论文标题
火热的火花和闪闪发光的斑点：磨损中的融化和球形粒子形成
Of fiery sparks & glittering spots: Melting-resolidification and spherical particle formation in abrasion
论文作者
论文摘要
当钢基材滑落到硬磨碎的情况下，罗伯特·胡克（Robert Hooke）首先在17 $^{th} $ Century中看到并记录在硬磨料上时，奇怪的是球形颗粒的奇怪出现。随后在许多其他磨蚀类型的过程中观察到了类似的颗粒，从钢的研磨到滑动岩石断层。最初由胡克提出的普遍假设是，这些颗粒是由于磨料和底物之间的局部温度而形成的，从而导致融化，液滴弹出和随后的溶解 - 融化 - 溶解假设假设。在这项工作中，我们使用\ emph {原位}分析模型钢质 - 浸泡接触几何形状进行了分析，并通过分析计算互补。发现在使用典型的接触条件下，接触区内的温度远非熔点，并且在没有氧气的情况下，球形颗粒不会形成。因此，我们提出了熔融固化假设的修改，涉及中间放热氧化阶段，并为过程的每个步骤提供定量证据。我们的结果对涉及球形金属颗粒的形成和利用的各种磨料系统具有影响
The curious occurrence of perfectly spherical particles when a steel substrate is slid against a hard abrasive was first observed and documented by Robert Hooke in the 17$^{th}$ century. Similar particles have subsequently been observed in numerous other abrasion-type processes, ranging from grinding of steels to sliding rock faults. The prevalent hypothesis, originally proposed by Hooke, is that these particles are formed due to high local temperatures between the abrasive and the substrate, resulting in melting, droplet ejection and subsequent resolidification -- the melting-resolidification hypothesis. In this work, we revisit this phenomenon using \emph{in situ} analysis of a model steel-abrasive contact geometry, complemented by analytical calculations. It is found that the temperature within the contact zone, for typical contact conditions used, is far from the melting point and that spherical particles do not form in the absence of oxygen. We thereby propose a modification of the melting-resolidification hypothesis, involving an intermediate exothermic oxidation stage, and provide quantitative evidence for each step of the process. Our results have implications for a wide class of abrasive systems that involve the formation and utilization of spherical metallic particles
