20CrMoH齿轮弯曲疲劳强度研究

发布时间：2018-01-12 18:16

本文关键词：20CrMoH齿轮弯曲疲劳强度研究　出处：《重庆大学》2011年硕士论文　论文类型：学位论文

【摘要】：20CrMoH渗碳齿轮由于加入了Mo元素而显著提高了材料的淬透性和心部硬度,因而具有较好的工艺性能和传动性能。这种齿轮广泛应用于中、重型汽车传动装置中。齿轮在工作过程中承受较大的载荷,齿轮的弯曲疲劳强度往往是其传动性能的关键技术指标。目前关于20CrMoH渗碳齿轮弯曲疲劳强度的研究尚未见报道。本文的研究主要包括以下几个方面: ①针对20CrMoH渗碳齿轮开展单齿弯曲疲劳强度试验。试验采用脉动加载法和成组试验方案,在电磁谐振疲劳试验机上对齿轮轮齿进行了5个应力级的疲劳强度试验。 ②依据平截面法和折截面法对不同载荷级下的齿根应力进行了计算,并对齿轮试样疲劳断口的宏观形貌进行了分析。 ③应用概率论与数理统计理论对试验数据进行对数正态分布、二参数威布尔分布和三参数三种概率分布类型的假设检验,分析定应力下20CrMoH渗碳齿轮弯曲疲劳寿命的概率分布形式。 ④对20CrMoH渗碳齿轮的弯曲疲劳寿命进行可靠性分析,拟合出该齿轮的P - S - N曲线以及不同可靠度下的弯曲疲劳极限应力。 ⑤结合APDL与齿廓方程,建立了20CrMoH渗碳齿轮参数化的有限元分析模型;基于ANSYS/FE—SAFE、以齿轮的计算齿根应力为基础,进行了齿轮弯曲疲劳强度分析,为齿轮弯曲疲劳强度研究提供了一种新的思路。
[Abstract]:20CrMoH carburized gear due to the addition of Mo element can significantly improve the hardenability of the material and the core hardness, which has good process performance and transmission performance. It is widely used in gear, heavy-duty automotive transmission. Gear bearing large load in the working process, the bending fatigue strength of gear is often the key technology the transmission performance index. The current research on bending fatigue strength of gear steel 20CrMoH has not been reported. This study mainly includes the following several aspects:
First, the single tooth bending fatigue strength test for 20CrMoH carburized gear is carried out. The pulsation loading method and group test scheme are adopted. 5 fatigue tests on the gear teeth are carried out on the electromagnetic resonance fatigue testing machine.
The stress of the tooth root under different load levels was calculated on the basis of the flat section method and the folded section method, and the macroscopic morphology of the fatigue fracture of the gear sample was analyzed.
(3) by applying probability theory and mathematical statistics theory, we test the probability distribution of bending fatigue life of 20CrMoH carburized gear under constant stress under lognormal distribution, two parameter Weibull distribution and three parameter three probability distribution type hypothesis test.
(4) reliability analysis of the bending fatigue life of 20CrMoH carburized gear, fitting the P S N curve of the gear and bending fatigue limit stress under different reliability.
The combination of APDL and tooth profile equation, establish the finite element analysis of 20CrMoH carburized gear parametric model; based on ANSYS/FE - SAFE, the calculation of tooth gear stress as the foundation, analyzed the bending fatigue strength of gear, provides a new way to study the bending fatigue strength of gear.

【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH132.41

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