An introduction to heat transfer

Optimization Techniques with FORTRAN

Welding and Joining of NiTi Shape Memory Alloys: A Review

The effect of tool traverse and rotation speeds on the residual stresses are quantified for welds between non-age-hardening AA5083 and age-hardening AA6082 and compared to single alloy joints made from each of the two constituents. The residual stresses have been characterised non-destructively by neutron diffraction and synchrotron X-ray diffraction. The region around the weld line was characterised by significant tensile residual stress fields which are balanced by compressive stresses in the parent material. The rotation speed of the tool has been found to have a substantially greater influence than the transverse speed on the properties and residual stresses in the welds, particularly on the AA5083 side where the location of the peak stress moves from the stir zone to beyond the edge of the tool shoulder. The changes in residual stress are related to microstructural and hardness changes as determined in a previous study [1,2]. In particular the larger stresses under the weld tool on the AA5083 side compared to the AA6082 side are related to a transient reduction in yield stress due to dissolution of the hardening precipitates during welding prior to natural aging after welding.

Dissimilar friction stir welds in AA5083-AA6082: The effect of process parameters on residual stress

The sustainability of manufacturing processes is one of important issues in the aspect of green technology to deal with global warming and finite resources. Direct metal additive manufacturing (DMAM) processes are widely used to fabricate three-dimensional metallic parts with geometrical complexity through layer-by-layer deposition of metallic materials. The layer-by-layer deposition characteristics of the DMAM process can easily create a freeform geometry with characteristic shapes and a heterogeneous structure with different materials unlike the conventional manufacturing (CM) process. The inherent characteristics and the promising merits of the DMAM can provide a solution to improve the sustainability of the manufacturing process. This paper reviewed the DMAM processes and their sustainable applications for green technology. Principles and characteristics of the DMAM processes were investigated. The state-of-the art and important issues related to sustainable applications of DMAM processes were discussed. Finally, significant opportunities and future research issues of the DMAM process were discussed from the viewpoint of the improvement of sustainability.

Direct metal additive manufacturing processes and their sustainable applications for green technology: A review

Investigation of residual stress and post weld heat treatment of multi-pass welds by finite element method and experiments

Numerical analysis of secondary cooling and bulging in the continuous casting of slabs

Microstructure prediction of Nimonic 80A for large exhaust valve during hot closed die forging

Efficient forging process to improve the closing effect of the inner void on an ultra-large ingot

A study on the hot-deformation behavior and dynamic recrystallization of Al-5 wt.%Mg alloy

Jong-Rae Cho

Papers

Investigation of residual stress and post weld heat treatment of multi-pass welds by finite element method and experiments

Numerical analysis of secondary cooling and bulging in the continuous casting of slabs

Microstructure prediction of Nimonic 80A for large exhaust valve during hot closed die forging

Efficient forging process to improve the closing effect of the inner void on an ultra-large ingot

A study on the hot-deformation behavior and dynamic recrystallization of Al-5 wt.%Mg alloy