高强钢板残余应力的测量研究
时间:2021-01-06 20:09 来源:毕业论文 作者:毕业论文 点击:次
摘要:本文提出了一种残余应力测量的新方法——比容差法。首先分别从冷镦、冷轧、热轧工艺出发,通过比容差法和热膨胀实验数据进行分析,得出了不同压力加工工艺下材料内部的三维残余应力,并与传统的测量残余应力方法,即盲孔法得到的数据进行比较分析,结果表明,比容差法可用于精确且定量的测量不同压力加工方式下材料内部产生的残余应力,且较之盲孔法实验结果,有较好一致性。其次,就切割对残余应力释放的影响规律进行了讨论,得出切割对残余应力释放的影响随着薄板尺寸的增大而减小,当薄板尺寸进一步增大时,总会存在一个临界尺寸使得切割对残余应力释放的影响减小至零。最后,对热轧高强钢薄板内部残余应力不同方向上的残余应力分布规律进行了研究,结果表明,对于热轧薄钢板,在沿轧向和垂直轧向上残余应力都是由中心向边部递增,且递增的趋势变缓。 61922 毕业论文关键词:比容差法;高强钢;残余应力;盲孔法 A Study on Measurement of Residual Stress of High Strength Steel Abstract: This paper, a new method for measuring residual stress is proposed--The specific volume method.We did experiments on cold heading,cold rolling and hot rolling three kinds of different processes to analysis the data of specific volume method and thermal expansion experiment.Three dimensional residual stresses in the material under different pressure processing are obtained,and took experiment of blind hole method to contrast to the experimental data.It was showed that the specific volume method can be used for measuring the residual stress that caused by different processing pressure.Compared with the results of blind hole method,the experimental results have good consistency.Next,the influence of cutting on the residual stress release is discussed,it was showed that the effect of cutting on the release of residual stress decreases with the increase of the sheet’s size,we found that there will always be a critical dimension to reduce the impact of the residual stress release to zero when the sheet size is further increased.Finally the distribution of residual stress in hot rolled high strength steel in different directions was studied.The result showed,for hot rolled steel sheet,the residual stress is increased by the center to the edge, and the increasing trend is slow along the rolling direction and the vertical rolling direction. Keywords:Specific volume;high strength steel;residual stress;blind hole method 1 绪论 1 1.1 高强钢简介 1 1.1.1 高强钢种类 1 1.1.2 新种类高强钢 2 1.2 残余应力 2 1.2.1 残余应力的产生 2 1.2.2 残余应力的危害 2 1.2.3 影响表面残余应力的主要因素 3 1.3 残余应力测量方法 3 1.3.1 盲孔法 4 1.3.2 切条法 4 1.3.3 磁测法 5 1.3.4 X射线衍射法 5 1.3.5 超声波法 6 1.3.6 中子衍射法 6 1.4 现有残余应力测量方法分析 6 1.5 比容差法测量残余应力 7 1.6 研究的意义与内容 7 1.6.1 研究的意义和目的 (责任编辑:qin) |