[图像上图]复制研究已经证明了方法学的轻微变化如何显着影响结果。确定这种看似较小的因素可以帮助研究人员进行更准确的复制。信用：Pixabay
I remember reading many news articles in the early- to mid-2010s on the “replication crisis” in science. This “crisis” was sparked by the publication of some high-profile papers that found a large percentage of results in published research articles across different disciplines (especially the social sciences) could not be reproduced.
While some news organizations were quick to claim these findings as evidence that science was failing, researchers swiftly stepped up to defend the scientific process and point out that in many cases these replication studies simply revealed challenges already known to scientists when it comes to conducting experiments.
For example, researchers have shown that studies deemed contextually sensitive are harder to reproduce because the original study’s exact circumstances can be difficult or impossible to replicate. As New York University associate professor of psychology Jay Van Bavelwrites in纽约时报, “Imagine a study that examined whether an advertisement for a ‘colorblind work environment’ was reassuring or threatening to African-Americans. We assumed it would make a difference if the study was conducted in, say, Birmingham, Ala., in the 1960s or Atlanta in the 2000s.”
此外，方法论的轻微变化会显着影响结果。我曾经读过两个研究小组试图执行同一实验的研究小组的轶事。他们花了几个月的时间来确定其不同结果的原因 - 一组使用磁性搅拌棒搅动溶液，而另一组则用手旋转烧瓶。
For many researchers, then, this “replication crisis” is not so much a crisis as it is an indicator of how to further improve research practices.
在论文中提供更详细的方法是一种可以帮助提高可重复性的做法。正如上面搅拌的轶事所示，实验条件的最小变化有时会对结果产生巨大影响。因此，提供有关实验设置的详细说明，并了解看似较小的方法论变化如何影响实验 - 使研究人员进行准确的复制。
In a最近的研究出版于材料信，来自墨西哥国家理工学院和TecnológicoDeMonterrey的研究人员研究了一种看似较小的方法论变化对实验的影响，这是在SCRATCH测试中使用的凹痕尖端的半径。
刮擦测试是一种用于测试薄膜和硬涂层的粘附强度的常见方法。该测试涉及在涂层样品上逐渐增加缩进载荷，该样品以恒定速度移动，直到沿刮擦凹槽鉴定出故障机构。观察到明确的故障机制的负载称为临界负载。
Researchers have evaluated the effect of indenter tip radius on the critical loads of various coating and substrate combinations, for example,这里和这里. However, despite the variety of these studies, “there is no information focusing on adhesion strength analysis of a coating/substrate system developed by a thermochemical diffusion process such as nitriding, cementing or more precisely, boriding,” the researchers write.
So, they investigated the effect that indenter tip radius has on critical loads of borided materials, specifically double phase boride layers (FeB/Fe2B) on AISI H13 steel, which is a tool steel grade standardized for hot working.
The researchers used a diamond Rockwell-C indenter tip for the scratch adhesion tests. Initial loads of 1, 2.5, 5, and 10 N and final loads of 10, 25, 50, and 100 N were selected for indenter tip radiuses of 20, 50, 100, and 200 μm, respectively.
扫描电子显微镜分析表明，硼钢中的主要破坏机制是横向开裂，碎裂和碎屑。虽然20μm的凹痕尖端半径在硼表面上产生了更严重的损伤，但较严重的底物塑性变形发生在200μm的凹痕尖端半径上。因此，总体而言，“较小的凹痕尖端半径会造成更严重的损坏”。
The paper, published in材料信, is “Scratch test in boride layers: influence of indenter tip radius on failure mechanisms”（doi：10.1016/j.matlet.2022.131918）。