CAJ | 학술논문

开展了定向凝固镍基合金 DZ125高温循环变形特性的试验研究;试验包括纵向[001]、横向[010]和45o[011]三个晶向;温度包括室温、650℃、760℃、850℃和980℃.试验观察到材料变形的率相关、循环硬化/软化、平均应力松弛等力学现象.试验还得到了这些力学行为与温度、晶向、应变率、应变范围的关系.基于以上的材料变形特征,采用各向异性扩展的 Chaboche 统一型粘塑性本构模型对 DZ125合金的力学特性进行了本构建模研究.开发了基于遗传算法的材料参数提取和优化方法.并通过 ABAQUS 用户子程序(UMAT)结合有限元方法,进行了数值模拟验证和变形预测.
개전료정향응고얼기합금 DZ125고온순배변형특성적시험연구;시험포괄종향[001]、횡향[010]화45o[011]삼개정향;온도포괄실온、650℃、760℃、850℃화980℃.시험관찰도재료변형적솔상관、순배경화/연화、평균응력송이등역학현상.시험환득도료저사역학행위여온도、정향、응변솔、응변범위적관계.기우이상적재료변형특정,채용각향이성확전적 Chaboche 통일형점소성본구모형대 DZ125합금적역학특성진행료본구건모연구.개발료기우유전산법적재료삼수제취화우화방법.병통과 ABAQUS 용호자정서(UMAT)결합유한원방법,진행료수치모의험증화변형예측.
@@@@High-temperature cyclic deformation experiments carried out for directionally solidified Ni-base DZ125. Tests include three different directions: vertical [001], transverse [010] and experiments were done at room temperature, and the temperature of 760℃, 850℃, 980℃. The rate-dependent, cyclic hardening /softening, and cyclic relaxation of mean stress phenomena have been observed in experiment. These tests also obtained relationship between these mechanical behavior and temperature, crystal, strain rate, and strain amplitude. Based on the above deformation characteristics, the modified anisotropic Chaboche unified visco-plastic constitutive modeling is used to model the mechanical characteristics of DZ125. Genetic algorithm optimization methods are used to obtain material parameters. Numerical simulation and deformation forecast were done by coding the user’s material subroutine (UMAT) in ABAQUS platform.o[011]. The 45