Title :
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
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;
Conference_Titel :
Micro Electro Mechanical Systems, 2002. The Fifteenth IEEE International Conference on
Conference_Location :
Las Vegas, NV, USA
Print_ISBN :
0-7803-7185-2
DOI :
10.1109/MEMSYS.2002.984297
