scholarly journals Change of Microstructure and Hardness of Duo-Casted Al3003/Al4004 Clad Material during Extrusion Process

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1648
Author(s):  
Jin-Kyung Lee ◽  
Sang-Pill Lee ◽  
Jong-Sup Lee ◽  
Sangmok Lee ◽  
Ilguk Jo ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Extrusion Process ◽  
Knoop Hardness ◽  
Casting Method ◽  
Cast Material ◽  
Metallic Inclusions ◽  
Hardness Change ◽  
Change Of Microstructure ◽  
Slight Deformation

This study was carried out to observe and measure the microstructure, distance between dendrite arms, aspect ratio, and Knoop hardness change of extruded material formed by the hydro co-extrusion of Al3003/Al4004 clad material manufactured by the duo-casting method. The specimen of duo-casted Al3003/Al4004 clad materials was circle shaped; it was composed of Al3003 (outside) and Al4004 (inside) materials. The manufacturing conditions of the hydro co-extruded specimen were 423 K temperature and 6.5 ratio of extrusion. At the interface of the duo-casted Al3003/Al4004 clad material, a non-junction at the interface and non-metallic inclusions of Si- and Mn-based oxides were observed. Al3003 exhibits equiaxed crystals; Al4004 has a casted structure with dendrites before extrusion, showed slight deformation during extrusion, and then finally exhibited completely deformed structures after extrusion. In the cast material, the distance between dendrite arms increased, and the aspect ratio of dendrites tended to decrease from the surface to the center. However, in the case of the extruded material, neither Al3003 nor Al4004 changed significantly from the surface to the inside. As extrusion progressed, the Knoop hardness value at the interface of Al3003/Al4004 increased rapidly compared with those of Al3003 and Al4004 matrixes.

Effect of Polyethylene Glycol in Nanocellulose/PLA Composites

2019 ◽  
Vol 821 ◽  
pp. 89-95
Author(s):  
Wanasorn Somphol ◽  
Thipjak Na Lampang ◽  
Paweena Prapainainar ◽  
Pongdhorn Sae-Oui ◽  
Surapich Loykulnant ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Lactic Acid ◽  
Polyethylene Glycol ◽  
Aspect Ratio ◽  
Mechanical Performance ◽  
Tensile Modulus ◽  
Poly Lactic Acid ◽  
Solvent Casting ◽  
Casting Method ◽  
Mediated Oxidation

Poly (lactic acid) or PLA was reinforced by nanocellulose and polyethylene glycol (PEG), which were introduced into PLA matrix from 0 to 3 wt.% to enhance compatibility and strength of the PLA. The nanocellulose was prepared by TEMPO-mediated oxidation from microcrystalline cellulose (MCC) powder and characterized by TEM, AFM, and XRD to reveal rod-like shaped nanocellulose with nanosized dimensions, high aspect ratio and high crystallinity. Films of nanocellulose/PEG/PLA nanocomposites were prepared by solvent casting method to evaluate the mechanical performance. It was found that the addition of PEG in nanocellulose-containing PLA films resulted in an increase in tensile modulus with only 1 wt% of PEG, where higher PEG concentrations negatively impacted the tensile strength. Furthermore, the tensile strength and modulus of nanocellulose/PEG/PLA nanocomposites were higher than the PLA/PEG composites due to the existence of nanocellulose chains. Visual traces of crazing were detailed to describe the deformation mechanism.

Deformation Behaviors of Non-Metallic Inclusion in FGH96 Superalloy during Different Plastic Processes

2012 ◽  
Vol 538-541 ◽  
pp. 1187-1191
Author(s):  
Min Cong Zhang ◽  
Chen Yi Liu ◽  
Shu Yun Wang
Keyword(s):  
Transition Zone ◽  
Extrusion Direction ◽  
Extrusion Process ◽  
Extrusion Ratio ◽  
Metallic Inclusion ◽  
Isothermal Forging ◽  
Forging Process ◽  
Discontinuous Line ◽  
Metallic Inclusions ◽  
Deformation Behaviors

The non-metallic inclusions in FGH96 superalloy during different plastic processes were studied. The results show that SiO2 react with aluminum and titanium in FGH96 superalloy and the reaction zone is formed in the interface between SiO2 and alloy, whereas Al2O3 react with no elements in FGH96 superalloy and the transition zone between them is mechanical combination during the plastic processes. In addition the sizes of non-metallic inclusions increase in the direction perpendicular to deformation during isothermal forging process. The non-metallic inclusions are pulled into a discontinuous line in extrusion direction and areas of non-metallic inclusions in each direction are constricted during extrusion process. The non-metallic inclusions of FGH96 superalloy is conditioned by the state of the as-extrusion inclusions during extrusion+isothermal forging process. In summary, extrusion process with large extrusion ratio can break the non-metallic inclusions in FGH96 alloy effectively and improve forging quality.

Mechanical Property Evaluation of Electroplated High Aspect Ratio Microstructures

1998 ◽  
Vol 518 ◽  
Author(s):  
L. S. Stephens ◽  
K.W. Kelly ◽  
E.I. Meletis ◽  
S. Simhadri
Keyword(s):  
Mechanical Properties ◽  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Mold Insert ◽  
Processing Parameters ◽  
Strength Properties ◽  
Knoop Hardness ◽  
Modulus Of Rupture ◽  
Mechanical Seal ◽  
Property Evaluation

AbstractHigh aspect ratio microstructures (HARMs) with a height of hundreds of micrometers and a width of a few tens of micrometers present high promise in a number of challenging fields. At LSU, a number of applications are being developed in which nickel HARMs are electroplated on metal surfaces (mold insert fabrication for the LIGA process, HARMs on mechanical seal faces, HARMs on heat exchange surfaces, etc.). In some of these applications, the HARMs are subjected to high stresses and the mechanical properties are particularly important. These properties can be used to adjust processing parameters to optimize properties of the HARMS.This paper presents a method for measuring the strength properties of cantilevered nickel HARMs constructed by LIGA. Experimentally measured values are reported for modulus of rupture (1280 MPa), Young's modulus (153 GPa) and Knoop hardness (500 Hk) for HARMs with an overplated base. SEM micrographs clearly indicate that failure of the beams is brittle and most frequently occurs at the interface of the beam and overplated base.

Microstructure Evolution and Mechanical Properties of Extruded Mg-Al-Zn-Sn Alloy Sheets

2017 ◽  
Vol 898 ◽  
pp. 300-304
Author(s):  
Qing Shan Yang ◽  
Wen Jun Liu ◽  
Zu Jian Yu
Keyword(s):  
Mechanical Properties ◽  
Room Temperature ◽  
Extrusion Process ◽  
Extrusion Ratio ◽  
Mg Alloy ◽  
Casting Method ◽  
Mechanical Responses ◽  
Room Temperature Ductility ◽  
Differential Speed ◽  
Scanning Electron

The microstructure and mechanical responses of the AZ31 with the addition of 1.8% Sn alloys have been studied and compared. Mg alloy sheets were prepared with metal model casting method and subsequent processes by conventional extrusion (CE) and differential speed extrusion (DSE). Mg alloys were hot extruded at 400oC with the extrusion ratio of 101:1. The microstructure of Mg alloy sheets was examined by optical microscopy (OM) and scanning electron microscope (SEM). The results indicated that the grains were dynamically recrystallized after the extrusion process. Moreover, DSE process dramatically enhanced the room temperature ductility of the extruded sheets. It was also presented that the Mg alloy processed by DSE exhibite a classical dimple structure as a result of slip accumulation and ductile tear.

scholarly journals Creep of particle and short fibre reinforced polyurethane rubber

2021 ◽  
Author(s):  
Yi Cui ◽  
Trevor William Clyne
Keyword(s):  
Aspect Ratio ◽  
Volume Fraction ◽  
Creep Behaviour ◽  
Extrusion Process ◽  
Short Fibre ◽  
Stress Strain ◽  
Eshelby Model ◽  
Model Predictions ◽  
Short Fibres ◽  
Strain Testing

AbstractTensile stress–strain testing and creep testing have been carried out on a polyurethane rubber, at three temperatures, with and without either particulate or short fibre alumina reinforcement. A previous paper reported concerning composites with particulate reinforcement and the present work is focused on the effect of the fibres. The samples were made via a blending and extrusion process that produced a certain degree of fibre alignment (along the direction of loading). Prior milling procedures were used to produce fibres with two different ranges of aspect ratio (with averages about 10 and 16). When expressed as true stress–strain relationships, all materials exhibit approximately linear responses. The dependence of stiffness on the volume fraction and aspect ratio of the reinforcement was found to conform well to the Eshelby model predictions. Moreover, the creep behaviour of all of the materials can be captured well by a Miller–Norton formulation, using the average matrix stress predicted by the Eshelby model. A striking conclusion is that it is both predicted and observed that short fibres are much more effective in reducing the creep rate than is the case with particles.

Experimental and Simulation of Friction Effects in an Open-Die Microforging/Extrusion Process

2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Ehsan Ghassemali ◽  
Ming-Jen Tan ◽  
Samuel Chao Voon Lim ◽  
Chua Beng Wah ◽  
Anders Eric Wollmar Jarfors
Keyword(s):  
Aspect Ratio ◽  
Friction Factor ◽  
Response Surface ◽  
Accurate Result ◽  
Extrusion Process ◽  
Friction Model ◽  
Anova Analysis ◽  
Whole Process ◽  
Surface Method ◽  
Frictional Condition

Friction effects during a progressive microforming process for production of micropins of various diameters were experimentally investigated and were analytically modeled, using a hybrid friction model. The response surface method and ANOVA analysis were used to generalize the findings for various pin diameters. Besides, it was shown that to get an accurate result in simulation, the friction model must be considered locally instead of a global friction model for the whole process. The effect of friction factor on the final micropart dimensions (the effect on the instantaneous location of the neutral plane) and the forming pressure were investigated. The results showed a reduction in the friction factor as die diameter increased. Following that, the optimum frictional condition to obtain the highest micropart aspect ratio was defined as the maximum friction on the interface between the die upper surface and the punch surface, together with a minimum friction inside the die orifice.

Detection and Deformation Mechanism of Non-Metallic Inclusions in FGH96 Alloy Isothermal Forging Disk

2013 ◽  
Vol 747-748 ◽  
pp. 526-534 ◽  
Author(s):  
Xiao Feng Wang ◽  
Xiao Ming Zhou ◽  
Jie Yang ◽  
Jin Wen Zou ◽  
Wu Xiang Wang
Keyword(s):  
Powder Metallurgy ◽  
Nondestructive Testing ◽  
Reaction Zone ◽  
Deformation Mechanism ◽  
Extrusion Process ◽  
Isothermal Forging ◽  
Remarkable Effect ◽  
Metallic Inclusions ◽  
Mechanical Bonding

According to the defects of powder metallurgy superalloy, especially the influence and damage of inclusions on properties of disk, the deviation between nondestructive testing and metallographic testing of inclusions in FGH96 alloy isothermal forging disk was investigated. Meanwhile, the types and deformation mechanism of inclusions were studied. The results showed that the buried depth tested by metallographic detection was less 67-180μm than nondestructive testing. The size of inclusions with metallographic detection was less about 18-50μm than nondestructive testing. The major types of inclusions in practical disk were Al2O3 and Al2O3-SiO2, the inclusions run through several grains, no matter Al2O3 or Al2O3-SiO2. The Al2O3 inclusion and matrix was purely mechanical bonding, but the Al2O3-SiO2 had reaction zone. There was remarkable effect of extrusion process on crushing and dispersing Al2O3 inclusion, but which was unremarkable for Al2O3-SiO2.

Influence of Die Angle on the Extrusion Behavior of 6061Al Matrix Composite Reinforced with SnO2-Coated Aluminum Borate Whisker

2011 ◽  
Vol 299-300 ◽  
pp. 700-703
Author(s):  
Zhi Ming Du ◽  
Pei Tang Zhao ◽  
Li Dong Wang ◽  
Wei Dong Fei
Keyword(s):  
Squeeze Casting ◽  
Average Length ◽  
Aluminum Matrix ◽  
Extrusion Process ◽  
Matrix Composites ◽  
Aluminum Borate ◽  
Casting Method ◽  
Dispersion Degree ◽  
Present Composite

The 6061Al matrix composites reinforced with SnO2-coated aluminum borate whisker were fabricated using squeeze casting method. The composite were extruded successfully at 350°Cwith different die angles. The experiment results illustrate that the die angle have important influences on the extrusion process. The surface quality of extruded composites was improved and the extrusion load was reduced with die angle increasing from 30 to 60 degree. The <111> and <100> textures for aluminum matrix were formed in all extruded composites. The dispersion degree of the <111> texture, the alignment degree and the average length of whiskers increases with die angle increasing. There is a suitable die angle for the optimization of the extrusion process of the present composite.

Preparation of Micro-Hole with Large Aspect Ratio

2017 ◽  
Vol 898 ◽  
pp. 1190-1194
Author(s):  
Ying Dong Qu ◽  
Mei Ling Jin ◽  
Jun Hua You ◽  
Rong De Li
Keyword(s):  
Carbon Fiber ◽  
Aspect Ratio ◽  
Laser Scanning ◽  
Average Diameter ◽  
Metal Wire ◽  
Large Aspect Ratio ◽  
Casting Method ◽  
Processing Technologies ◽  
Micro Hole ◽  
Traditional Processing

It was difficult to prepare micro-hole with large aspect ratio by traditional processing technologies. In order to solve the problem, a preparation was proposed. It was carried out by casting method. Carbon fiber and metal wire coated graphite paint were used as hole core respectively. And morphology and geometrical characteristic of micro-hole were observed and analyzed by scanning electron microscope and laser scanning confocal microscope. The results showed that average diameter and aspect ratio of micro-hole obtained by the group of carbon fiber hole core were about 0.2 mm and above 1700, respectively. For the other group, about 0.5 mm and 700, respectively. The micro-hole obtained by the metal wire coated graphite paint hole core was more close to circle. Its shape factor was about 0.72. The roughness of micro-hole value obtained by carbon fiber hole core was close to 3.2 μm, smaller than that of the metal wire coated graphite paint.

Microstructure Control of Porous In-Situ Synthesized Si2N2O-Si3N4 Ceramics

2007 ◽  
Vol 534-536 ◽  
pp. 1049-1052 ◽  
Author(s):  
Rajat Kanti Paul ◽  
Chi Woo Lee ◽  
Hai Doo Kim ◽  
Byong Taek Lee
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Extrusion Process ◽  
Filtration Efficiency ◽  
Carbon Addition ◽  
Microstructure Control ◽  
Sintering Additives ◽  
Network Type

Using 6wt%Y2O3-2wt%Al2O3 as sintering additives and Si as a raw powder, the continuously porous in-situ Si2N2O-Si3N4 bodies were fabricated by multi-pass extrusion process and their microstructures were investigated depending on the addition of carbon (0-9wt %) in the mixture powder. The introduction of Si2N2O fibers observed in the unidirectional continuous pores as well as in the pore-frame regions of the nitrided bodies can be an effective method in increasing the filtration efficiency. In the case of no carbon addition, the network type Si2N2O fibers with high aspect ratio appeared in the continuous pores with diameters of 150-200nm. However, in the case of 9wt% C addition, the fibers were found without any network type and had diameters of 200-250nm.

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