权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on Residual Stress and Load Bearing Capacity of Induction Hardened Gears

感应淬火齿轮残余应力及承载能力研究

基本信息

批准号：
03650129
负责人：
ODA Satoshi
金额：
$ 1.41万
依托单位：
Tottori University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1993
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03650129/
关键词：
Gear Induction Hardening Residual Stress Bending Fatigue Strength Surface Durability Electromagnetic Field Analysis Heat Conduction Analysis Elastic-Plastic Stress Analysis 歯面強度

项目摘要

Eddy current distribution and amount of heat originated from induction heating of a circular bar were caculated by means of FEM electromagnetic field analysis method, and the validity of this FEM program was confirmed by comparing the results by the FEM with those by the theoretical equatin. An electromagnetic fied analysis, a heat conduction analysis and an elastic-plastic stress analysis of the shafts during induction heating and water cooling processes with uniform cross-section and with semicircular notch were carried out by the FEM, considering changes of the magnetic ermeability, the resistivity, the thermal expansion coefficient and the yield stress with the temperature. The effects f the electric pwer, the frequency, the heating time, the diameter and the notch on the residual stress of the shaft were examined.A heat conduction analysis and an elastic-plastic stress analysis in case-hardening process of the thin-rimmed spur gear were carried out by the FEM, considering changes … More of the thermal expansion coefficient and the yield stress with the temperature and the carbon content distribution. The effects of the case depth, the parts (tooth and/or bore) of hardening, the rim thickness and the standard pressure angle on the residual stress of the gear were examined.The main results obtained from this investigation are summarized as follows.1. In the induction hardening process of the shaft, the time t_h taken for the surface temperature to reach the hardening teperature decreases with increasing electric power and frequency, and the temperature difference T_s-T_c between the surface and the center of the shaft increases. The time t_h increases with increasing diameter of shaft and the temperature difference T_s-T_c decreases. 2. There is an optimum induction hardening condition (electric power, frequency and heating time) for the residua stress of the ahaft due to induction hardening. 3. The axial residual stress sigma_z near the notch bottom of the shaft with semicircular notch due to induction hardening is fairly small compared with that of the straight part for short heating time, but approaches to sigma_z of the straight part with increasing heating time. 4. Residual stress at Hofer's critical section of the spur gear due to case-hardening decreases with rim thickness and increases with standard pressure angle (20ﾟ(〕SY.ltoreq.〔)alpha_0(〕SY.ltoreq.〔)27ﾟ). There is an optimum case depth for residual stress of the spur gear due t case-hardening. Less

采用有限元电磁场分析方法计算了圆棒感应加热时的涡流分布和发热量，并将计算结果与理论公式计算结果进行了比较，验证了有限元程序的正确性。采用有限元法对等截面半圆形缺口轴进行了感应加热水冷过程的电磁场分析、热传导分析和弹塑性应力分析，考虑了磁导率、电阻率、热膨胀系数和屈服应力随温度的变化。研究了电功率、频率、加热时间、直径和切口对轴残余应力的影响;采用有限元法对薄壁直齿圆柱齿轮表面淬火过程进行了热传导分析和弹塑性应力分析 ...更多信息热膨胀系数和屈服应力随温度和碳含量分布的变化规律。研究了齿轮表面硬化层深度、硬化部位（轮齿和/或孔）、轮缘厚度和标准压力角对齿轮残余应力的影响，主要结果如下.在轴的感应淬火过程中，随着电功率和频率的增加，表面温度达到淬火温度所需的时间th减小，表面与中心的温差Ts-Tc增大。随着轴径的增大，时间th增大，温差Ts-Tc减小。2.感应淬火残余应力存在一个最佳的淬火条件（功率、频率和加热时间）。3.在短时间加热条件下，半圆形缺口轴的缺口底部附近的轴向残余应力σ z与直段的轴向残余应力σ z相比较小，但随着加热时间的延长，轴的缺口底部附近的轴向残余应力σ z逐渐接近直段的σ z。4.由于表面硬化，在正齿轮的霍费尔临界截面处的残余应力随着轮缘厚度而减小，并且随着标准压力角（20 ° SY ≤）而增大。（）alpha_0（）SY ≤()27）。直齿圆柱齿轮表面淬火残余应力存在一个最佳硬化层深度。少