The evolution of the subsurface zone formed during the dry sliding in OFHC copper samples was traced using the positron annihilation technique. As the sliding distance increases the total range of the subsurface zone increases and a tribolayer thickness of about 20 μm appears. This layer contains fine grains with high angle grain boundaries, which indicates continuous dynamic recrystallization proceeds there. Below is a layer of larger grains, but at their boundaries, there are placed fine grains formed by the discontinuous dynamic recrystallization process. Both layers are well recognized by the depth dependencies of the mean positron lifetime but also are observed directly in electron backscattering diffraction images. A temperature close to the melting point of approx. 900 °C is needed to recover and rebuild the microstructure and heat almost all defects of the tribolayer, while for layers located much deeper, a much lower temperature is sufficient. No tribolayer was observed in the copper sample exposed to the sliding test with the oil lubricant with MoS₂ particles, even at a very long sliding distance. This is reflected in a significant reduction in the wear rate of such a sample compared to a sample exposed to the dry sliding test.

使用正电子湮没技术追踪在 OFHC 铜样品中干滑动期间形成的地下区域的演变。随着滑动距离的增加，次表面区域的总范围增加，并且出现约 20 μm 的摩擦层厚度。该层包含具有大角度晶界的细晶粒，这表明在那里进行连续动态再结晶。下面是一层较大的晶粒，但在它们的边界处，放置了由不连续动态再结晶过程形成的细晶粒。通过平均正电子寿命的深度依赖性可以很好地识别这两层，但也可以直接在电子背散射衍射图像中观察到。接近熔点的温度约。需要 900 °C 来恢复和重建微观结构并加热摩擦层的几乎所有缺陷，而对于更深的层，低得多的温度就足够了。在使用含 MoS 的油润滑剂进行滑动测试的铜样品中未观察到摩擦层_{2 个}粒子，即使在很长的滑动距离下。这反映在与暴露于干滑动测试的样品相比，这种样品的磨损率显着降低。