空心叶片激光直接制造中超细柱状晶与结构特征的相互作用机制

项目名称： 空心叶片激光直接制造中超细柱状晶与结构特征的相互作用机制

项目编号： No.51275392

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 机械、仪表工业

项目作者： 张安峰

作者单位： 西安交通大学

项目金额： 80万元

中文摘要： 具有复杂冷却流道的先进空心叶片，结构越来越复杂，壁厚越来越薄，给叶片制造带来了巨大的挑战。用激光直接成形（LDF）空心叶片是一种很有发展潜力的先进成形技术。但LDF超细柱状晶定向生长与空心叶片结构特征会相互作用，在搭接处和上下层之间沿基材定向生长方向柱状晶会转变为非柱状晶，从而严重影响超细柱状晶空心叶片的力学性能。采用数值模拟和定向凝固原理相结合的方法，研究空心叶片结构特征与超细柱状晶定向生长的相互作用规律，探讨LDF空心叶片柱状晶在搭接处和上下层之间非柱状晶的形成条件。阐明空心叶片结构特征与柱状晶定向生长的相互作用机制，并揭示LDF空心叶片柱状晶在搭接处和上下层之间非柱状晶的形成机理，为LDF健全的超细柱状晶复杂空心叶片奠定基础。研究成果即可为燃气轮机和航空发动机提供一种制造超细柱状晶空心叶片的新思路，又可用于现役定向凝固叶片的修复，满足国家重大装备制造和国防工业对空心叶片制造的急需。

中文关键词： 激光直接成形；结构特征；定向生长；空心叶片；柱状晶

英文摘要： Advanced hollow blades with complex cooling channel, thinner wall-thickness and more structural characteristics has brought great challenges to blades manufacturing technology. Laser Direct Forming (LDF) is an advanced forming technology with great potential to fabricate hollow blades. However, the structural characteristics of hollow blades will affect the growth of superfine columnar crystal in LDF, so the columnar crystal at the overlapping area of different layers and different tracks may transformed into non-columnar crystal and this transformation will affect the mechanical properties of hollow blades seriously. The study focuses on the interaction mechanism between structural characteristics of hollow blades and the growth of superfine columnar crystal using numerical simulation and solidification principle, and the formation conditions of non-columnar crystal at the overlapping area of different layers and different tracks are investigated in detail. It proposes to illustrate the interaction mechanism between structural characteristics of hollow blades and the growth of superfine columnar crystal and also want to clarify the formation mechanism of non-columnar crystal at the overlapping area of different layers and different tracks. This investigation will lay a foundation for the hollow lades forming wi

英文关键词： laser direct forming；complex structure；orientation growth；hollow blades；columnar crystal