Micro-Compression Characterization and Thermal Stability of Electrolessly Plated Nickel Phosphorus Alloy

Abstract

The micro-compression characteristic of an electrolessly plated Ni-P alloy was evaluated in this study. Specimens used in the micro-compression test were micro-pillars having a square cross-section fabricated by focused ion beam system. One side of the square cross-section was varied from 5 to 20 μm and the aspect ratio of the micro-pillars was kept at 2:1 to evaluate the sample size effect on the mechanical property. The as-plated Ni-P alloy was amorphous. The sample size effect commonly observed in mechanical properties of metallic micro-specimens was not obvious for micro-pillars fabricated from the as-plated Ni-P alloy, and all of the micro-pillars showed shear band deformation with the 0.2% yield strength at roughly 2.2 GPa. Heat treatment was conducted to study the influence on the sample size effect. After heat treatment at 300 °C for 2 h, an increase in the strength was observed in micro-pillars with all sizes. In addition, for the heat-treated specimens, the fracture strength increased from 3.1 to 4.7 GPa when cross-section of the micro-pillar decreased from 20 × 20 to 10 × 10 μm2, which revealed the sample size effect.

Electrodeposition of Ni–B Alloy Film: Effect of Current Density and Heat Treatment on Micro-Mechanical Property

“…In order to evaluate the mechanical property for the design of microcomponents, mechanical test using specimens having the size on the micro-scale are developed. [25][26][27][28] Micro-mechanical properties of Ni-P alloy films by micro-compression test are reported in a previous study, 29 an increase in the strength is observed after a 300 °C heat treatment.…”

“…The micro-compression test was conducted using a test machine specially designed for micro-sized specimens. [27][28][29] The test machine system was equipped with a flattopped indenter having a diameter of 50 μm on the tip surface. The displacement rate was kept at a constant speed of 0.1 μm s −1 in all micro-compression tests.…”

Electrodeposition and Micro-Mechanical Property Characterization of Nickel–Cobalt Alloys toward Design of MEMS Components

“…For precise evaluation of the mechanical properties on the micro-scale toward microcomponents in miniaturized electronic devices, micro-compression [1,2,[21][22][23], microtensile [24], and micro-bending [25][26][27] tests have been developed. The micro-mechanical properties of micro-grained nickel [1], nano-grained nickel [2,24,27], nano-grained copper [21], nano-grained gold [25,26], nano-grained gold-copper alloys [22], amorphous nickel-phosphorus alloy [23], and single crystalline nickel-cobalt alloys [28] have been reported in previous studies. On the other hand, there is still very limited reporting on micro-mechanical properties of polycrystalline nickel-cobalt alloys.…”