Diode laser beam absorption in laser transformation hardening of low alloy steel

H. Pantsar, Veli Kujanpää

Research output: Contribution to journalArticleScientificpeer-review

41 Citations (Scopus)

Abstract

Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.
Original languageEnglish
Pages (from-to)147 - 153
Number of pages7
JournalJournal of Laser Applications
Volume16
Issue number3
DOIs
Publication statusPublished - 2004
MoE publication typeA1 Journal article-refereed

Fingerprint

high strength steels
High strength steel
hardening
Laser beams
Hardening
Semiconductor lasers
diodes
laser beams
Lasers
absorptivity
lasers
surface temperature
material absorption
pyrometers
Pyrometers
melting points
calorimeters
Graphite
Aluminum Oxide
Steel

Cite this

Pantsar, H. ; Kujanpää, Veli. / Diode laser beam absorption in laser transformation hardening of low alloy steel. In: Journal of Laser Applications. 2004 ; Vol. 16, No. 3. pp. 147 - 153.
@article{045218f9d7bf4766941d86b36272f0b1,
title = "Diode laser beam absorption in laser transformation hardening of low alloy steel",
abstract = "Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46{\%} to 72{\%} depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66{\%} to 81{\%}. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85{\%} were measured.",
author = "H. Pantsar and Veli Kujanp{\"a}{\"a}",
year = "2004",
doi = "10.2351/1.1710879",
language = "English",
volume = "16",
pages = "147 -- 153",
journal = "Journal of Laser Applications",
issn = "1042-346X",
number = "3",

}

Diode laser beam absorption in laser transformation hardening of low alloy steel. / Pantsar, H.; Kujanpää, Veli.

In: Journal of Laser Applications, Vol. 16, No. 3, 2004, p. 147 - 153.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Diode laser beam absorption in laser transformation hardening of low alloy steel

AU - Pantsar, H.

AU - Kujanpää, Veli

PY - 2004

Y1 - 2004

N2 - Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.

AB - Defining and controlling the absorption of the laser beam is important since all of the heating energy is brought to the material through absorption. Even small variations in the absorption change the laser power needed by hundreds of W. In this study the absorption of a diode laser beam to low alloy steel has been measured by a liquid calorimeter and the surface temperature has been measured with a dual wavelength pyrometer. The varied processing parameters were the power intensity of the beam, the interaction time, and the angle between the surface and the optical axis of the laser beam. Surface temperatures during hardening varied from the Ac1 temperature to the melting point. Tests were done with a 3 kW diode laser with a 12×5 mm hardening optic. The absorptivity of a machined clean steel surface ranged from 46% to 72% depending on the processing parameters. Aluminum oxide blasting of the surface increased the relative amount of energy absorbed to the work piece. The coupling rates for blasted surfaces varied from 66% to 81%. Best absorptivity was achieved by applying graphite coating on the surface. Absorptivity values in excess of 85% were measured.

U2 - 10.2351/1.1710879

DO - 10.2351/1.1710879

M3 - Article

VL - 16

SP - 147

EP - 153

JO - Journal of Laser Applications

JF - Journal of Laser Applications

SN - 1042-346X

IS - 3

ER -