Deep cryogenic treatment (DCT) has been known since the 1930s to improve hardness, fatigue resistance, and wear resistance of steel. While the effect of DCT on wear properties has been well documented, there is no consensus regarding the causal mechanisms, nor a widely accepted quantitative description of them. DCT transforms retained austenite into martensite and triggers the precipitation of fine carbides, among other things. We observed that DCT had a negligible effect on Young's modulus and the yield limit of high carbon spring steel. The observed microstructural changes (presence of specific dendritic inhomogeneities typical for inclusions of austenitic phase in non-treated specimens and homogeneous microstructure of treated ones) can serve for qualitative purposes only. However, we found that DCT led to a decrease in steel electrical resistivity which can be explained by noticeable differences between the resistivities of the martensitic and austenitic phases. We propose a micromechanical model for electrical resistivity which allows monitoring of the content of retained austenite and postulate that it can be used for other materials as well. We also observed increased resistivity after mechanical loading of the specimens, correlating with increased dislocation density caused by loading. This quantity can be used to assess the average dislocation density.

自 1930 年代以来，人们就知道深冷处理 (DCT) 可以提高钢的硬度、抗疲劳性和耐磨性。虽然 DCT 对磨损性能的影响已被充分记录，但关于因果机制尚未达成共识，也没有广泛接受的定量描述。DCT 将残余奥氏体转变为马氏体，并引发细小碳化物的析出等。我们观察到 DCT 对高碳弹簧钢的杨氏模量和屈服极限的影响可以忽略不计。观察到的显微组织变化（未处理试样中奥氏体相夹杂物特有的特定枝晶不均匀性和处理试样的均匀微观结构的存在）仅可用于定性目的。然而，我们发现 DCT 导致钢电阻率降低，这可以通过马氏体相和奥氏体相电阻率之间的显着差异来解释。我们提出了一种电阻率微机械模型，它允许监测残余奥氏体的含量，并假设它也可用于其他材料。我们还观察到试样机械加载后电阻率增加，这与加载引起的位错密度增加有关。该数量可用于评估平均位错密度。我们提出了一种电阻率微机械模型，它允许监测残余奥氏体的含量，并假设它也可用于其他材料。我们还观察到试样机械加载后电阻率增加，这与加载引起的位错密度增加有关。该数量可用于评估平均位错密度。我们提出了一种电阻率微机械模型，它允许监测残余奥氏体的含量，并假设它也可用于其他材料。我们还观察到试样机械加载后电阻率增加，这与加载引起的位错密度增加有关。该数量可用于评估平均位错密度。