Investigation on surface roughness,residual stress and fatigue property of milling in-situ TiB_2/7050Al metal matrix composites  

作　　者：Yifeng XIONG Wenhu WANG Yaoyao SHI Ruisong JIANG Chenwei SHAN Xiaofen LIU Kunyang LIN 

机构地区：[1]Key Laboratory of High Performance Manufacturing for Aero Engine,Ministry of Industry and Information Technology,School of Mechanical Engineering,Northwestern Polytechnical University,Xi'an 710072,China [2]Engineering Research Center of Advanced Manufacturing Technology for Aero Engine,Ministry of Education,School of Mechanical Engineering,Northwestern Polytechnical University,Xi'an 710072,China [3]School of Aeronautics and Astronautics,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Journal of Aeronautics》2021年第4期451-464,共14页中国航空学报（英文版）

基　　金：National Natural Science Foundation of China(No.51775443);National Science and Technology Major Project of China(No.2017-VII-00150111)。

摘　　要：For higher efficiency and precision manufacturing,more and more attentions are focused on the surface roughness and residual stress of machined parts to obtain a good fatigue life.At present,the in-situ TiB_2/7050 Al metal matrix composites are widely researched due to its attractive properties such as low density,good wear resistance and improved strength.It is of great significance to investigate the machined surface roughness,residual stress and fatigue life for higher efficiency and precision manufacturing of this new kind material.In this study,the surface roughness including two-dimensional and three-dimensional roughness,residual stress and fatigue life of milling in-situ TiB_2/7050 Al metal matrix composites were analyzed.It was found from comparative investigation that the three-dimensional surface roughness would be more appropriate to represent the machined surface profile of milling particle reinforced metal matrix composites.The cutting temperature played a great role on the residual stress.However,the effect of increasing cutting force could slow down the transformation from compressive stress to tensile stress under 270°C.An exponential relationship between three-dimensional roughness and fatigue life was established and the main fracture mechanism was brittle fracture with observation of obvious shellfish veins,river pattern veins and wave shaped veins in fracture surface.

关 键 词：Fatigue life Metal matrix composite Residual stress Three-dimensional surface roughness TiB_2 particle Two-dimensional surface roughness 

分 类 号：V261.23[航空宇航科学与技术—航空宇航制造工程]