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

激光成形（LF）是一种通过控制温度梯度和由扫描激光束快速吸收功率产生的热应力来实现金属板成形的过程。LF不需要硬模具，具有小批量制造和快速成型钣金部件的灵活性。LF还可以用于精细调整钣金部件，例如焊接前的装配。该项目的目标是推进LF技术的知识状态，并开发LF生产具有控制尺寸，机械性能和微观结构的钣金部件的能力，并显着提高LF工艺的精度，可扩展性和可靠性。该项目将开发LF的数值模型，通过将微观结构转变分析与热学和力学分析相结合，并结合高温和高应变率下的准确材料数据，大大提高了预测能力和准确性；并通过详细的过程中和过程后表征进行积极的实验程序来验证模型。其他热机械制造方法将能够利用本项目中开发的耦合热-机械-微观结构模型的改进理解和预测能力。该项目的成功将为制造高性能但传统上难以成型的材料开辟新的机会，从而导致创新应用，从而开辟新的设计选择。

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.