【作者】 邱岩；

【导师】 包亦望； Stephen J.Bennison；

【作者基本信息】 中国建筑材料科学研究总院 ， 材料学， 2008， 博士

【摘要】 在玻璃及其层合材料的性能评价领域,常常会遇到常规实验技术和仪器都难以实现的问题,如玻璃材料的残余应力及其均匀性评价、钢化玻璃的自爆风险、表面缺陷的损伤演变等。因此探索新的评价技术和测试仪器是国内外材料科学家和力学工作者的紧迫而重要的任务。也是保障脆性材料工程应用的关键。本论文围绕玻璃和玻璃复合材料的性能评价和仪器研发开展一些工作。首先基于模块化设计思想,开发设计了脆性材料表面性能试验仪,其主要包括加载模块、支撑平台、控制模块、软件模块和功能模块等模块,利用模块之间的不同配合实现立式、卧式、现场吸盘、局部加载四种试验模式,可以满足不同的试验需求;试验仪具有测试脆性材料常规力学性能的功能外,还可以配合声发射模块捕捉玻璃材料局部强度,对玻璃构件进行强度保证试验;提高玻璃构件使用的安全可靠性。同时为了得到玻璃材料与不同摩擦副的摩擦系数,开发了与表面试验仪配套摩擦磨损测试装置及其实验软件。利用球压法非破坏性地测试玻璃和钢化玻璃的局部强度和残余应力,并利用声发射压头确定裂纹起始的临界载荷。实现了强度的非破坏性测试;采用“十字交叉法”实验装置对层合材料和夹层玻璃的界面拉伸和界面剪切强度进行评价分析,证明这是一种简便精确的界面强度测试方法。以该测试装置立式工作模式作为工作平台,考察了不同载荷下钠钙硅玻璃与45钢对磨时的摩擦磨损性能,并利用双环实验测试了不同加载时间的钠钙硅玻璃残余强度,探讨了材料的磨损机理。磨损率随着载荷的增加出现波动,当载荷低于10N时,摩擦系数随载荷增加而明显增大,而当载荷超过10N时,摩擦系数随载荷增加而明显降低,在较低载荷下,钠钙硅玻璃的磨损失效主要源于轻微点蚀,在较高载荷下,其磨损失效主要源于表层塑性变形。通过分析脆性材料裂纹扩展的均强度准则和颗粒周边应力分布,证明了玻璃的裂纹扩展受应力作用的空间和时间的影响,即裂纹应力峰值随应力梯度增加而增加,同时也随应力作用的时间减小而增加。并由此分析了引起钢化玻璃自爆的杂质的临界尺寸约为0.2mm。研究表明,玻璃表面钢化应力越大,强度整体越高,但是同时自爆概率也越大。通过有限元分析方法与三点弯曲、球-环弯曲方法研究了牙用玻璃-氧化铝复合材料的残余应力与破坏机制。在多功能材料表面试验仪上用小双层盘状样品进行了轴对称的测试。结果表明层间的热膨胀系数差异导致了其间的残余应力,并且应力的分布与厚度比例和温度差有关。结合国家863项目和重大国际合作项目,完成多台实验仪器的研发,主要创新点是模块化、多功能、和智能化,并将声发射技术、位移敏感压痕技术、图像监测和常规万能材料试验机的基本功能结合为一体。实现了玻璃及其复合材料的各种表面与界面性能的简单方便检测。更多还原

【Abstract】 In the field of property evaluation of glass and the glass lamination material, there are lots of questions that are difficult to solve by using the conventional experimental techniques and the instruments, such as the estimation of the residual stress and the uniformity of the glass materials, the spontaneous breakage risk of tempered glass, damage evolution of the surface defect, and so on. Therefore, it was the urgent and vital duty of material scientists and mechanical workers to explore new testing technique and instruments, which was also the key to assure the application of brittle materials in engineering. This work focuses on the property evaluation and the equipments development of the glass and the glass composites.Based on the modularization design, a testing machine for surface and interface properties was developed and designed which mainly include the loading system, the supporting platform, the control system, the software module and the functional module, and so on. Four kind of experimental models, namely, vertical type, horizontal type, in-site sucker, local–loading could be realized using the different coordination between the modules which could meet the different experimental need. The tester could test not only the convention mechanical properties of brittle materials, but also the local strength of glass materials and the proof test of the glass component by combining acoustic emission module to improve the reliability of the glass component in service. Simultaneously, the friction and wear testing device and software which supported the surface tester was developed to obtain the friction coefficients of glass materials to different materials.Spherical-indentation method was used for non-destructive test of the local strength and residual stress of the glass and tempered glass. And the critical cracking load was determined using indenter containing acoustic emission sensor which was successful in non-destructive testing strength. "Cross-sample" experimental device was proven as a simple and accurate testing method for evaluation and analysis of the interface tensile and shear strength of laminated materials and laminated glass.Vertical working pattern of the device being as the working platform, the friction and wear properties of the soda-lime glass abrasion with 45 steel was investigated under the different load. And the residual strength of the soda-lime glass samples after the wear tests were measured with double-ring tests. It was indicated that the rate of wear fluctuates with the increasing normal pressure. The friction coefficient increased largely with the increase of load when the load was lower than 10N. The wear-out failure of the soda-lime glass resulted mainly from the spot corrosion under the low load whereas it was from the surface plastic deformation under the high load. Through the analysis in Mean-stress criterion of the crack growth of brittle material and the stress distribution of particle, it was proven that crack growth of glass was influenced by the space and the time of applied stress, i.e., the peak value of cracking stress increases with the increasing of stress gradient, and with the decreasing of stressing time. According to this analysis, it was predicted that the critical size of impurity which caused the spontaneous breakage in tempered glass was approximately 0.2 mm. The research indicated that the residual stress in the tempered glass make the bending strength higher, but also make the probability of the spontaneous breakage higher.The residual stress and failure mechanism of the glass-alumina laminated materials for teeth were studied through the finite element method and three-spot bending tests, and ball-on -ring tests. The axial symmetry test was carried out with the small bi-layer disc sample using the self-made mini-tester. The result indicated that thermal coefficient of expansion between layers resulted in the residual stress. Meanwhile the stress distribution was related to the thickness ratio and the temperature difference.Based on the national 863 projects and the international cooperation projects, many test instruments were successfully devised. The main innovations of these instruments laid in modulation, multi-function, intellectualization, and they also integrated the fundamental function of the acoustic emission, depth-sensing indentation、visual monitoring and general universal material testing machine. The study provides a simple and convenient way and equipment to test the surface properties and interfacial behavior of the glass and laminated galss.更多还原