Laser Forming of Sheet Metal with Controlled Dimension, Mechanical Properties, and Microstructure

激光成形是一种通过控制扫描激光能量的快速吸收而产生的温度梯度和热应力来实现金属板料成形的过程。LF不需要硬工具，并且具有小批量制造和快速成形板材零件的灵活性。LF还可以用于微调金属板零件，例如，焊接前的装配。该项目的目标是提高LF技术的知识水平，发展LF生产尺寸、机械性能和组织可控的板材零件的能力，并显著提高LF工艺的精确度、可扩展性和可靠性。该项目将通过将微观结构转变分析与热分析和力学分析相结合，并结合高温和高应变率下的准确材料数据，开发一个预测能力和精度大大提高的LF数值模型；并通过详细的过程中和后处理表征，实施积极的实验计划，以进行模型验证。其他热-机械制造方法将能够利用本项目将开发的热-机械-微结构耦合模型的改进的理解和预测能力。该项目的成功将为制造高性能但传统上难以成形的材料开辟新的机会，导致创新应用，从而打开新的设计选择。

Laser forming (LF) is a process in which sheet metal forming is achieved through controlled temperature gradients and thermal stresses produced by the rapid absorption of power from a scanning laser beam. LF requires no hard tooling and has the flexibility for low-volume fabrication and rapid prototyping of sheet metal components. LF can also be used to fine adjust sheet metal parts for, say, pre-welding fit-up. The goal of this project is to advance the state of knowledge in LF technology, and to develop capabilities for LF to produce sheet metal components with controlled dimension, mechanical properties, and microstructures, and to markedly improve accuracy, scalability and reliability of the LF process. The project will develop a numerical model for LF having much improved prediction capabilities and accuracy by coupling microstructural transformations analysis with thermal and mechanical analysis and by incorporating accurate material data at high temperatures and high strain rates; and carry out an aggressive experimental program for model validation through detailed in-process and post-process characterizations. Other thermal-mechanical manufacturing methods will be able to leverage upon the improved understanding and prediction capabilities of the coupled thermal-mechanical- microstructural model to be developed in this project.The success of the project will open-up new opportunities for manufacturing of high-performance but conventionally hard-to-form materials, leading to innovative applications, thus opening new design options.