Influence of Manufacturing Process and Alloying Element Content on the Tribomechanical Properties of Cobalt-Based Alloys
Influence of Manufacturing Process and Alloying Element Content on the Tribomechanical Properties of Cobalt-Based Alloys
复制标题
制造工艺和合金元素含量对钴基合金摩擦力学性能的影响
DOI：
10.1115/1.2991122
复制
发表时间：
2009
影响因子：
2.5
通讯作者：
S. Davies
中科院分区：
文献类型：
--
作者：
H. Yu;R. Ahmed;H. Lovelock;S. Davies
材料的制造工艺路线可以适应于操纵它们的微观结构，从而操纵它们的摩擦学性能。随着工业需求将摩擦材料的应用推向更高应力、缺乏润滑和改善寿命性能的更苛刻环境，可以定制制造工艺以优化其在特定工程应用中的使用。因此，本文的目的是了解耐磨钴基合金（司太立6）的粉末固结热等静压（HIP）和铸造两种不同的工艺路线生产的组织性能关系。该合金具有Co-28 Cr-4.5W-1C的标称重量%组成，其通常用于恶劣摩擦学环境中的磨损相关应用中。然而，铸造合金的粗大碳化物结构导致较高的脆性和较低的韧性。因此，本研究旨在了解通过改变热等静压工艺路线而引起的碳化物细化是否可以改善该合金的摩擦机械性能。微观结构和摩擦力学评价，其中涉及硬度，冲击韧性，磨料磨损，滑动磨损，和接触疲劳性能测试，表明，尽管两种合金的类似的磨料和滑动耐磨性，HIP合金表现出改善的接触疲劳和冲击韧性性能相比，铸造对应。这种行为的差异进行了讨论的结构-性能关系。这项研究的结果表明，HIPing工艺可以为该合金提供额外的抗冲击和疲劳性能，而不会影响硬度和耐磨性/滑动磨损性，这使得HIPed合金适合相对较高应力的应用。结果还与以前报道的调查的Stellite 20合金，其中有一个更高的碳化物含量相比，Stellite 6合金，所造成的合金元素的含量的变化。这些结果表明，抗疲劳性没有遵循冲击韧性改善的预期趋势。在设计过程中，硬度，韧性和碳化物含量的组合显示出复杂的相互依赖性，其中平均硬度降低40%和碳化物含量降低60%对接触疲劳抗力有更主导的影响相比，一个数量级的改善，在冲击韧性的HIPed Stellite 6合金。DOI：10.1115/1.2991122
Manufacturing process routes of materials can be adapted to manipulate their microstructure and hence their tribological performance. As industrial demands push the applications of tribological materials to harsher environments of higher stress, starved lubrication, and improved life performance, manufacturing processes can be tailored to optimize their use in particular engineering applications. The aim of this paper was therefore to comprehend the structure-property relationships of a wear resistant cobaltbased alloy (Stellite 6) produced from two different processing routes of powder consolidated hot isostatic pressing (HIPing) and casting. This alloy had a nominal wt % composition of Co–28Cr–4.5W–1C, which is commonly used in wear related applications in harsh tribological environments. However, the coarse carbide structure of the cast alloy results in higher brittleness and lower toughness. Hence this research was conducted to comprehend if carbide refinement, caused by changing the processing route to HIPing, could improve the tribomechanical performance of this alloy. Microstructural and tribomechanical evaluations, which involved hardness, impact toughness, abrasive wear, sliding wear, and contact fatigue performance tests, indicated that despite the similar abrasive and sliding wear resistance of both alloys, the HIPed alloy exhibited an improved contact fatigue and impact toughness performance in comparison to the cast counterpart. This difference in behavior is discussed in terms of the structure-property relationships. Results of this research indicated that the HIPing process could provide additional impact and fatigue resistance to this alloy without compromising the hardness and the abrasive/sliding wear resistance, which makes the HIPed alloy suitable for relatively higher stress applications. Results are also compared with a previously reported investigation of the Stellite 20 alloy, which had a much higher carbide content in comparison to the Stellite 6 alloy, caused by the variation in the content of alloying elements. These results indicated that the fatigue resistance did not follow the expected trend of the improvement in impact toughness. In terms of the design process, the combination of hardness, toughness, and carbide content show a complex interdependency, where a 40% reduction in the average hardness and 60% reduction in carbide content had a more dominating effect on the contact fatigue resistance when compared with an order of magnitude improvement in the impact toughness of the HIPed Stellite 6 alloy. DOI: 10.1115/1.2991122