Brittle Fracture of Electrodeposited Gold Observed by Micro-Compression

抄録

Micro-compression tests were conducted to evaluate micro-mechanical properties of electrodeposited gold. The gold film was electrodeposited on a platinum substrate with a thickness of 40 μm. The gold film was found to be composed of columnar textures along the film growth direction. Two sizes (10 × 10 × 20 μm³ and 20 × 20 × 40 μm³) of micro-pillars with a square cross-section and the long-side parallel to the Pt/Au interface were fabricated by focused ion beam. From the micro-compression tests, brittle fracture was observed. Both of the micro-pillars showed a high compressive strength of about 600 MPa, which are much higher than the strength of the bulk gold. Grain size of the gold film was estimated to be 14.7 nm, which is believed to be the main factor giving the high compressive strength. The strength of the larger micro-pillar was slightly lower than that of the smaller micro-pillar. The results confirmed presence of the size effect in these specimens.