螺纹短收尾表面折叠形成机理及滚压工艺参数仿真  

Simulation of the Mechanism of Folding Formation on the Surface of Short End Thread and Rolling Process Parameters

作　　者：林忠亮 张振峰 许学石 李浩楠 唐伟 白清顺[1] LIN Zhongliang;ZHANG Zhenfeng;XU Xueshi;LI Haonan;TANG Wei;BAI Qingshun(School of Mechatronics Engineering,Harbin Institute of Technology,Harbin 150001,China;Tianjin Key Laboratory of Fastening Technology,Tianjin 300300,China;Aerospace Precision Products Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]哈尔滨工业大学机电工程学院,哈尔滨150001 [2]天津市紧固连接技术企业重点实验室,天津300300 [3]航天精工股份有限公司,天津300300

出　　处：《材料导报》2024年第22期243-249,共7页Materials Reports

基　　金：天津市紧固连接技术企业重点实验室开放课题(TKLF2022-01-B-03)。

摘　　要：短收尾螺纹螺栓具有结构紧凑、质量轻、连接可靠等优点,在航空航天领域中被广泛使用。然而在螺栓加工时,收尾区域容易产生折叠缺陷,严重影响螺栓的疲劳寿命。因此需要开展螺纹短收尾表面折叠形成机理及工艺参数影响的研究。首先,建立了螺纹及其收尾滚压的有限元数值仿真模型,分析了短收尾折叠缺陷的形成过程,揭示了螺纹短收尾表面折叠的形成机理。之后,探究了收尾滚压工艺对收尾折叠量的影响,构建了滚压工艺参数-折叠量数学回归模型,并对滚压工艺参数进行了优化。研究结果表明:螺纹短收尾表面折叠主要出现在加工后期,滚丝轮收尾对螺栓螺纹收尾圆弧过渡区域产生挤压作用是造成折叠的主要原因。随着滚压加工的进行,过渡部分厚度越来越小,材料剧烈变形,会进一步导致折叠缺陷的加重。基于构建的滚压工艺参数-折叠量数学模型,分析发现进给量对折叠量的影响显著,随着其取值的增加,收尾折叠呈现先减小后增大的变化趋势。The bolts with short end thread are widely used in the aerospace industry due to their advantages of compact structure,light weight,and reliable connection.However,during the processing of bolt,the end area is prone to producing folding defect,which seriously affects the fatigue life of the bolt.Therefore,it is necessary to conduct research on the mechanism of surface folding formation and the influence of process parameters on the short end of threads.Firstly,a numerical simulation model with finite element was established on the thread and its end rolling process,and the forming process of short end folding defects was analyzed.Correspondingly,the folding formation mechanism was revealed.Afterwards,the influence of the effect of the end rolling process on the folding size was explored,and a mathematical regression model was constructed between rolling process parameter and folding size.The rolling process parameters were also optimized.The research results indicate that the surface folding of short end threads mainly occurs in the later stage of bolt processing,which is caused by the extrusion effect of the end rolling wheel on the transition area of the thread end-arc region in bolt.As the processing progresses,the thickness of the transition area becomes smaller and the material undergoes severe deformation,which can further lead to the aggravation of folding defects.Based on the mathematical model between rolling process parameter and folding size,it is indicated that the feed rate impacts most significantly the folding size.And as the folding size increases,the final folding shows a variation tendency of first decreasing and then increasing.

关 键 词：短收尾螺纹 折叠 滚压工艺 数值仿真 

分 类 号：TG131.3[一般工业技术—材料科学与工程] TG376.3[金属学及工艺—合金]