钼纤维增强树脂矿物复合材料机理研究

发布时间：2018-07-15 22:21

【摘要】：研究开发性能优越的新型机床基础件材料是改善和提高机床综合性能的有效手段之一。树脂矿物复合材料亦称为人造石,其突出优点是阻尼性能好,为普通灰铸铁材料的10倍左右,适用于制造高速和精密加工机床等设备的基础件,能够满足机床高速、精密和高热稳定性要求。本文针对树脂矿物复合材料力学性能较差的缺点,研究采用高强度的钼纤维提高其力学性能。旧钼纤维为电火花线切割加工报废的钼丝材料,其表面上随机分布着大量的放电凹坑。建立了钼纤维增强树脂矿物复合材料的物理模型,分析其界面作用机理,得到钼纤维与树脂基体的界面结合方式。树脂基体和旧钼纤维之间通过机械锁结、液体对固体表面的浸润以及原子或分子间的相互扩散建立界面结合；新钼纤维表面光滑,产生的机械锁结现象可以忽略,其界面结合主要是通过液体对固体表面的浸润和原子或分子间的相互扩散。新旧钼纤维的拉伸性能测试结果表明,旧钼纤维的塑性变形阶段很短,基本上不产生塑性应变,更适合用于增强树脂矿物复合材料。建立了分析钼纤维与树脂基体界面结合强度与界面滑移阻力的有限元模型,分析结果表明旧钼纤维限制复合材料受力变形和承担荷载量的能力均强于新钼纤维。当界面的滑移阻力小于钼纤维的抗拉强度极限时,钼纤维增强树脂矿物复合材料承受的最大荷载与放电凹坑的数量成正比。与新钼纤维相比,旧钼纤维与树脂基体的界面滑移阻力更大,在脱粘面上可以承受更多的荷载,能够起到更好的增强作用。试验研究了新旧钼纤维增强树脂矿物复合材料的抗弯强度与抗压强度,结果表明：新旧钼纤维都能起到增强效果,并且旧钼纤维的增强效果更好,成本更低。其中,新钼纤维增强树脂矿物复合材料的抗压强度提高4.9%,抗弯强度提高22.6%；旧钼纤维增强树脂矿物复合材料的抗压强度提高12.7%,抗弯强度提高32.5%。研究了直线形钼纤维与异形钼纤维对树脂矿物复合材料的增强机理,建立异形钼纤维的拉拔模型,给出了四种异形钼纤维最大拉拔力的表达式,在弯曲变形角相同、应力集中影响较小的条件下,四种异形钼纤维的最大拉拔力由大到小的顺序为：W形U形N形V形。对四种异形铝纤维增强树脂矿物复合材料分别进行了抗弯强度和抗压强度测试,结果表明：异形钼纤维对树脂矿物复合材料力学性能的增强效果均优于直线形钼纤维,并且W形钼纤维的增强效果最好,与理论分析结果基本一致。
[Abstract]:It is one of the effective ways to improve and improve the comprehensive performance of machine tools by researching and developing new machine tool base materials with superior performance. Resin mineral composite is also called artificial stone. Its outstanding advantage is that it has good damping property and is about 10 times as high as ordinary gray cast iron. It is suitable for manufacturing the basic parts of equipment such as high speed and precision machining machine tools, and can satisfy the high speed of machine tools. Precision and high thermal stability requirements. Aiming at the disadvantage of poor mechanical properties of resin mineral composites, the high strength molybdenum fiber was used to improve its mechanical properties. The old molybdenum fiber is an abandoned molybdenum wire material in WEDM, and a large number of discharge pits are distributed randomly on the surface. The physical model of molybdenum fiber reinforced resin mineral composite was established, and the interfacial mechanism of molybdenum fiber reinforced resin mineral composite was analyzed, and the interfacial bonding mode between molybdenum fiber and resin matrix was obtained. The interfacial bonding between the resin matrix and the old molybdenum fiber is established by mechanical locking, the soakage of the liquid to the solid surface and the diffusion of atoms or molecules; the surface of the new molybdenum fiber is smooth and the mechanical locking phenomenon can be neglected. The interfacial bonding is mainly through the infiltration of liquid to the solid surface and the diffusion of atoms or molecules. The test results of tensile properties of new and old molybdenum fibers show that the plastic deformation stage of old and old molybdenum fibers is very short and there is no plastic strain, so it is more suitable for reinforcing resin mineral composites. A finite element model for the analysis of interfacial bond strength and interfacial slip resistance between molybdenum fiber and resin matrix is established. The results show that the old molybdenum fiber is better than new molybdenum fiber in limiting the mechanical deformation and bearing load of the composite. When the slip resistance of the interface is smaller than the tensile strength limit of the molybdenum fiber, the maximum load of the molybdenum fiber reinforced resin mineral composite is directly proportional to the number of discharge pits. Compared with the new molybdenum fiber, the interfacial slip resistance between the old molybdenum fiber and the resin matrix is greater, and it can bear more loads on the debonding surface and play a better strengthening role. The flexural strength and compressive strength of the new and old molybdenum fiber reinforced resin mineral composites were studied. The results show that the new and old molybdenum fibers can play a reinforcing effect, and the reinforcement effect of the old molybdenum fiber is better and the cost is lower. Among them, the compressive strength and flexural strength of new molybdenum fiber reinforced resin mineral composites were increased by 4.9 and 22.6respectively, and the compressive strength and flexural strength of old molybdenum fiber reinforced resin mineral composites were increased by 12.7and 32.5, respectively. The reinforcement mechanism of linear molybdenum fiber and special-shaped molybdenum fiber on resin mineral composite was studied. The drawing model of special-shaped molybdenum fiber was established. The expression of the maximum drawing force of four special-shaped molybdenum fibers was given, and the bending deformation angle was the same. When the stress concentration is small, the order of the maximum drawing force of the four molybdenum fibers is: W shape U shape N shape V shape. The flexural strength and compressive strength of four kinds of special-shaped aluminum fiber reinforced resin mineral composites were tested. The results showed that the reinforcement effect of special-shaped molybdenum fiber on the mechanical properties of resin mineral composite was better than that of linear molybdenum fiber. The W-shaped molybdenum fiber has the best reinforcing effect, which is consistent with the theoretical analysis.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TH145.9;TB332

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