗,界定其材料線性、非線性區(qū)域,分析粘彈性能與能量吸收能力的相關(guān)性。由應(yīng)變掃描及其相應(yīng)的應(yīng)力-應(yīng)變曲線分析表明剪切應(yīng)變幅值2%為STG線性到非線性轉(zhuǎn)變臨界應(yīng)變點(diǎn)。STG由類液態(tài)變?yōu)轭惞虘B(tài),臨界轉(zhuǎn)換頻率為7Hz,在液固轉(zhuǎn)換區(qū)域STG具有優(yōu)異的能量吸收能力。2)采用無機(jī)粒子(CaCO_3、SiC、ZrO2)對STG力學(xué)性能改性。測試相同粒子不同質(zhì)量分?jǐn)?shù)、相同質(zhì)量分?jǐn)?shù)不同粒子剪切模式下力學(xué)性能,對模量變化、損耗因數(shù)、復(fù)合粘度變化及其相應(yīng)的應(yīng)力-應(yīng)變曲線分析,表明CaCO_3在力學(xué)性能改善方面具有顯著優(yōu)勢。3)基于STG設(shè)計出非線彈簧具有自適應(yīng)變剛度、變阻尼特性,在單軸壓縮測試條件下STG非線性彈簧最大剛度為7N/mm。在頻率為10Hz動態(tài)測試條件下STG非線性彈簧最大剛度達(dá)到98N/mm是單軸壓縮下測試時14倍。隨著頻率增加,遲滯回線形狀也越來越飽滿,具有很強(qiáng)自我協(xié)調(diào)特性。為了將STG更好用于減震防護(hù)領(lǐng)域,對STG線性、非線性界定,在非線性區(qū)域時STG內(nèi)部組織結(jié)構(gòu)破壞,在工程應(yīng)用中需避免。設(shè)計STG非線性彈簧在輕微振動條件下有很好的柔性性能,劇烈振動條件下有很好的變剛度特性,進(jìn)一步推動STG實(shí)用化發(fā)展。
[Abstract]:Shear thickening adhesive (Shear Thickening) is a kind of amorphous linear polymer similar to puree. At low strain rate, it exhibits fluid characteristics; when it is impacted, it harms quickly and exhibits solid properties; and it can be restored to its initial state after impact. Because STG absorbs a lot of energy in the process of liquid-solid conversion, it is widely used in the field of shock absorption and protection. At present, the study on the characterization and improvement of mechanical properties of STG is still in the primary stage, especially the understanding of the relationship between its energy absorption capacity and its mechanical properties is not enough. In this paper, the rheometer is used to study the relationship between the mechanical parameters of STG under shear mode and the amplitude of shear strain and the excitation frequency, and to analyze the correlation between viscoelasticity and energy absorption capacity. Secondly, the mechanical properties of STG modified by different particles were analyzed by doping inorganic particles. Finally, the nonlinear spring with damping and stiffness coordination is designed by using the improved STG. In this paper, the rheological properties of shear mode STG and the key problems of nonlinear spring are studied. It is of great significance to evaluate STG, understand the microstructure changes of STG and the application of STG. The main results of this paper are as follows: 1) the pure STG uses the large amplitude oscillatory shear (LAOS) experiment to define the linear and nonlinear regions of the material and to analyze the correlation between the viscoelastic energy and the energy absorption capacity. The analysis of strain scanning and its corresponding stress-strain curve shows that the shear strain amplitude of 2% is STG linear to nonlinear transition critical strain point. The critical conversion frequency is 7 Hz, and STG has excellent energy absorption in the liquid-solid transition region (2). The mechanical properties of STG are modified by inorganic particles (CaCO3 / SiCZO 2). The mechanical properties of the same particle with different mass fraction, the same mass fraction and different particle shear mode were tested, and the variation of modulus, loss factor, composite viscosity and the corresponding stress-strain curve were analyzed. The results show that CaCO_3 has a remarkable advantage in improving mechanical properties. 3) based on STG, the nonlinear spring with adaptive variable stiffness and variable damping is designed. The maximum stiffness of STG nonlinear spring under uniaxial compression test is 7 N / mmm. When the frequency is 10Hz, the maximum stiffness of STG nonlinear spring is 14 times higher than that under uniaxial compression. With the increase of frequency, the hysteresis loop becomes more and more full and has strong self-coordination. In order to better use STG in the field of shock absorption and protection, the linear and nonlinear definition of STG, the destruction of internal structure of STG in nonlinear region, should be avoided in engineering application. The design of STG nonlinear spring has good flexibility under the condition of slight vibration and good variable stiffness under the condition of violent vibration, which further promotes the practical development of STG.
【學(xué)位授予單位】：浙江工業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：O631.21

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 熊志遠(yuǎn);宋瑞祥;康鐘緒;劉磊;劉強(qiáng);;復(fù)合材料螺旋彈簧剛度及其影響因素分析[J];工程力學(xué);2015年09期

2 莊鵬;薛素鐸;劉雨冬;韓淼;;超彈性TiNi記憶合金螺旋彈簧的滯回性能實(shí)驗研究[J];功能材料;2015年13期

3 邵慧萍;趙子粉;鄭航;;亞微米級SiO_2微球?qū)棺矒舨牧霞羟性龀硪旱挠绊慬J];功能材料;2015年04期

4 劉東辰;曾京;池茂儒;高紅星;;空氣彈簧節(jié)流孔非線性力學(xué)模型研究[J];鐵道車輛;2014年12期

5 LIU Ying;ZHOU Kun;HUANG WeiFeng;GAO Zhi;WANG YuMing;;Numerical and experimental analysis of the reusability of spring energized metal C rings[J];Science China(Technological Sciences);2014年08期

6 甄亞林;李芾;霍芳霄;;空氣彈簧發(fā)展及其研究現(xiàn)狀[J];電力機(jī)車與城軌車輛;2014年01期

7 周鴻;郭朝陽;宗路航;宣守虎;龔興龍;;剪切增稠液及阻尼器性能研究[J];振動與沖擊;2013年18期

8 滕艷華;周晨;薛長國;;納米CaCO_3改性聚合物基復(fù)合材料研究進(jìn)展[J];化工時刊;2008年03期

9 范尚武;徐永東;張立同;成來飛;樓建軍;;C／SiC摩擦材料的制備及摩擦磨損性能[J];無機(jī)材料學(xué)報;2006年04期

10 伍秋美;阮建明;周忠誠;黃伯云;;SiO_2/聚乙二醇非牛頓流體流變性能研究[J];物理化學(xué)學(xué)報;2006年01期

相關(guān)博士學(xué)位論文 前2條

1 許陽光;新型磁敏智能軟材料（磁流變塑性體）的制備，表征及機(jī)理研究[D];中國科學(xué)技術(shù)大學(xué);2014年

2 徐鈺蕾;剪切增稠液的性能表征及其防護(hù)應(yīng)用研究[D];中國科學(xué)技術(shù)大學(xué);2012年

相關(guān)碩士學(xué)位論文 前1條

1 吳煥超;蒙脫土/橡膠納米復(fù)合材料結(jié)構(gòu)與性能的研究[D];大連理工大學(xué);2010年

，

本文編號：2150183