P. R. Ding
,
D. Y. Ju
,
T. Lnouc and E. de Vries( 1) MSC Japan Ltd.
,
Osaka
,
Japan 2) Saitama Institute of Technology
,
Saitama
,
Japan 3) Kyoto Universily
,
Kyoto
,
Japan 4) MacNeal - Schwendler (E. D. C. ) B. V.
,
Gouda
,
The Netherlands)
金属学报(英文版)
A method to simulate processes of forging and subsequent heat treatment of an axial symmetric rod is formulated in eulerian description and the feasibility is investigated. This method uses finite volume mushes for troching material deformation and an automatically refined facet surface to accurately trace the free surface of the deforming material.In the method,the deforming work piece flows through fixed finite volume meshes using eulerian formulation to describe the conservation laws,Fixed finite volume meshing is particularly suitable for large three-dimensional deformation such as forging because remeshing techniques are not required, which are commonly considered to be the main bottelencek in the ssimulations of large defromation by using the finite element method,By means of this finite volume method, an approach has been developed in the framework of "metallo-thermo-mechanics" to simulate metallic structure, temperature and stress/strain coupled in the heat treatment process.In a first step of simulation, the heat treatment solver is limited in small deformation hypothesis,and un- coupled with forging. The material is considered as elastic-plastic and takes into account of strain, strain rate and temperature effects on the yield stress.Heat generation due to deformation,heat con- duction and thermal stress are considered.Temperature - dependent phase transformation,stress-in- duced phase transformation,latent heat,transformation stress and strain are included.These ap- proaches are implemented into the commerical commercial computer program MSC/SuperForge and a verification example with experimental date is given as comparison.
关键词:
finite volume method
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null
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null
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null
,
null
张亚军
,
龚志江
,
汪凯
,
邵杰
,
朱军
材料开发与应用
本文通过对锻造、轧制及热处理工艺的研究,测试了材料的力学性能、晶粒度及金相组织,确定最佳工艺为轴向镦粗径向拔长+三向循环镦粗拔长的锻造工艺,换向轧制的开坯轧制工艺,950℃× 90 min的热处理工艺,该工艺制备的材料符合性能要求.
关键词:
细晶
,
深冲钽带
,
锻造
,
换向轧制
,
热处理
刘静
,
王平
稀有金属材料与工程
采用DEFORM-3D软件模拟研究了模具温度、压下速度等因素对半固态6061铝合金触变模锻过程.结果表明:6061合金在650℃料温,400℃模温,50 mm/s压下速度时半固态金属模锻成形过程较为理想;半固态模锻件经T5处理后,硬度(HV)可达到2166MPa,高于常规低压铸件170.5％,模拟结果与实际符合很好.
关键词:
半固态
,
模锻
,
DEFORM-3D
,
模拟
,
硬度
李凯
,
杨平
,
沙爱学
,
颜孟奇
金属学报
doi:10.3724/SP.J.1037.2014.00003
针对α/β型TC18钛合金大型锻棒中心与边部的性能差异,利用EBSD技术研究了β相的组织差异、织构差异及形变程度差异,并考察了β相的这些差异对遵循Burgers关系的αp相取向及球化速率的影响.结果表明,锻态TC18钛合金中的β相处于不同程度的形变状态,随位置不同而具有不同的织构,中心位置β相具有再结晶织构<100>的特点,并且存在显著的晶粒尺寸不均匀性,这些因素对中心与边部的性能差异有主要贡献.αp相的球化过程主要在β相晶内亚晶界上完成,前期随形貌由片状向方块状的变化,取向关系变化很小;后期向球形过渡时,取向关系偏差较大.β相晶粒内的取向差是衡量加工硬化对强度贡献的有效参数,而α/β两相的取向关系与理想Burgers关系的偏差是揭示球化速度和形变β相晶粒回复程度的有效参数.
关键词:
钛合金
,
锻造
,
织构
,
相变
