Sliding wear behavior of laser surface hardened austempered ductile iron
Sliding wear behavior of laser surface hardened austempered ductile iron
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DOI：
10.1016/j.jmrt.2020.10.050
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发表时间：
2020-11-01
影响因子：
6.4
通讯作者：
Qiu, Feng
中科院分区：
文献类型：
--
作者：
Han, Xue;Zhang, Zhenpu;Qiu, Feng
这项研究描述了激光表面硬化工艺对所产生的微观结构及其磨损行为的影响。球墨铸铁样品在三种不同的等温淬火温度下进行等温淬火：分别为232℃/288℃/398℃。然后，对每个样品进行激光表面硬化处理。设计了不同的激光间隙：1.5mm/3mm/4mm。使用光学显微镜观察微观结构，并使用 UMT-3 摩擦测试仪进行摩擦测试。使用洛氏硬度计测量热处理后的硬度。使用光学显微镜和扫描电镜观察磨损表面的不同微观结构及其分布。结果表明，激光加工产生莱氏体、马氏体或回火贝氏体显微组织。对这些微观结构进行维氏硬度测试。在激光间隙为 4 mm 的样品上观察到了原始的针状微观结构，而在激光间隙为 1.5 mm 或 3 mm 的样品上观察不到原始的针状微观结构。这是因为4毫米激光间隙的一部分超出了激光热影响区。一般来说，在回火贝氏体区观察到严重的犁耕磨损和涂抹磨损，但在贝氏体区观察不到。摩擦试验过程中会产生碎屑，导致三体磨料磨损，不仅导致磨损量增加，而且磨光了磨损表面。 (C) 2020 作者。由 Elsevier B.V. 出版
This study describes the laser surface hardening process effect on microstructures produced and their wear behavior. Ductile iron samples were austempered at three different austempering temperatures: 232 degrees C/288 degrees C/398 degrees C respectively. Then, the laser surface hardening process was applied on each sample. Different laser gaps were designed: 1.5mm/3mm/4 mm. The microstructures were observed using optical microscopy and tribo-tests were run using a UMT-3 tribo tester. A Rockwell hardness tester was used to measure the hardness after heat-treatment. Optical microscopy and SEM were used to observe the different microstructures and their distribution on the worn surface. The results showed that the laser processing generated ledeburite, martensite, or tempered bainite microstructures. Vickers hardness tests were carried out on these microstructures. The original needle-like microstructures were observed on the samples with 4 mm laser gap but not with 1.5 mm or 3 mm laser gap. This is because part of the 4 mm laser gap is beyond the laser heat effected zone. Generally, severe ploughing wear and smearing wear were observed on the tempered bainite zone but not the bainite zone. Debris was generated during the tribo-tests and led to three body abrasive wear which not only resulted in higher wear loss, but also polished the worn surface. (C) 2020 The Author(s). Published by Elsevier B.V.