發(fā)布時間：2018-05-12 05:22

  本文選題：GLARE層板 + 層間剪切性能��； 參考：《南京航空航天大學》2017年碩士論文

【摘要】：GLARE層板因其優(yōu)異的力學性能和減重效果,在飛機蒙皮等部位成功實現商業(yè)應用。GLARE層板由鋁合金薄板和復合材料交替鋪層熱壓固化而成,且鋪層具有可設計性,導致其界面體系復雜。層間抗剪切能力是該型層板重要的性能之一,但尚未有合適的測試方法能有效評價GLARE層板的層間剪切性能。本文研究GLARE層板短梁法(short-beam shear test method,SBS)層間剪切失效行為,分析不同失效模式的機理,探討合適的跨厚比(length-to-thickness,L/h)以使改進后的短梁法適用于GLARE層板層間剪切性能評價。同時,研究GLARE層板雙梁法(double short-beam shear test method,DBS)層間剪切失效行為,論證雙梁法用于GLARE層板層間剪切性能評價的可行性。本文對GLARE層板短梁法層間剪切失效行為與機理進行研究。制備了四種典型鋪層的3/2結構GLARE層板:GLARE 2A,GLARE 3,GLARE 4A和GLARE 6。研究了不同鋪層GLARE試樣在短梁法層間剪切試驗時不同跨厚比條件下的失效模式和力學行為,并對每種失效模式進行機理分析,探討適合該型層板層間剪切性能評價的跨厚比。本研究中所選的跨厚比范圍為5-12。研究結果表明,當跨厚比為8時,四種鋪層GLARE試樣都發(fā)生純剪切失效模式,即發(fā)生在中性層附近的層間脫粘分層,且表觀層間剪切強度值穩(wěn)定可靠,能有效表征GLARE層板的層間剪切性能。而跨厚比為5的短梁法層間剪切試驗獲得的是擠壓-剪切失效模式,且層間剪切強度值較大�？绾癖冗_到10或更大后,試樣發(fā)生了彎曲破壞,表觀層間剪切強度值降低。通過對不同模式的失效機理進行研究分析,證明跨厚比為8可用來評價GLARE-3/2層板層間剪切性能。同時,本文研究了GLARE層板雙梁法層間剪切的失效行為與機理,論證雙梁法用于該型層板層間剪切性能評價的可行性。自行設計了雙梁法的試驗夾具,夾具的精度和性能滿足試驗要求。具體研究了不同跨厚比條件下試樣的失效行為和失效機制。研究結果表明,由于雙梁法存在純剪切點,試樣在本文跨厚比(L/h=5-8)范圍內進行雙梁法層間剪切試驗都能發(fā)生有效的層間剪切失效。GLARE 2A和GLARE 6表現為中間鋁合金層與復合材料層之間的脫粘分層;GLARE 3的失效為90°復合材料層與中間鋁合金層之間的脫粘分層,以及90°復合材料層在壓頭處的局部開裂;GLARE 4A分層失效發(fā)生在0°復合材料層與中間鋁合金層之間,但90°復合材料層未有明顯破壞。在較小跨厚比時,試樣在中間支座和壓頭處有應力集中。此外,雙梁法剪切試驗獲得的表觀層間剪切強度值大于短梁法,但兩種方法之間不存在排它性。此外,為了研究GLARE層板層間剪切失效行為結構演變規(guī)律以及跨厚比的結構適用性,制備每種鋪層層板的4/3,5/4,6/5結構。研究結果表明,5/4和6/5的GLARE 3以及GLARE 4A在跨厚比為7時進行短梁法剪切試驗能發(fā)生有效的層間剪切失效。結構不影響GLARE 2A短梁法表觀層間剪切強度試驗值,而GLARE 3和GLARE 6的短梁法表觀層間剪切強度試驗值隨著層板厚度增加而降低。對于雙梁法,GLARE 2A層板隨著結構增厚層間剪切強度試驗值稍有下降,GLARE 3和GALRE 6同樣呈現下降趨勢。雙梁法和短梁法結構演變規(guī)律的一致性證明了短梁法跨厚比選取的合理性,以及雙梁法用于GLARE層板層間剪切性能評價的可行性。
[Abstract]:Because of its excellent mechanical properties and weight reduction effect, the commercial application of the GLARE laminates has been successfully achieved by the hot pressing of the alternating layer of aluminum alloy sheet and composite material in the surface of the aircraft, and the interface system is complex. The interlayer shear resistance is one of the most important properties of the type laminate, but it is still one of the most important properties of the laminates. No suitable testing method can effectively evaluate interlaminar shear properties of GLARE laminates. This paper studies the interlaminar shear failure behavior of the GLARE laminate short beam method (short-beam shear test method, SBS), analyzes the mechanism of different failure modes, and discusses the appropriate cross thickness ratio (length-to-thickness, L/h) to make the improved short beam method applicable to the GLARE laminar layer. The interlaminar shear failure behavior of GLARE laminates (double short-beam shear test method, DBS) is studied. The feasibility of using the double beam method to evaluate the interlaminar shear properties of GLARE laminates is demonstrated. In this paper, the interlayer shear failure behavior and mechanism of the GLARE laminate short beam method are studied. Four kinds of typical layer 3/2 are prepared. Structural GLARE laminate: GLARE 2A, GLARE 3, GLARE 4A and GLARE 6., the failure mode and mechanical behavior of different layer GLARE specimens under the condition of different cross thickness ratio in short beam interlaminar shear test are studied, and the mechanism analysis of each failure mode is carried out to discuss the cross thickness ratio suitable for the evaluation of interlaminar shear performance. The cross thickness ratio range of 5-12. shows that, when the cross thickness ratio is 8, the pure shear failure mode of the four layers of layers has a pure shear failure mode, that is, the interlayer debonding layer near the neutral layer, and the apparent shear strength of the apparent interlayer is stable and reliable, and the interlayer shear properties of the GLARE laminates can be effectively characterized. The interlayer shear test with the span thickness ratio of 5 is the short beam method. The compression shear failure mode was obtained, and the interlayer shear strength was larger. After the cross thickness ratio reached 10 or more, the specimen occurred bending failure and the apparent shear strength decreased. Through the study and analysis of the failure mechanism of different modes, it was proved that the cross thickness ratio of 8 could be used to evaluate the interlaminar shear properties of GLARE-3/2 laminates. In this paper, the failure behavior and mechanism of interlaminar shear between GLARE laminates and double beams are studied. The feasibility of the double beam method for interlaminar shear performance evaluation is demonstrated. A double beam test fixture is designed by ourselves. The accuracy and performance of the fixture meet the requirements of the test. The failure behavior and failure mechanism of the specimens under the conditions of different cross thickness ratio are studied. The results show that, due to the existence of the pure shear point in the double beam method, the effective interlaminar shear failure of the sample in the cross thickness ratio (L/h=5-8) of this paper can have effective interlaminar shear failure.GLARE 2A and GLARE 6 as the debonding layer between the intermediate aluminum alloy layer and the composite layer, and the failure of the GLARE 3 is 90 degree composite layer and medium. The debonding stratification between the aluminum alloy layers and the partial cracking of the 90 degree composite layer at the pressure head; the GLARE 4A stratification failure occurs between the 0 degree composite layer and the intermediate aluminum alloy layer, but the 90 degree composite layer has no obvious damage. The apparent interlayer shear strength obtained by the test is greater than the short beam method, but there is no exclusion between the two methods. In addition, in order to study the structure evolution law of the interlayer shear failure behavior of GLARE laminates and the structural applicability of the cross thickness ratio, the 4/3,5/4,6/5 structure of each layer plate is prepared. The results show that the GLARE 3 and GLARE of 5/4 and 6/5 are GLARE and GLARE. 4A can have effective interlayer shear failure in the short beam shear test when the cross thickness ratio is 7. The structure does not affect the apparent shear strength test value of the GLARE 2A short beam method, while the apparent shear strength test value of the short beam method of GLARE 3 and GLARE 6 decreases with the increase of the thickness of the laminar plate. To the double beam method, the GLARE 2A laminate is thickened with the structure. The test value of interlayer shear strength decreases slightly, the GLARE 3 and GALRE 6 also show a downward trend. The consistency of the structure evolution law of the double beam method and the short beam method proves the rationality of the selection of the short beam method and the feasibility of the double beam method for the evaluation of the interlaminar shear performance of the GLARE laminates.

【學位授予單位】：南京航空航天大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TB33

【參考文獻】

相關期刊論文 前3條

1 Hua-Guan Li;Juan Ling;Yi-Wei Xu;Zhong-Gang Sun;Hong-Bing Liu;Xing-Wei Zheng;Jie Tao;;Effect of Aging Treatment on Precipitation Behavior and Mechanical Properties of a Novel Aluminum Lithium Alloy[J];Acta Metallurgica Sinica(English Letters);2015年06期

2 蔣陵平;;Glare層板疲勞性能研究綜述[J];材料導報;2012年05期

3 馬宏毅;李小剛;李宏運;;玻璃纖維-鋁合金層板的拉伸和疲勞性能研究[J];材料工程;2006年07期

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本文編號：1877270