Influence of transformation toughening mechanisms of Zirconia based materials on the tribological performance under high mechanical contact loads and water lubrication

氧化锆基材料的相变增韧机制对高机械接触载荷和水润滑下摩擦学性能的影响

• 批准号: 233894750
• 负责人: Dr. Andreas Kailer
• 金额: --
• 依托单位: Forschungsbereich Mineralogie und Geodynamik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/233894750?language=en
• 关键词: Influence; transformation; toughening; mechanisms; Zirconia

Zirconia based materials are often used because of their combination of excellent wear resistance, high strength and toughness. Strength and toughness of zirconia are outstanding mechanical properties which make it the current standard ceramic material for pumps and seals. For these reasons, zirconia materials are often the first choice in applications with high mechanical loadings. In wet lubricated systems, however, the issue of low-temperature degradation during wear processes has to be investigated and become controllable in order to ensure a successful application over long periods of time. Thus, the proposed project aims for a basic clarification of a) mechanisms, kinetics and process parameters and b) the establishment of procedures to test degradation in situ aiming at the running-in phase of degradation for tribological development with respect to the interaction of degradation and wear.Model materials based on Y-doped tetragonal zirconia polycrystals (Y-TZP) and a composite material containing alumina (alumina toughened zirconia, ATZ) will be used to investigate the surficial phase transformation from tetragonal to monoclinic in wet lubricated systems as a function of environmental parameters (aqueous lubrication at temperatures between 20° and 90°C), loading conditions (speed, load, geometry) and time of treatment. The extent of trans-formation in amount and distribution is then correlated with microstructural changes (crack growth, residual stresses, and defects), resulting changes in mechanical properties (hardness, effective elasticity, toughness) and wear properties (friction, mass loss). An X-ray diffraction based in situ test and calibration procedure for the evaluation of critical conditions will be developed.

氧化锆基材料由于其优异的耐磨性、高强度和韧性的组合而经常被使用。氧化锆的强度和韧性是出色的机械性能，使其成为当前泵和密封件的标准陶瓷材料。由于这些原因，氧化锆材料通常是高机械负荷应用的首选。然而，在湿润滑系统中，必须研究磨损过程中的低温降解问题并使其可控，以确保长时间的成功应用。因此，拟议的项目旨在基本澄清a）机制、动力学和工艺参数，以及B）建立程序，以测试原位降解，目的是针对降解的磨合阶段，用于关于降解和磨损的相互作用的摩擦学开发。（氧化铝增韧氧化锆，ATZ）将用于研究在湿润滑系统中，作为环境参数（在20°和90°C之间的温度下的水性润滑）、载荷条件（速度、载荷、几何形状）和处理时间的函数，从四斜晶系到单斜晶系的表面活性剂相变。然后，数量和分布的转化程度与微观结构变化（裂纹生长、残余应力和缺陷）相关，从而导致机械性能（硬度、有效弹性、韧性）和磨损性能（摩擦、质量损失）的变化。将开发一种基于X射线衍射的现场测试和校准程序，用于评估临界条件。