The combined effects of grain and sample sizes on the mechanical properties and fracture modes of gold microwires

Yang, Haokun; Cao, Ke; Han, Ying; Wen, Minru; Guo, Junming; Tan, Zhi Long; Lü, Jian; Lü, Yang

doi:10.1016/j.jmst.2018.09.012

Cited by 15 publications

(2 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Brenner [6] found an inverse dependence of strength on the specimen wire diameter for α-iron and copper whiskers. The same dependence has been found for integrated circuit-connected measurements on gold micro-wires [21] as well as for thin copper wires [22] and other nickel nano-pillar [23] materials, also with consideration taken into account of the nano-polycrystal grain structures. The status of nano-polycrystal micro-pillar strength properties have been reviewed by Shahbeyk et al [24].…”

Section: Crystal (Grain) Size-dependent Strengthssupporting

confidence: 73%

Crystal Strengths at Micro- and Nano-Scale Dimensions

Armstrong

Elban

2020

Crystals

View full text Add to dashboard Cite

Higher strength levels, achieved for dimensionally-smaller micro- and nano-scale materials or material components, such as MEMS devices, are an important enabler of a broad range of present-day engineering devices and structures. Beyond such applications, there is an important effort to understand the dislocation mechanics basis for obtaining such improved strength properties. Four particular examples related to these issues are described in the present report: (1) a compilation of nano-indentation hardness measurements made on silicon crystals spanning nano- to micro-scale testing; (2) stress–strain measurements made on iron and steel materials at micro- to nano-crystal (grain size) dimensions; (3) assessment of small dislocation pile-ups relating to Griffith-type fracture stress vs. crack-size calculations for cleavage fracturing of α-iron; and (4) description of thermally-dependent strain rate sensitivities for grain size strengthening and weakening for macro- to micro- to nano-polycrystalline copper and nickel materials.

show abstract

Section: Crystal (Grain) Size-dependent Strengthssupporting

confidence: 73%

Crystal Strengths at Micro- and Nano-Scale Dimensions

Armstrong

Elban

2020

Crystals

View full text Add to dashboard Cite

show abstract

“…As a result of its excellent electrical conductivity, chemical stability, and corrosion resistance, gold is widely used as an electronic sliding contact material for high precision inertial devices, satellite slip ring brushes, robots, etc. [ 1 , 2 , 3 , 4 , 5 ]. However, the low intrinsic hardness, easy deformation, and poor elasticity of pure gold limits its application in circumstances necessitating high mechanical strength requirements [ 6 , 7 ].…”

Section: Introductionmentioning

confidence: 99%

Ultrafast Parallel Micro-Gap Resistance Welding of an AuNi9 Microwire and Au Microlayer

Zhang

Wang

et al. 2021

Micromachines

View full text Add to dashboard Cite

Welding between an AuNi9 microwire and Au microlayer is of great importance for fabricating electrical contact structures for high precision inertial devices, satellite slip ring brushes, robots, etc. In this paper, the achievement of parallel micro-gap resistance welding (PMRW) with 200-μm AuNi9 microwires on a 3-μm Au layer was presented. The study on the orthogonal design of the experiment was carried out. The effect of the process parameters (welding current, welding time, and welding pressure) was discussed in reference to the morphologies and tensile force of the joint using range analysis. It is shown that too much or too little heat input will decrease the welding performance. A group of optimized process parameters (0.275 kA welding current, 3 ms welding time, and 28.7 N welding pressure) was obtained. During the welding process, the dynamic resistance of the whole welding system was measured, which can reflect the welding quality. Finite element simulation is utilized to calculate the welding temperature. The highest temperature was located in the center area of the AuNi9 microwire, reaching 1397.2 °C, which is higher than the melting point of AuNi9. By contrast, the highest temperature for the pad was 826.47 °C (lower than the melting point of Au). Hence, under optimized process parameters, a transient interfacial reaction between the liquid AuNi9 microwire and solid Au pad occurred, and the strength of the welded joint reached 5.54 N.

show abstract