The effect of supper rapid induction quenching to fatigue property of steel

超快速感应淬火对钢疲劳性能的影响

基本信息

批准号：
08555027
负责人：
SHIMIZU Masao
金额：
$ 1.09万
依托单位：
KEIO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

In this study, for the purpose of making clear the fatigue property of surface hardened steel by super rapid induction quenching, measurement of hardness, residual stress and fatique test on plane and notched specimen consisted of 0.45 C steel given hardening layr by super repid quenching were carried out.Significant ant remarkable results were obtained. The summary of those results is as below.1. A high compressive residual stress (more than-1000MPa on plane specimen and-3000MPa on notched specimen) was observed on the surface of specimen and easy control of hardening depth has become possible. As a results of a fatigue strength of those quenched specimen became higher compared with non-quenched specimen. Especially, fatigue strength of notched specimen with 1.0mm depth hardening layr was over 2000MPa.2. These exists a residual concentration at a notch root which is similar to an ordinary stress concentration at the notch root in the specimen subjected to an axial loading. The degree of a residual stress concentration depends on the notch sharpness.3. The release of residual stress occurs in the fatigue process of super rapid induction hardened steel depending on the magnitude of stress amplitude. At a higher stress amplitude, the release of a residual stress becomes more remarkable.4. High compresive residual stress has an effect of restraining the separation of the non-metallic inclusion from surrounding steel. This means that a high residual compressive stress can suppress a fatigue from an inclusion which results in the fatigue fracture with a fish eye pattern.

在这项研究中，为了清除表面硬化钢的疲劳特性，通过超快速诱导淬火，对平面和缺口样本上的硬度测量，残留应力和FATIQUE测试，由超级恢复的淬灭进行硬化液体组成的0.45 c钢。这些结果的摘要如下1。在样品表面上观察到了高压缩的残留应力（在平面样品上超过1000MPa，在凹口样品上的3000MPA）已成为可能。与未猝灭标本相比，这些淬火标本的疲劳强度的结果变得更高。尤其是，具有1.0mm深度硬化layr的缺口标本的疲劳强度超过2000mpa.2。这些存在于缺口根部的残留浓度，该浓度与经受轴向载荷的样品中的Notch根部的普通应力浓度相似。残留应力浓度的程度取决于缺口清晰度。3。残留应力的释放发生在超快速诱导硬化钢的疲劳过程中，具体取决于应力振幅的幅度。在更高的应力振幅下，残余应力的释放变得更加显着。4。高兼容的残余应力具有限制非金属包容性与周围钢的分离的作用。这意味着高残余压力应抑制纳入中的疲劳，从而导致鱼眼的疲劳骨折。