US Army ARDEC Joint Fuze Technology Program (JFTP) Task 2 Report: Quasi-Static Tensile Tests of Microfabricated Electrodeposited (LIGA) Ni Alloys

Published: May 31, 2018

Author(s)

Li-Anne Liew, David T. Read, Ryan M. White, Nicholas Barbosa

Abstract

The LIGA process (Lithographie, Galvanoformung, Abformung, or lithography, electrodeposition, shaping) offers the possibility of mass producing strong mesoscale (order of a few mm or less) metal components of nearly any planar shape. Multilayer deposition has been developed to create three-dimensional shapes. The overall objective of this multi-year project is to enable the use of the Johnson-Cook flow and fracture models for evaluation of structural elements made from two LIGA alloys of interest, by providing the material property data at the microscale needed to carry out structural analyses utilizing these models. This report documents the first milestone in the project, which is the measurement of the room-temperature tensile properties of two LIGA alloys of one commercial vendor’s proprietary materials – one optimized for strength and the other for ductility, with nominal thicknesses 190 µm and 170 µm respectively – at strain rates 0.001/s and 1/s, utilizing four specimen geometries with gauge widths ranging from 75 µm to 700 µm. Test methods adapted to the scale of these materials were applied. Results, measurement uncertainties, and statistical variations for the ultimate tensile strength and apparent Young’s modulus are quantified for all combinations of these material/geometry/rate variations. In addition, preliminary studies were conducted into the effects of low-temperature annealing on the materials’ strength, and use of electron back scatter diffraction to observe the microstructure.
Citation: NIST Interagency/Internal Report (NISTIR) - 8182
Report Number:
8182
Pub Type: NIST Pubs

Keywords

LIGA, mechanical properties, microtensile, nickel, quasi-static, strain rate, tensile
Created May 31, 2018, Updated November 10, 2018