振动场作用下变截面非晶零件的微近净成形机理与方法研究

Metallic glasses have a broad application prospect in micro-manufacture field, but the progress of micro forming technology of metallic glass is slow. There are some key problems urgently await to be solved, for example, it is especially important to ensure the multiaxial uniform deformation of the blank while forming complex miniature amorphous parts. But there is no effective methods to solve this problem because the high apparent viscosity due to the influent of the size effect. Therefore,based on the result of the previous studies, this project proposes a new micro net-shape forming method of complex miniature amorphous parts based on the theory of decreasing viscosity by vibration field, and carry out the research on the related technology and theories. The detailed contents are as follows: the rheological mechanism, calculation of the apparent viscosity and the characterization of the micro forming ability of metallic glasses effect by vibration field; the mechanisms of the effect of vibration parameters on the free volume and mechanical property of amorphous parts; the precision control theory of complex amorphous micro parts; A variable cross-section cup-shaped amorphous part is taken as an example, the net-shape forming theory of complex miniature amorphous parts under the effect of vibration field will created by numerical simulation and experimental study. Through the implementation of this project, the geometry size effect during the micro forming of amorphous will be overcome, this will improve the micro manufacturing level of our country and will be advantageous to expand the industrialized application scope of block metallic glasses. Therefore, this project has important theoretic value and practical significance.

非晶合金在微制造领域具有广阔的应用前景，但非晶微成形技术发展缓慢，还存在一些亟待解决的关键问题。例如，在成形复杂微型非晶零件时，保证非晶坯料的多轴均匀变形尤为关键，但由于几何尺寸效应的影响，微成形时的表观粘度高，目前还没有较好的解决办法。为此，在前期研究的基础上，本项目提出基于振动降粘的复杂微型非晶零件的微近净成形新方法，并开展相关理论和技术研究，具体内容包括：振动场作用下非晶材料的流变机理、表观粘度计算及微成形能力的表征；振动参数对非晶合金自由体积和零件性能的影响机理；复杂微型非晶零件成形精度的控制理论；以变截面杯形微型非晶零件为例，建立复杂微型非晶零件在振动场作用下的近净成形理论。本项目的实施，将通过振动降粘较好地克服非晶微成形中的几何尺寸效应问题，有利于提高我国微系统零部件的制造水平和扩大块体非晶合金的工业化应用范围。因此，本项目的实施具有重要的理论价值和实际意义。

本项目从实验和理论两个方面系统研究了振动场作用下非晶合金的微流动及摩擦行为、超塑性流变机理、复杂微型零件的成形精度控制理论等基础问题；给出了振动参数对非晶合金微成形能力的影响规律，并对振动影响非晶合金微成形能力的行为进行了评价。最后以MEMS 关键零件为应用对象，系统研究振动场作用下非晶合金的微成形工艺、微成形装置和模具结构。