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...

The mechanical properties of Ti49.8Ni50.2 (at %) alloy under tension at room temperature are studied in dependence on the true strain (e = 1.84–9.55) specified during isothermal multi-axial forging (abc-pressing). It was found that stress beginning pseudoyield plateau does not depend value abc-strain. after abs-pressing, already a e 1.84, yield σy 900 ± 25 MPa, which is more than twice as high ...

In this study, a cast rod is used as the material for the forging process (without extrusion). The cast forging process is used to ameliorate the coarse grains that form in the follow-up heating process of extrusion-forged materials. Infrared (IR) heating is also used for comparison with conventional heating processes. Experimental results show that the direct forging process (without extrusion...

Abstract—Closed die forging is a very complex process, and measurement of actual forces for real material is difficult and time consuming. Hence, the modelling technique has taken the advantage of carrying out the experimentation with the proper model material which needs lesser forces and relatively low temperature. The results of experiments on the model material then may be correlated with t...