Integral Channels in Metal Components and Fabrication Thereof

An internal channel in a metal body for use in applications where internal fluid flow within a metal body is desired, as in a heat exchanger. The internal channel is formed in the metal body by frictionally stirring with a pin plunged into the metal body, and traversing the metal body with the pin

Integral Channels in Metal Components and Fabrication Thereof

An internal channel in a metal body for use in applications where internal fluid flow within a metal body is desired, as in a heat exchanger. The internal channel is formed in the metal body by frictionally stirring with a pin plunged into the metal body, and traversing the metal body with the pin

Superplastic Forming of Micro Components

A method for forming a miniaturized shaped component. Bulk superplastic material is contacted with a flat rotating surface of a rotating tool to frictionally heat the bulk superplastic material with the bulk superplastic material positioned between the flat rotating surface of the tool and a micro fabricated tool die. The bulk superplastic material is forced into the microfabricated die once the bulk superplastic material is heated to a temperature between a glass transition temperature and a crystallization temperature

Evaluation of Microstructure and Superplasticity in Friction Stir Processed 5083 Al Alloy

Friction stir processing (FSP) has been developed as a potential grain refinement technique. In the current study, a commercial 5083 Al alloy was friction stir processed with three combinations of FSP parameters. Fine-grained microstructures with average grain sizes of 3.5-8.5 µm were obtained. Tensile tests revealed that the maximum ductility of 590 was achieved at a strain rate of 3 x 10-3 s-1 and 530 °C in the 6.5-µm grain size FSP material, whereas for the material with 8.5-µm grain size, maximum ductility of 575 was achieved at a strain rate of 3 x 10-4 s-1 and 490 °C. The deformation mechanisms for both the materials were grain boundary sliding (m ~0.5) However, the 3.5-µm grain size material showed maximum ductility of 315% at 10-2 s-1 and 430 °C. The flow mechanism was solute-drag dislocation glide (m ~0.33) This study indicated that establishing a processing window is crucial for obtaining optimized microstructure for optimum superplasticity

Metal Superplasticity Enhancement and Forming Process

A shaped metallic component is formed by friction stirring at least a segment of a single piece of bulk metal to impart superplasticity thereto and thereby yield a single superplastic metal blank from the single piece of bulk metal. The metal blank is then deformed by a metal deformation process such as forging, rolling, drawing, bending, extruding, gas forming, punching, and stamping

Elevated Temperature Deformation Behavior of Nanostructured Al-Ni-Gd-Fe Alloys

The elevated temperature deformation behavior of nanostructured Al89Ni3Gd7Fe1 alloy was characterized. Tensile strength was 760 MPa at 373 K. Ductility of the alloy increases with increasing strain rate at 573 K. At high temperatures (623-673 K), the operative deformation mechanism is dislocation-climb controlled

High Strain Rate Superplasticity in Microcrystalline and Nanocrystalline Materials

Superplasticity has evolved to become a significant industrial forming process. The phenomenon of superplasticity is explored at high strain rates where it is economically more attractive. True tensile superplasticity has been demonstrated in nanocrystalline materials. The difference in the details of superplasticity between the nanocrystalline and microcrystalline state is emphasised

Preparation of a ZrO₂-Al₂O₃ Nanocomposite by High-Pressure Sintering of Spray-Pyrolyzed Powders

ZrO2-Al2O3 powders were synthesized by spray pyrolysis. These powders were sintered at 1 GPa in the temperature range of 700Ç1100 ÉC. The microstructural evolution and densification are reported in this paper. The application of 1 GPa pressure lowers the crystallization temperature from ~850 to 700 ÉC. Similarly, the transformation temperature under 1 GPa pressure for \u3c\u3eg ê a Al2O3 reduces from ~1100 to 700Ç800 ÉC range, and that for t \u3c\u3eê m ZrO2 reduces from ~1050 to 700Ç800 ÉC range. It was possible to ob-tain highly-dense nanocrystalline ZrO2-Al2O3 composite at temperatures as low as 700 ÉC. The effect of high pressure on nucleation and transformation of phases is discussed

Evolution of microstructure and mechanical properties in gas tungsten arc welded dual-phase Fe50Mn30Co10Cr10 high entropy alloy

Funding Information: JPO acknowledges the funding by national funds from FCT - Fundação para a Ciência e a Tecnologia , I.P., in the scope of the projects LA/P/0037/2020 , UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication – i3N. Funding Information: JGL, JS and JPO acknowledge Fundação para a Ciência e a Tecnologia ( FCT - MCTES ) for its financial support via the project UID/00667/2020 (UNIDEMI). Funding Information: JS acknowledges the China Scholarship Council for funding the Ph.D. grant (CSC NO. 201808320394 ). Funding Information: JGL acknowledges FCT – MCTES for funding the Ph.D. grant 2020.07350. BD . Publisher Copyright: © 2023 The AuthorsIn recent years, high entropy alloys (HEAs) have been shown to be promising alternatives to common engineering alloys, depending on their composition and thermomechanical processing. Up to now, several works aimed at improving the mechanical properties and discovering different HEAs given the extremely large compositional possibilities made available by the multicomponent approach associated to these materials. Their processability, however, is an important topic that must be studied. Welding is a key manufacturing technique that will eventually be applied to HEAs. Thus, there is a need to evaluate the microstructure and property changes induced by the weld thermal cycles, to assess the suitability of certain welding process/HEAs combinations for possible industrial applications. In the present work, Gas Tungsten Arc Welding (GTAW) was used to achieve defect-free joints based on a novel transformation induced plasticity (TRIP) Fe50Mn30Co10Cr10 HEA. The microstructure and mechanical behavior of the joints were assessed by means of optical and electron microscopy, synchrotron X-ray diffraction, thermodynamical calculations, microhardness mapping and tensile testing. Overall, an excellent mechanical performance was obtained on the resulting joints, opening the door for their adoption in real-life applications.publishersversionpublishe