Fabrication of Micro Spur Gear in Nano Grained Al Alloy
In present work, manufacturing technologies of micro parts by micro forging and pressing were studied using strain softening phenomenon in nano grained Al-1.5mass%Mg alloy. During compressive test at 300, the Al alloy showed stain softening phenomenon by grain boundary sliding regardless of strain rate. Micro spur gear with ten teeth (height of 200 μm and pitch of 250 μm) was fabricated with sound shape by micro forging. During micro forging, increase of applied stress induced by friction between material and die surface was effectively compensated by decrease of stress by strain softening behavior and as a result, flow stress increased only about 50 MPa more than that in compressive test. However, in micro pressing, flow of material did not occurred sufficiently to fill die and the resultant shape of gear was very poor.
Duk Yong Yoon, Suk-Joong L. Kang, Kwang Yong Eun and Yong-Seog Kim
W. S. Lee et al., "Fabrication of Micro Spur Gear in Nano Grained Al Alloy", Materials Science Forum, Vols. 534-536, pp. 393-396, 2007