摘要
目的研究钛合金超声滚压加工中的不同工艺参数对表层特性指标的影响,得到最佳工件表面质量的加工参数。方法运用超声滚压加工技术,采用一维超声振动滚压装置和CA6140B/A型号的车床对钛合金TC4进行试验,并结合赫兹接触理论建立滚压力与残余应力的理论模型。采用ABAQUS仿真分析滚压力对残余应力的影响。结果对比分析发现,仿真结果的变化趋势和试验结果相同,即在其他加工参数不变的条件下,表面残余应力随着滚压力的增加,呈现先增大后减小的趋势,在静压力600 N时的残余应力值最大。通过超景深和粗糙度仪测得,超声滚压力600 N时,表面粗糙度达到最小,在500~800 N时能获得较好的表明质量,超过800 N后会对表面产生损伤,出现裂纹。由显微硬度仪测得,表面硬度和硬化程度则随着滚压力的增加而不断升高,说明表面硬度越大时,表面粗糙度并不是越小。通过金相组织图和XRD物相分析发现,随着滚压力的增大,塑性变形程度增加,β-Ti衍射峰越来越弱,晶粒细化程度越来越明显。结论超声滚压力工艺参数在一定范围内会产生良好的加工效果。该研究为超声滚压钛合金材料奠定了理论基础。
The work aims to study the effects of different process parameters on the surface properties of titanium alloy in the ultrasonic burnishing process,to obtain the processing parameters of the best workpiece surface quality.By the ultrasonic processing technology,Titanium alloy TC4 was tested with one-dimensional ultrasonic vibration burnishing device and CA6140B/A lathe and the theoretical model of ultrasonic burnishing pressure and residual stress was established on the basis of the Hertz theory.Then,the effect of different ultrasonic burnishing pressure on residual stress was simulated by the ABAQUS software.Through comparative analysis,the variation trend of the simulation results was the same as the experiment results.When other processing parameters were constant,the surface residual stress first increased and then decreased with the increase of the burnishing pressure,and the residual stress was the largest at 600 N burnishing pressure.The surface roughness measured by super depth of field and roughness meter reached a minimum when the burnishing pressure was 600 N,and the quality could be better when the burnishing pressure was 500~800 N,and surface damage and cracks occurred when the burnishing pressure was over 800 N.The surface hardness and the degree of hardening measured by the microhardness tester increased with the increment of the burnishing pressure,indicating that the surface hardness was not smaller when the surface hardness was larger.Through the analysis on metallographic structure and XRD phase,the degree of plastic deformation increased with the increment of burnishing pressure,and the weaker theβ-Ti diffraction peak was,the more refined the grain refinement was.The ultrasonic burnishing pressure parameters can produce good processing effect in a certain range,which provides theoretical basis for ultrasonic burnishing of titanium alloy materials.
作者
李凤琴
赵波
LI Feng-qin;ZHAO Bo(School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454003,China;School of Safety Engineering,Henan University of Engineering,Zhengzhou 451191,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2019年第10期34-40,共7页
Surface Technology
基金
国家自然科学基金(51475148,U1604255)~~
关键词
钛合金
超声滚压
表层特性
残余应力
有限元仿真
塑性变形
titanium alloy
ultrasonic rolling
surface properties
residual stress
finite element simulation
plastic deformation
