高强韧稀土镁合金筋板类构件等温精锻工艺  

Isothermal Precision Forging Process of Mg-RE Alloy Component With High-Rib and Thin-Web

作　　者：韩修柱[1,2] 单德彬[1] 徐文臣[1] 杜志慧[2] 张绪虎[2] 

机构地区：[1]哈尔滨工业大学材料学院,哈尔滨150001 [2]航天材料及工艺研究所,北京100076

出　　处：《宇航材料工艺》2013年第3期60-65,87,共7页Aerospace Materials & Technology

摘　　要：主要研究高强韧稀土镁合金筋板类构件等温精锻工艺及随后的锻件微观组织与性能的控制。通过Deform软件对典型筋板类构件的等温精锻工艺进行模拟研究,通过分析等温精锻工艺过程中金属材料的流动趋势及可能出现的问题,提出相应的解决方案,在随后的实验过程中,成功成形出具有高筋薄腹板的典型筋板类锻件。研究结果表明:筋板类构件等温精锻过程中在两个侧筋相交的位置充填最为困难,利用有限元方法对坯料尺寸进行优化设计,有效地改善了金属在复杂模具型腔内的充填能力,并降低了等温成形载荷,成形出表面质量良好的稀土镁合金精锻件。通过200℃时效63 h后,高强韧稀土镁合金筋板类构件的强度达到峰值,其峰值抗拉、屈服强度和延伸率分别为371、243 MPa和4.07%。β'相和长周期相在基体上的弥散分布是锻件获得较高强度的主要原因。锻件断口在未时效处理状态下主要为韧性断裂,而随着时效过程的进行,断裂方式逐渐转变为准解理断裂。The isothermal precision forging process and microstructure evolution of Mg-RE component with high- rib and thin-web are studied in the article. The deform software was used to simulate the isothermal precision forging process and some problems arises during the forging process were proposed. Some methods are also proposed according to the results of simulation and the forgings with high-rib and thin-web were formed successfully. The results show that the intersected lateral ribs are difficult to fill during isothermal precision forging process. The dimension of billet is optimized according to the simulation analysis by deform software, which reduces the load of forging process and the Mg -RE component with high quality is formed successfully in the combined female dies. The optimal ageing parameter, 200~C ,63 h, is obtained,corresponding to peak ultimate tensile strength,tensile yield strength and elongation of the Mg-RE component of 371 MPa,243 MPa and 4.07% ,respectively. The strengthening β＇ phase and long period stac- king ordered phase mainly contribute to the high strength of the component. The fracture modes are changed during forging process and ageing process, i.e. ductile fracture in the forged component and cleavage fracture in the aged component.

关 键 词：筋板类构件 稀土镁合金 等温精锻工艺 时效工艺 

分 类 号：TG146.22[一般工业技术—材料科学与工程]