摘要
汽车板簧常有使疲劳强度大幅度下降的脱碳层，而喷丸处理可以有效地改善其疲劳性能。目前用来表征板簧脱碳表面力学特性最常见的指标是Ｘ射线谱线的半高宽和显微硬度，该二参量不仅本身存在缺陷，而且二者给出的结果也不一致。采用Ｘ射线应力分析技术，可以获得金属表面的真实应力———应变关系，从而可以用表面屈服强度对板簧脱碳表面进行研究。采用逐级剥离方法可测得半高宽、显微硬度和表面屈服强度沿脱碳层深度的分布，测量结果表明，脱碳层严重软化，但上述３参量随层深的变化规律存在一定的差异。由于表面屈服强度直接反映材料抵抗塑性形变的能力，因此，表面屈服强度更能正确地表征材料力学特性的分布。
Spring steel of car has decarburized
layer which can decrease fatigue strength greatly, while shot peening disposal can effectively
improve its fatigue performance. Now the most common standards to charcterize the mechnical
property of a surface of spring steel decarburized layer are the half width of the X-ray and the
microhardness. The results given by them are quite different. Only by using X-ray stress
analysis techniques can we get the stress-strain relationship. So that we can characterize the
surface of spring steel decarburized layer by using yield strength and then study it. We can
measure the half width, microhardness and the yield strength on each layer of the decarburized
layer by adopting the peeling-off method, the results show that the decarburized layer softens
greatly. The above three parameters in the shot peening affected layer of a decarburized
sample were different from each other. Bacause yield strength can directly reflect the material
capability of resisting plastic deformation, it may be believed that this parameter can
characterize the mechanical property of a surface or a surface layer more correctly.
出处
《石油化工高等学校学报》
CAS
1999年第2期60-62,共3页
Journal of Petrochemical Universities
基金
国家自然科学基金
