Investigation of an active stressing technique for delaying fracture during laser cutting of alumina

Research output: Contribution to conferencePaper

7 Citations (Scopus)

Abstract

During a variety of high-speed laser cutting operations, full work-piece support is not always practical or possible. As a result, costly premature fractures and associated damage such as chips, burrs, and cracks (ranging from the micro- all the way to the macro-scale) can result. In most instances, the resulting stresses are primarily mechanical in nature and arise from the bending and/or twisting moments from the still attached scrap. Even if the scrap weight remains relatively constant (as is usually the case), mixed-mode fracture is all but inevitable since the remaining (supporting) section is continuously diminishing as the cut progresses. Given the predominantly mechanical, and therefore predictable nature of the resulting stresses, it is conceivable that intentionally induced compressive stresses due to an off-focus laser might be used to control (or at least, delay) such fractures. In this paper, the possibility of using a tailored laser-heating scenario ahead of a progressing cut to "actively" induce compressive thermal-stresses to control fracture, during cutting of cantilevered plate, was investigated. A numerical simulation of this active stressing approach was achieved by using a customized finite-element formulation that was previously employed to model dual-beam laser machining. During the complex 3-D simulations, probabilistic fracture mechanics was used to quantify the influence of the induced compressive stresses on the time and nature of the fracture. The effect of important parameters such as laser beam diameter, incident power density, positioning of the laser with respect to cut, as well as timing were then studied with respect to the goal of reducing and/or delaying the likelihood of fracture.

Original languageEnglish (US)
Pages173-179
Number of pages7
DOIs
StatePublished - Dec 1 2004
Event2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004 - Anaheim, CA, United States
Duration: Nov 13 2004Nov 19 2004

Other

Other2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004
CountryUnited States
CityAnaheim, CA
Period11/13/0411/19/04

Fingerprint

Alumina
Lasers
Compressive stress
Laser beam machining
Laser heating
Fracture mechanics
Thermal stress
Laser beams
Macros
Cracks
Computer simulation

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Akarapu, R., & Segall, A. E. (2004). Investigation of an active stressing technique for delaying fracture during laser cutting of alumina. 173-179. Paper presented at 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States. https://doi.org/10.1115/IMECE2004-61243
Akarapu, R. ; Segall, Albert Eliot. / Investigation of an active stressing technique for delaying fracture during laser cutting of alumina. Paper presented at 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States.7 p.
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Akarapu, R & Segall, AE 2004, 'Investigation of an active stressing technique for delaying fracture during laser cutting of alumina', Paper presented at 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States, 11/13/04 - 11/19/04 pp. 173-179. https://doi.org/10.1115/IMECE2004-61243

Investigation of an active stressing technique for delaying fracture during laser cutting of alumina. / Akarapu, R.; Segall, Albert Eliot.

2004. 173-179 Paper presented at 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States.

Research output: Contribution to conferencePaper

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Akarapu R, Segall AE. Investigation of an active stressing technique for delaying fracture during laser cutting of alumina. 2004. Paper presented at 2004 ASME International Mechanical Engineering Congress and Exposition, IMECE 2004, Anaheim, CA, United States. https://doi.org/10.1115/IMECE2004-61243