There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

An introduction to heat transfer

Interfacial characteristic and mechanical performance of maraging steel-copper functional bimetal produced by selective laser melting based hybrid manufacture

Effect of beam offset on the characteristics of copper/304stainless steel electron beam welding

Microstructure and mechanical properties of Ti–6Al–4V alloy fabricated using electron beam freeform fabrication

Study on strengthening mechanism of Ti/Cu electron beam welding

Microstructure and mechanical characterization of re-melted Ti-6Al-4V and Al-Mg-Si alloys butt weld

Friction stir welding (FWS) is regarded as a more plausible alternative to other welding methods for Al-Cu dissimilar joining. However, the structure of an FSW joint is different from others. In this study, lap joints of 6061 aluminum alloy and commercially pure copper were produced by FSW, and the effects of rotation rate on macromorphology, microstructure and mechanical properties were investigated. In addition, a fracture J integral model was used to analyze the effect of microstructure on the mechanical properties. The results revealed that the macrodefect-free joints were obtained at a feed rate of 150 mm/min and 1100 rpm and that the failure load of the joint reached as high as 4.57 kN and only reached 2.91 kN for the 900 rpm, where tunnel defects were identified. Particle-rich zones composed of Cu particles dispersed in an Al matrix, and “Flow tracks” were observed by the EDS. The J integral results showed that the microdefects on the advancing side cause serious stress concentration compared with the microdefects located on the Al-Cu interface, resulting in the fracture of the joints.

Analysis on the Fracture of Al-Cu Dissimilar Materials Friction Stir Welding Lap Joint

Zhu Jun

Papers

Effect of beam offset on the characteristics of copper/304stainless steel electron beam welding

Microstructure and mechanical properties of Ti–6Al–4V alloy fabricated using electron beam freeform fabrication

Study on strengthening mechanism of Ti/Cu electron beam welding

Microstructure and mechanical characterization of re-melted Ti-6Al-4V and Al-Mg-Si alloys butt weld

Analysis on the Fracture of Al-Cu Dissimilar Materials Friction Stir Welding Lap Joint