https://doi.org/10.1016/j.ultsonch.2022.105966

Ultrasound assisted aqueous two-phase extraction of polysaccharides from Cornus officinalis fruit: Modeling, optimization, purification, and characterization

In the present study, bobbin tool friction stir processing (BT-FSP) with a cylindrical pin was utilized to produce bulk processed AA1050 and AA1050/6.5 vol% silica fume (SF) composite at a rotation speed of 600 rpm using two travel speeds of 100 and 200 mm/min. The BT-FSP temperature was measured for both processed materials. Phase composition, relative density, macrostructure, hardness, ultimate tensile strength, and compressive strength were examined for the AA1050 base material, processed AA1050 and AA1050/SF composite. The results showed that the temperature of BT-FSP was increased with SF addition. The addition of fine SF resulted in a small crystallite size compared to the AA1050 BM and the processed AA1050. Moreover, the SF addition to the AA1050 matrix improved mechanical properties in terms of hardness, ultimate tensile strength, and compressive strength compared to AA1050 BM and processed AA1050. The bulk AA1050/6.5 vol% nano SF composite produced at 600 rpm and 200 mm/min showed remarkable enhancements in properties compared to AA1050 parent material; i.e. 50% in hardness, 11% in compressive strength, and 40% in ultimate tensile strength. 

Production of AA1050/silica fume composite by bobbin tool-friction stir processing: Microstructure, composition and mechanical properties

Effect of single and double pass friction stir processing on microhardness and wear properties of AA5083/Al2O3 surface composites

This study investigated the microstructure, mechanical characteristics, and in vitro corrosion behavior of gradient AZ91-bioactive glass composite wire fabricated by friction stir back extrusion. The results showed that by decreasing the extrusion speed from 40 to 20 mm/min, the distribution factor of bioactive glass increased from 0.31 ± 0.04–0.45 ± 0.07, and more homogenous grain size was formed at the surface and center zone of the composite wire. Under the influence of heat and plastic deformation during friction stir back extrusion, despite the formation of the β-phase in separate islands, the α + β eutectic phase was also formed in the composite wire. In composite wire processed with a rotational speed of 800 rpm and extrusion speed of 20 mm/min, a gradient distribution of bioactive glass was formed in the cross section of the wire. Compared to an as-cast AZ91 alloy, friction stir back extrusion conducted at a rotational speed of 800 rpm and an extrusion speed of 20 mm/min resulted in a 44% increase in corrosion resistance in simulated body fluid (SBF). 

Fabrication of new gradient AZ91-bioactive glass composite using friction stir back extrusion

This paper deals with modeling, discretization, and numerical analysis of the two-way fluid-structure interaction between a fishing wobbler and a water stream. The structural domain is an assembly of several bodies that have multiple mutual structure-to-structure interactions. These interactions are mostly nonlinear contacts that significantly influence the time step used in simulations. As a result of these nonlinearities, the numerical solving of such a model requires significant computer resources and a long computational time. The paper also presents the creation and numerical simplifications of the model. However, the model remains very realistic. It is concluded that solving the structural domain in a model that retains the interaction between solid bodies is more computationally sensitive and more demanding than solving the fluid domain.

http://casopisi.junis.ni.ac.rs/index.php/FUMechEng/article/download/6110/3513

Numerical simulation of fluid-structure interaction between fishing wobbler and water

Purpose




The purpose of this paper is to manufacture an aluminium square cross-sectional bar by using conventional lathe machine from aluminium scraps through friction stir back extrusion (FSBE) process and study the viability of the process to produce the square bar.




Design/methodology/approach




The important tasks involved in this work are as follows: designing and manufacturing the chamber and plunger components used for experimental work, experimentally studying the thermo-mechanical progression of FSBE process on adapted conventional lathe machine and analyzing the relation between controlled parameter (like rotational speed and consolidation time) and response parameter (like extrusion time, extrusion rate, grain structure and hardness).




Findings




Preliminary results show that increasing or decreasing rotational speeds results in defects. Cold crack and twisting defect were shown on square bar fabricated using low rotational speed, and hot crack defects were observed on surface of the bars produced by higher rotational speed. The manufactured square bars were tested using optical microscope and Vickers hardness tester. Microstructural studies reveal that initial grains of aluminium wire undergo significant refinement and result in equiaxed and recrystallized grains in the square bar fabricated through FSBE method. The hardness tests show almost even distribution of hardness in the specimen, but hardness was lower than parent aluminium; in comparison, uneven distribution of hardness was seen in parent aluminium.




Originality/value




FSBE process is the new method to produce the bars and rods with better mechanical properties. The ambition of this work is to convert the existing scrap materials to useful products. Based on the literature review, the work has planned to perform extrusion process with the minimum effort and limited sources. In this manner, the work is highly original and under scientific mandate.

Manufacturing and mechanical characterization of square bar made of aluminium scraps through friction stir back extrusion process

Friction stir processing (FSP) is overviewed with the process variables, along with the thermal aspect of different metals.,With its inbuilt advantages, FSP is used to reduce the failure in the structural integrity of the body panels of automobiles, airplanes and lashing rails. FSP has excellent process ability and surface treatability with good corrosion resistance and high strength at elevated temperatures. Process parameters such as rotation speed of the tool, traverse speed, tool tilt angle, groove design, volume fraction and increase in number of tool passes should be considered for generating a processed and defect-free surface of the workpiece.,FSP process is used for modifying the surface by reinforcement of composites to improve the mechanical properties and results in the ultrafine grain refinement of microstructure. FSP uses the frictional heat and mechanical deformation for achieving the maximum performance using the low-cost tool; the production time is also very less.,100

Surface development by reinforcing nano-composites during friction stir processing – a review

Friction stir back extrusion (FSBE) is a novel and an efficient method of manufacturing sounded products by using specialized tool in one step (without melting of scrap). It can be saved about 40% of material, 26–31% of energy consumption, and 16–60% of labor costs compared with conventional extrusion. The main aim of this study is fabrication of hexagonal bar from aluminum alloy scrap by FSBE. The material used for this study is AA6063 as a scrap and H-13 tool steel as a die. Considered parameters were chamber rotational speed and vertical die transverse speed as major parameter on conventional milling machine. This work has proved the feasibility to extrude hexagonal-shaped bar by using FSBE by fixed die and rotates chamber. So far, none of the researchers carried out experiment by fixed die and rotate chamber in FSBE, and also no one applied FSBE to produce other than circular shape. Aluminum hexagonal-shaped bar is used as a supporter in medical and marine industry, as a raw material to the mass production of hexagonal head aluminum nut and bolt, Allen wrenches, etc. Extruded bar was defect-free, non-blurred grain boundary, and clear surface than the base material. The result showed that the compression strength of extruded sample was higher than the base material. The optimum rotational speed of chamber to produce hexagonal bar with the minimum twist angle is 250 rpm and transverse speed 6.25 mm/min. If the rotational speed increases, twist angle also increased.

Fabrication of Hexagonal Bar from Aluminum Alloy AA6063 Scrap by Frictional Stir Back Extrusion on Milling Machine

Study of Damage Mechanism on OMT Nanoclay Polymer Hybrid Sandwich Laminates

The fabrication and mechanical performance of Al-Mg-Si alloy matrix composites reinforced with silicon carbide (SiC) and bagasse fly-ash has been explored in this work. The fabrication and experimental investigation of mechanical properties of aluminium matrix (Al/SiC) composite with and without addition of bagasse fly-ash by varying wt% of reinforcements were investigated. Chemical composition of reinforcement, weighted required amount of matrix and reinforcements, powder mixing, stirring the slurry at 500 rpm speed and 5–10 min were the parameters used to develop the Al/SiC-bagasse fly-ash hybrid composite. Bagasse fly-ash particulates added with 7.5, 10, and 12 wt% SiC were utilized to prepare 10 and 12 wt% of the reinforcing phase with Al-Mg-Si alloy as matrix using stir casting method. The cast samples were machined for evaluating the properties by performing tensile testing, compression strength testing, and micro-hardness measurement. The results disclosed that the hardness of the hybrid composites increased with increase in bagasse fly-ash content with a maximum increment of 17% observed for the Al6063-7.5% SiC-10% bagasse ash composition (in comparison with the Al-10 wt% SiC-7.5 fly-ash reinforced composition). Tensile strength reduced of maximum value of 90–68 MPa at 7.5 SiC-7.5 bagasse ash compositions.

Perumalla Janaki Ramulu

Papers

Manufacturing and mechanical characterization of square bar made of aluminium scraps through friction stir back extrusion process

Surface development by reinforcing nano-composites during friction stir processing – a review

Fabrication of Hexagonal Bar from Aluminum Alloy AA6063 Scrap by Frictional Stir Back Extrusion on Milling Machine

Study of Damage Mechanism on OMT Nanoclay Polymer Hybrid Sandwich Laminates

Fabrication, Characterization and Evaluation of Mechanical Properties of Aluminium Hybrid Matrix Composite (Al6063/SiC-Bagasse Fly-Ash)