摘要
目的揭示钛合金孔型轧制的力学性能规律和微观组织演化机制。方法利用有限元软件Abaqus对Ti6554钛合金棒料进行多道次孔型轧制模拟。研究不同轧制温度(500、600、700℃)对驱动辊轧制力、等效塑性应变和温度分布的影响规律,并比较不同轧制温度下棒料轧制后的微观组织和力学性能。结果与初始棒料相比,轧制后棒料的微观组织更加均匀,晶粒得到了显著细化。随着轧制温度的升高,棒料内部的位错密度显著降低,棒料的室温抗拉强度从1186.3 MPa降低至984.4 MPa,屈服强度由1165.2 MPa降低到953.8 MPa;然而,断后伸长率从13.1%增长到27.8%,冲击韧性从10.8 J/cm2增长到29.7 J/cm^(2)。结论通过有限元模拟和实际实验相结合的方法,从驱动辊轧制力、棒料的温度和截面尺寸方面验证了有限元模拟的准确性和可靠性。在600℃轧制时,棒料内部各区域的等效塑性应变分布更加均匀,晶粒尺寸及组织的均匀性得到显著改善。棒料的拉伸断口有着多而深的等轴韧窝,呈现出韧性断裂特征;而在500℃轧制时,断口处韧窝的数量较少,并且存在微小的解理平面,表现出准解理断裂特征。
The work aims to reveal the mechanical property law and microstructure evolution mechanism of the titanium al-loy during hole rolling.The multi-pass groove rolling simulation of Ti6554 titanium alloy bar was conducted by the finite ele-ment software Abaqus.The effect laws of different rolling temperatures(500,600,700℃)on the rolling force of the driving roller,equivalent plastic strain and temperature distribution were investigated,and the microstructure and mechanical properties of the rolled bars under different rolling temperatures were compared.After rolling,the microstructure of the bar was more uni-form,and the grain was more refined.As the rolling temperature increased,the dislocation density inside the bar material de-creased significantly,the room temperature tensile strength decreased from 1186.3 MPa to 984.4 MPa,and the yield strength decreased from 1165.2 MPa to 953.8 MPa.However,the elongation increased from 13.1%to 27.8%,and the impact toughness increased from 10.8 J/cm^(2) to 29.7 J/cm^(2).Through the method of combining finite element simulation and field experiment,the exactitude and dependability of the finite element simulation are verified from the rolling force of the driving roller and the temperature and cross-section size of the bar.Under 600℃rolling,the distribution of equivalent plastic strain within the bar material is more uniform,and the grain size and microstructural uniformity are significantly improved.The tensile fracture of the bar exhibits numerous and deep equiaxed dimples,indicating a ductile fracture characteristic.In contrast,under 500℃ roll-ing,the number of dimples at the fracture surface is reduced,and small cleavage planes are present,reflecting a quasi-cleavage fracture characteristic.
作者
孟亚飞
王庆敏
武川
徐广胜
王孟超
姚磊
MENG Yafei;WANG Qingmin;WU Chuan;XU Guangsheng;WANG Mengchao;YAO Lei(National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die&Mould,Tianjin University of Technology and Education,Tianjin 300222,China;Shougang Jingtang United Iron&Steel Co.,Ltd.,Hebei Tangshan 063200,China;School of Material Engineering,Shaanxi Polytechnic Institute,Shaanxi Xianyang 712099,China)
出处
《精密成形工程》
北大核心
2025年第8期12-24,共13页
Journal of Netshape Forming Engineering
基金
国家自然科学基金(52075386,52475394)
天津市自然科学基金多投入重点项目(22JCZDJC00650)。
关键词
孔型轧制
有限元模拟
等效塑性应变
微观组织
力学性能
hole rolling
finite element simulation
equivalent plastic strain
microstructure
mechanical properties
