Evaluation Reliability of Hybrid Surface Modification Material by Carburizing and Fine Particle Peening

渗碳和细颗粒喷丸混合表面改性材料的可靠性评价

基本信息

批准号：
10650103
负责人：
EGAMI Noboru
金额：
$ 1.66万
依托单位：
Meijo University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650103/
关键词：
Hybrid Surface Modification Fine Particle Peening Fatigue S-N Cueve Crack initiation Life Mechanical Properties Diffraction Pattern of Product Fracture Mechanics 表面改賃複合処理浸炭窒化残留応力疲労強度応力拡大係数幅浸炭処理疲労き裂圧縮残留応力

项目摘要

(1)This study examines the effect of hybrid surface modification by vacuum carburizing and fine particle peening on fatigue strength behaviors of SCM415 material. We used quenched, vacuum carburized and hybrid, vacuum carburized and fine particle peened, specimen made of SCM415 and measured their hardness distribution, mechanical properties, fatigue strength and crack propagation. In terms of the fatigue behaviors, we investigated the relationship between the crack propagation rate da/dN and stress intensity factor range ΔK, da/dN and effective stress intensity factor range ΔKeff, as well as the fatigue crack initiation life N_i and crack failure life N_f of specimens. The results show specimens with hybrid surface modification are effective in the prevention of fatigue crack initiation and fatigue crack propagation.(2)This study examines numerical analysis of particle velocity and temperature distribution of struck material surface in fine particle peening. When the particle is accelerated using a direct-pressure type, the velocity of a 50μm particle, just before striking the metal surface, was calculated to be 222m/s. In applying air pressure, the acceleration of fine particles show significant increase compared to larger sizes. Moreover, the experimental values agree well with the calculated ones. On the other hand, the temperature distributions show the maximum surface temperature to be 1000K and cools instantly.

(1)本研究研究了真空渗碳和细颗粒喷丸混合表面改性对SCM415材料疲劳强度行为的影响，我们使用了淬火、真空渗碳和混合、真空渗碳和细颗粒喷丸，并测量了由SCM415制成的样品。硬度分布、力学性能、疲劳强度和裂纹扩展在疲劳行为方面，我们研究了裂纹扩展速率 da/dN 与应力强度因子范围之间的关系。 ΔK、da/dN和有效应力强度因子范围ΔKeff，以及试件的疲劳裂纹萌生寿命N_i和裂纹失效寿命N_f结果表明，混合表面改性的试件能够有效地防止疲劳裂纹萌生和疲劳裂纹。 (2)本研究对细颗粒喷丸中的颗粒速度和撞击材料表面的温度分布进行了数值分析。当使用直接压力类型加速颗粒时，50μm颗粒的速度，就在之前。计算得出，在施加气压时，细颗粒的加速度与较大尺寸的颗粒相比显着增加，而且实验值与计算值非常吻合。温度分布显示最高表面温度为1000K并立即冷却。