Laser Powder Deposition of Tool Steels: Strategies Leading to Homogeneous Parts

Abstract:

Article Preview

The microstructure and properties of tool steel parts built by laser powder deposition (LPD) depend considerably on the build-up strategy and on the processing parameters used. This dependence can lead to inconsistent results which may limit the widespread acceptance of LPD. There is, thus, a need for efficient process optimisation tools that take into consideration the complex phase transformations that may occur during the part build-up process and their effect on final properties. A model coupling finite element heat transfer calculations with transformation kinetic theory has been developed, which allows the microstructure and property distributions in parts produced by LPD to be predicted. Application of this model to the deposition of tool steels not only explains the origin of the heterogeneous distribution of properties usually mentioned in the literature but also allows designing build-up strategies that consistently lead to homogeneous, high quality parts. Its application to the study of the influence of substrate pre-heating and idle time between the deposition of consecutive layers is illustrated in the present paper.

Info:

Periodical:

Materials Science Forum (Volumes 514-516)

Edited by:

Paula Maria Vilarinho

Pages:

739-743

DOI:

10.4028/www.scientific.net/MSF.514-516.739

Citation:

L. Costa et al., "Laser Powder Deposition of Tool Steels: Strategies Leading to Homogeneous Parts", Materials Science Forum, Vols. 514-516, pp. 739-743, 2006

Online since:

May 2006

Export:

Price:

$35.00

[1] J. Mazumder et al.: JOM Vol. 49/5 (1997), pp.55-60.

[2] M.L. Griffith et al.: Thermal behavior in the LENS process; Solid Freeform Fabrication Symposium, 1998. University of Texas at Austin.

[3] J. Mazumder, A. Schifferer and J. Choi: Mater. Res. Innov. Vol 3 (1999), pp.118-131.

[4] G. Link, PhD thesis: Layered manufacturing of laser deposited carbon steels. 1999. Stanford University.

[5] J.Y. Chen and L. Xue: Microstructural characteristics of laser-clad AISI P20 tool steel; 1st International Surface Engineering Congress and 13th IFHTSE Congress, 2002. ASM International.

[6] M.L. Griffith et al., Understanding the microstructure and properties of components fabricated by laser engineered net shaping (LENS); Solid Freeform and Additive Fabrication - Materials Research Society Symposium, 2000. Materials Research Society.

[7] L. Costa et al.: Mater. Sci. Forum Vol. 473-474 (2005), pp.315-320.

[8] R. Colaço and R. Vilar: Scripta Mater. Vol. 38/1 (1998), pp.107-113.

In order to see related information, you need to Login.