Laser forming near shapes in titanium

Laser forming of steel is a hot forming process with high heating and cooling rate, during which strain hardening, dynamic recrystallization, and phase transformation take place. Numerical models considering strain rate and temperature effects only usually give unsatisfactory results when applied to multiscan laser forming operations. This is mainly due to the inadequate constitutive models employed to describe the hot flow behavior. In this work, this limitation is overcome by considering the effects of microstructure change on the flow stress in laser forming processes of low carbon steel. The incorporation of such flow stress models with thermal mechanical FEM simulation increases numerical model accuracy in predicting geometry change and mechanical properties.

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Affected Characteristics Analysis of the Pulsed Laser Forming of Metal Sheet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.375-376.333 ◽

2008 ◽

Vol 375-376 ◽

pp. 333-337

Author(s):

Li Jun Yang ◽

Yang Wang

Keyword(s):

Laser Beam ◽

Pulsed Laser ◽

Metal Sheet ◽

Grain Structure ◽

Experimental Result ◽

Laser Forming ◽

Forming Process ◽

Grain Orientations ◽

Characteristics Analysis ◽

Relationship Of

Laser forming of metal sheet is a forming technology of sheet without a die that the sheet is deformed by internal thermal stress induced by partially irradiation of a laser beam. In this paper, the bending behavior of common stainless steel 1Cr18Ni9 sheet is studied after being irradiated by straight line with a Nd:YAG pulsed laser beam. The aim of the investigation is to find out the relationship of the physical behaviors of heat affected zone (HAZ) with the pulse parameters of the laser. Through the analysis of the fundamental theory of pulsed laser affected, this paper shows the affected characteristics of metal sheet with pulsed laser forming. The results show that the microstructure of HAZ of pulsed laser scanned is layered, and the micro-hardness is improved than that in matrix. The microstructures show that the deformed grain structure is inhomogeneous, that caused the grain sizes and grain orientations in HAZ to become different. By qualitative analysis of experimental result, the conclusion obtained may provide basis for theoretical investigation and possible industrial application of laser forming process in the future.

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Reverse Analysis of Scan Strategies for Controlled 3D Laser Forming of Sheet Metal

Procedia Engineering ◽

10.1016/j.proeng.2017.04.054 ◽

2017 ◽

Vol 183 ◽

pp. 369-374 ◽

Cited By ~ 8

Author(s):

H. Gao ◽

G. Sheikholeslami ◽

G. Dearden ◽

S.P. Edwardson

Keyword(s):

Sheet Metal ◽

Laser Forming ◽

Reverse Analysis

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Laser Forming for Flexible Fabrication

Journal of Ship Production ◽

10.5957/jsp.2000.16.2.97 ◽

2000 ◽

Vol 16 (02) ◽

pp. 97-109

Author(s):

Koichi Masubuchi ◽

Jerry E. Jones

Keyword(s):

Three Dimensional ◽

Low Carbon Steel ◽

High Strength Steels ◽

Cost Benefit ◽

Network Models ◽

High Strength ◽

Laser Forming ◽

Low Carbon ◽

Flat Plates ◽

Neural Network Models

A 36-month program supported by the Defense Advanced Research Projects Agency (DARPA) was conducted to demonstrate the feasibility to predictably laser form a variety of ferrous and non-ferrous metals of different thickness. Laser forming provides a method of producing complex shapes in sheet, plate, and tubing without the use of tooling, molds, or dies. By heating a localized area with a laser beam, it is possible to create stress states that result in predictable deformation. This research program has developed, refined and demonstrated constitutive and empirical, and neural network models to predict deformation as a function of critical parametric variables and established an understanding of the effect of laser forming on some metallurgical properties of materials. The program was organized into two, time-phased tasks. The first task involved forming flat plates to one-dimensional (I -D) shapes, such as, hinge bends in various materials including low-carbon steel, high-strength steels, nickel-based super alloys, and aluminum alloys. The second task expanded the work conducted in the first task to investigate three-dimensional (3-D) configurations. The models were updated, 3-D specimens fabricated and evaluated, and cost benefit analyses were performed.

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