Tensile, creep and fatigue properties of LIGA nickel structures

Author

Cho, H.S. ; Hemker, K.J. ; Lian, K. ; Goettert, J.

Author_Institution

Dept. of Mech. Eng., Johns Hopkins Univ., Baltimore, MD, USA

fYear

2002

fDate

24-24 Jan. 2002

Firstpage

439

Lastpage

442

Abstract

Elevated temperature tensile, creep and high cycle fatigue properties of electro-deposited LIGA Ni structures have been measured and are being used to predict the reliability of LIGA based MEMS structures. Microsamples with dimensions of 100´s of microns have been LIGA fabricated and characterized in terms of their elevated temperature tensile and creep strength and their high-cycle fatigue performance. The strength of these LIGA Ni structures was found to decrease dramatically at temperatures above 200/spl deg/C. At stresses significantly below the yield strength, substantial creep deformation was also observed at moderately elevated temperatures. The fatigue life of the LIGA Ni microsamples increased with decreasing stress amplitude in a manner comparable to what has been reported for wrought Ni. An apparent fatigue limit was observed for the LIGA Ni microsamples, but the importance of component geometry on the fatigue life was also highlighted.

Keywords

LIGA; creep; electrodeposits; fatigue; high-temperature effects; nickel; tensile strength; yield strength; 200 C; MEMS structure; Ni; creep deformation; electrodeposited LIGA Ni structure; elevated temperature; fatigue life; reliability; tensile strength; yield strength; Creep; Fatigue; Mechanical factors; Micromechanical devices; Microstructure; Nickel; Temperature; Tensile strain; Tensile stress; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems, 2002. The Fifteenth IEEE International Conference on

Conference_Location

Las Vegas, NV, USA

ISSN

1084-6999

Print_ISBN

0-7803-7185-2

Type

conf

DOI

10.1109/MEMSYS.2002.984297

Filename

984297