基于应力测试对某车型耐久后钣金开裂问题的分析与研究

应力测试是汽车行业常用的疲劳寿命分析手法,当车身零件发生焊点开裂等疲劳破坏问题时,在应力集中位置贴伏应变片,然后在特定的恶路进行应力测试,采集应力数据,结合材料的疲劳限度及S-N曲线,通过分析应力数据能判断出是否存在疲劳破坏的风险,从而协助分析车身零件疲劳开裂的原因,并结合CAE分析提出相应对策。此外,实施对策后,以相同工况再次进行应力测试,通过分析疲劳开裂对策后状态测量所得的应力数据,可快速判断其对策的有效性,从而提高对策成功率,确保新车型按时投产。

Based on the Study of Stress Test to Analyze and Verify the Cracking Problem on Vehicle Body Parts after the Durability Test

Stress test is commonly used automobile industry fatigue life analysis technique,when there is an issue that cracking happened on the spot of the body parts,put down strain gauge in the position of stress concentration,and then run the vehicle on the specific rough road to measure the data of stress,combined with the material fatigue limit and the S-N curve of this material,through the analysis of stress data to determine whether there is the risk of fatigue failure.This work can help to analyze the cause of body parts fatigue cracking,at the same time combining the CAE analysis,we can find out the corresponding countermeasures.In addition,after the implementation of the countermeasures,we can measure the stress date again,under the same working condition.By analyzing the stress data after the fatigue cracking countermeasures,the effectiveness of the countermeasures could be quickly judged,so as to improve the success rate of countermeasures and ensure that the new model was put into production on time.