Aluminum alloys with nanocrystalline (NC) and ultrafine grain (UFG) size are of interest because of their strengths that are typically 30 pct greater than conventionally processed alloys of the same composition. In this study, UFG AA 5083 plate was prepared by quasi-isostatic (QI) forging of cryomilled powder, and the microstructure and mechanical behavior was investigated and compared with the...

In multi-operation forging processes, the process fault due to missing parts from dies is a critical concern. The objective of this paper is to develop an effective method for detecting missing parts by using automatic classification of tonnage signals during continuous production. In this paper, a new feature selection and hierarchical classification method is developed to improve the classifi...

The paper reports on an investigation into the various aspects of closed die cold forging of polygonal powder preforms, which have been compacted and sintered from atomized powder. It is found that for certain dimensional ratios of the preform the die pressure is minimum. An attempt has been made for the determination of the die pressures developed for given geometries of the disc during the cl...

Within the net-shape and near-net shape technology hot flashless precision forging leads to high forging accuracy of the workpiece with regard to dimensional and surface finish tolerances. The main advantages are shortened production cycles by eliminating machining operations and the saving on raw material lost during machining. By producing ready-to-mount forgings high economical and ecologica...

Mireille Akilian Mark L. Schattenburg Abstract — Many leading technologies, such as flat-panel displays and precision optics, require sheet glass with exceptional surface qualities. Commercially available sheet glass of <1-mm thickness typically has a surface warp on the order of hundreds of microns, rendering it a challenge to utilize progressively thinner sheets. A novel method of shaping ind...