High temperature (900 °C) sliding wear of CrNiAlCY coatings deposited by high velocity oxy fuel thermal spray
High temperature (900 °C) sliding wear of CrNiAlCY coatings deposited by high velocity oxy fuel thermal spray
复制标题
高速氧燃料热喷涂CrNiAlCY涂层的高温（900℃）滑动磨损
DOI：
10.1016/j.surfcoat.2021.128063
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发表时间：
2022
影响因子：
5.4
通讯作者：
Derelizade K
中科院分区：
文献类型：
--
作者：
Derelizade K
镍基高温合金是高温应用的理想材料，其耐腐蚀、耐冲蚀和耐磨损性能一直是人们研究的重点。镍铬（NiCr）合金广泛用于耐腐蚀涂层，而碳化铬镍铬（CrC-NiCr）合金优选用于高温下的耐磨涂层。在这项研究中，CrNiAlCY涂层沉积通过液体燃料的高速氧燃料（HVOF）热喷涂使用两个喷涂参数和耐磨涂层测试。研究了工艺参数对涂层组织和力学性能的影响。结果表明，较高的氧气流量是获得具有较低孔隙率和较高的显微硬度的涂层的关键。选择具有较低孔隙率和较高硬度的涂层用于在球盘设置中的室温（~24 °C）和高温（900 °C）无润滑滑动磨损测试。在3种不同载荷条件（10、30和60 N）下，对涂层与氧化铝配对体进行测试。在室温下，涂层的磨损率与所施加的载荷成正比。在室温测试中，产生磨损碎屑，然后氧化并推到磨损痕迹的边缘。另一方面，在高温试验中，磨损碎屑被涂抹在磨损表面上。表面在高温下被氧化成Cr2 O3，其充当保护层。虽然在较高温度下发生热软化，但由于在顶面上形成保护性氧化层，在10和30 N下的磨损率与室温值相似;然而，在60 N下的氧化层不能承受载荷，开始开裂并失去保护能力。
Nickel based superalloy are in demand for high temperature applications and their corrosion, erosion and wear resistance have been investigated for a long time. Nickel chromium (NiCr) alloys are widely used for corrosion resistant coatings, while chromium carbide nickel chromium (CrC-NiCr) alloys are preferred for wear resistant coatings at high temperature. In this study CrNiAlCY coatings were deposited via a liquid fuelled high velocity oxy fuel (HVOF) thermal spray using two spray parameters and tested as wear resistant coatings. Effects of processing parameters on microstructure and mechanical properties of the coatings were investigated. Results showed that higher oxygen flow rates are critical for obtaining coatings with lower porosity and higher microhardness. Coating with lower porosity and higher hardness was chosen for both room temperature (~24 °C) and high temperature (900 °C) unlubricated sliding wear tests in a ball on disc setup. The coating was tested against alumina counterbody under 3 different loading conditions (10, 30 and 60 N). The wear rate of the coating was directly proportional to the applied load at room temperature. In the room temperature tests, wear debris was produced, which then oxidised and pushed away to the edges of the wear track. On the other hand, wear debris was smeared on the wear surface at high temperature tests. The surface was oxidised into Cr2O3at high temperatures, which acted as a protective layer. Although thermal softening took place at higher temperatures, wear rates under 10 and 30 N were similar to room temperature values due to the protective oxide layer formed on the top surface; however, the oxide layer under 60 N could not withstand the load, started to crack and lost its protective ability.