Surface hardening of steel using a high power diode laser
Pashby, I. R., Barnes, Stuart and Bryden, B. G.. (2003) Surface hardening of steel using a high power diode laser. Journal of Materials Processing Technology, Volume 139 (Number 1-3). pp. 585-588. ISSN 0924-0136Full text not available from this repository.
Official URL: http://dx.doi.org/10.1016/S0924-0136(03)00509-0
Heat treating the surface of medium carbon steels to produce a hardened layer whilst retaining a tough core is widespread throughout general engineering and may be accomplished by using a number of different sources of energy; flame and induction heating being common. In addition, the use of high power lasers is also a well-established process. The benefits attributed to the use of lasers are that they provide localised heat input, negligible distortion, the ability to treat specific areas, access to confined areas and short cycle times. Nd:YAG and CO, systems have both been used in this application for a number of years but restrictions to the wide spread use of lasers can be related to factors such as capital cost, perceived reliability of equipment, low area coverage rates and complexity of operation. Recently, a new category of high power industrial lasers has become commercially available which have the potential to overcome some of these barriers. Based on semi-conductor technology, high power diode lasers are reliable, easy to use, compact systems capable of producing a relatively large output spot. The current work has investigated the relationships between laser power and processing speed when using a 1.2 kW diode laser to harden a plain carbon and an alloy steel. The steels, British Standard 080M40 and 817M40, have similar carbon contents (0.4%), similar Mn contents (0.8%), but in addition 817M40 contains 1.75% Ni, 0.8% Cr and 0.25% Mo. Laser powers in the range 400-1000 W were used in conjunction with surface speeds of 50-1700 mmVmin.
Microstructural examination of the treated surfaces revealed that conditions within the range examined were capable of producing structural changes and associated increases in hardness. Affected depths and maximum hardness achieved varied with power and speed, as well as with steel type. Hardened depths of greater than 0.5 mm were observed in both the plain carbon and the alloy steels. As would be expected, the maximum hardening effect was observed in the alloy steel, as was the maximum hardness.
The work has demonstrated the technical capability of diode lasers in surface hardening both plain carbon and alloy steel with practical case depths being achieved. (C) 2003 Elsevier Science B.V. All rights reserved.
|Item Type:||Journal Article|
T Technology > TS Manufactures
T Technology > TA Engineering (General). Civil engineering (General)
|Divisions:||Faculty of Science > WMG (Formerly the Warwick Manufacturing Group)|
|Journal or Publication Title:||Journal of Materials Processing Technology|
|Official Date:||20 August 2003|
|Number of Pages:||4|
|Page Range:||pp. 585-588|
|Access rights to Published version:||Restricted or Subscription Access|
|Title of Event:||9th International Manufacturing Conference|
|Location of Event:||HONG KONG, PEOPLES R CHINA|
|Date(s) of Event:||AUG 16-17, 2000|
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