Study on Laser-TIG Dissimilar Welds of Cemented Carbide and Invar Alloys Welded with CO2 Laser

Author

Xu, P.Q. ; Yu, Z.S. ; Gong, H.Y. ; He, J.P. ; Lu, F.G. ; Cui, H.C. ; Tang, X.H.

Author_Institution

Coll. of Mater. Eng., Shanghai Univ. of Eng. Sci., Shanghai, China

fYear

2010

fDate

19-21 June 2010

Firstpage

1

Lastpage

4

Abstract

Invar alloy has lower thermal expansion and is widely used. However, its intensity is too low to meet the requirement of industry. In order to improve its high-temperature strength, WC-Co cemented carbide was welded to invar alloy using high energy Laser-TIG (Tungsten Inert Gas) hybrid welding. WC migration phenomenon was discovered in welding process and its corresponding mechanism was discussed. Microstructure at different interface was discussed and the hardness profile was measured. The results showed: (1) Butt joint of WC-Co/ invar alloy manifested well penetration without any filler materials; (2) WC migration near WC-Co/ weld interface was owed to synthesis action including stirring effects of welds, intrinsic Stress, high pressure of molten materials and ionized shielding gas, interface reaction and surface tension.

Keywords

Invar; arc welding; cermets; crystal microstructure; gas lasers; hardness; laser beam welding; surface tension; welds; Tungsten inert gas; carbon dioxide laser; cemented carbide; hardness profile; intrinsic stress; invar alloys; ionized shielding gas; laser-TIG dissimilar welds; microstructure; migration phenomenon; molten materials; stirring effects; surface tension; thermal expansion; Gas lasers; Joining materials; Microstructure; Optical materials; Optical wavelength conversion; Stress; Surface tension; Thermal expansion; Tungsten; Welding;

fLanguage

English

Publisher

ieee

Conference_Titel

Photonics and Optoelectronic (SOPO), 2010 Symposium on

Conference_Location

Chengdu

Print_ISBN

978-1-4244-4963-7

Electronic_ISBN

978-1-4244-4964-4

Type

conf

DOI

10.1109/SOPO.2010.5504311

Filename

5504311