scholarly journals Proposal of Method of Removal of Mould Material from the Fine Structure of Metallic Foams used as Filters

2014 ◽  
Vol 59 (2) ◽  
pp. 727-730 ◽  
Author(s):  
I. Kroupová ◽  
V. Bednářová ◽  
T. Elbel ◽  
F. Radkovský
Keyword(s):  
Fine Structure ◽  
Automotive Industry ◽  
Metallic Foam ◽  
Metallic Materials ◽  
Metallic Foams ◽  
Ongoing Research ◽  
Polymeric Foam ◽  
Mould Material ◽  
Main Disadvantage ◽  
Metal Materials

Abstract Metallic foams are materials that are subject of an ongoing research with the broad applicability in many different areas (e.g. automotive industry, building industry, medicine, etc.). These metal materials contain in their structure artificially created pores. These pores give them specific properties, such as: large rigidity at low density, high thermal conductivity, capability to absorb energy, etc. Since the discovery of porous metallic materials numerous methods of production have been developed. The aim of the paper is to introduce effective casting methods of manufacturing of metallic foams, namely cast metal filters from the aluminum alloy. Research deals with investment casting with use of pattern made of polymeric foam, which is used for production of metallic foam with open pores. The main disadvantage of this procedure consists in removing the mould material without damaging the fine structure of the cast filter. Plaster is used as the mould material and the most important result of this paper is the presentation of the effective procedure of plaster removal from the porous structure of cast filters.

scholarly journals Manufacturing of Cast Metal Foams with Irregular Cell Structure

2015 ◽  
Vol 15 (2) ◽  
pp. 55-58 ◽  
Author(s):  
I. Kroupová ◽  
F. Radkovský ◽  
P. Lichý ◽  
V. Bednářová
Keyword(s):  
Automotive Industry ◽  
Cell Structure ◽  
Building Industry ◽  
Metallic Materials ◽  
Metallic Foams ◽  
Experimental Part ◽  
Casting Technology ◽  
Irregular Cell ◽  
Nonferrous Alloys ◽  
Infiltration Method

Abstract Metallic foams are materials of which the research is still on-going, with the broad applicability in many different areas (e.g. automotive industry, building industry, medicine, etc.). These metallic materials have specific properties, such as large rigidity at low density, high thermal conductivity, capability to absorb energy, etc. The work is focused on the preparation of these materials using conventional casting technology (infiltration method), which ensures rapid and economically feasible method for production of shaped components. In the experimental part we studied conditions of casting of metallic foams with open pores and irregular cell structure made of ferrous and nonferrous alloys by use of various types of filler material (precursors).

A Coupled Temperature-Displacement Numerical Analysis of Hydraulic Press Workspace

2016 ◽  
Author(s):  
Jakub Jirasko ◽  
Antonin Max ◽  
Radek Kottner
Keyword(s):  
Numerical Analysis ◽  
Computational Model ◽  
Automotive Industry ◽  
Elevated Temperatures ◽  
Compressive Force ◽  
Hydraulic Press ◽  
Metallic Materials ◽  
Pressing Force ◽  
Stress Criterion ◽  
The Press

The analysis is performed on a hydraulic press which is intended for use in the automotive industry and is a part of a production line. The final phase of manufacture of interior and acoustic parts takes place in this press. These interior and acoustic parts are made of sandwich fabric which is inserted into the heated mould of the press and by treatment with a defined pressure (or, more precisely, a defined compression) and temperature, it is formed into its final shape. This press has a frame with four columns and it is not preloaded. Two double acting hydraulic cylinders placed on an upper cross beam exert the compressive force. Due to continuously increasing demands on the accuracy and quality of products not only in the automotive industry, it is necessary to ensure compliance with the accuracy of certain values of machine operation. Especially in this case, the value of accuracy substantially depends on the clamping plates of the press, for which a certain value of flatness is required, both at room temperature and at elevated temperatures. To achieve this accuracy, it is necessary to guarantee sufficient stiffness of the machine to resist the pressing force with the smallest deformation possible. Another crucial factor affecting the accuracy of the machine is heating of the heated clamping plates. Unequal heating of parts of the frame causes additional deformation that has to be quantified and eliminated. The main aim was to verify the design of the press by numerical computation and gather knowledge for modifying the topological design of the press so that it fulfils the required customer parameters of flatness and parallelism for different types of loading. A computational model of the press was created for the numerical solution of a coupled temperature-displacement numerical analysis. The analysis was performed using the finite element method in Abaqus software. The press is symmetrical in two orthogonal planes and the load of the press is considered to be centric. On the basis of these two factors it was possible to carry out the analysis by considering only a quarter of the press. The analysis was used to investigate the effects of static and combined loads from the pressing force and heat on the press. The influence of a cooling circuit located in the press frame for the reduction of frame deformation (and deformation of clamping plates) was investigated. Contacts were defined among individual parts to ensure the computational model had characteristics as close as possible to the real press. The analysis was solved as stationary, on the basis that the cooling of the tool between individual pressing cycles is negligible. The insulating plates are made of a particulate composite material which was considered to have isotropic properties depending on the temperature. For strength evaluation of composite materials all individual components of the stress tensor were examined according to the maximum stress criterion. Hook’s law was considered to be valid for the metallic materials. Von Mises criterion was used to evaluate the strength of the metallic materials. The geometry of the press was discretized using 3D linear thermally coupled brick elements with 8 nodes and full integration (C3D8T). There were approximately 174,000 elements in total. Design procedures for designing a press frame with higher work accuracy (flatness) were proposed with the example of the simplified model of the press table. With these methods it is possible to achieve times higher accuracy than is achieved with conventional method.

Production Techniques of Metallic Foams in Lightweight Materials

2022 ◽  
pp. 153-175
Author(s):  
Nuray Beköz Üllen ◽  
Gizem Karabulut
Keyword(s):  
Physical State ◽  
Metallic Foam ◽  
Metallic Foams ◽  
Production Technique ◽  
Lightweight Materials ◽  
Production Methods ◽  
Ionic State ◽  
Production Techniques ◽  
State Production ◽  
Usage Area

Lightweight materials were needed in many different areas, especially in order to reduce the required energy in areas such as automotive and aerospace industries. Metallic foams attract attention in lightweight material applications due to their unique properties. The pores in its structure provide advantages in many applications, both structural and functional by promising both ultra-lightweight construction, energy absorption, and damping insulation. Production techniques of metallic foams can generally be classified as liquid, solid, gas, and ionic state production according to the physical state of the metal at the beginning of the process. The production technique should be chosen according to the usage area and desired properties of the metallic foam and the suitability in terms of cost and sustainability of production. For this reason, the details of the production techniques should be known and the products that can be obtained and their properties should be understood. In this respect, this chapter emphasizes the production methods from past to present.

Mesoscopic investigation of layered graded metallic foams under dynamic compaction

2018 ◽  
Vol 21 (14) ◽  
pp. 2081-2098 ◽  
Author(s):  
Jinhua Zhang ◽  
Yadong Zhang ◽  
Junyu Fan ◽  
Qin Fang ◽  
Yuan Long
Keyword(s):  
Impact Loading ◽  
Dynamic Properties ◽  
Three Dimensional ◽  
Metallic Foam ◽  
Layer By Layer ◽  
Metallic Foams ◽  
Mesoscopic Model ◽  
Layer Arrangement ◽  
Computed Tomography Images ◽  
Closed Cell

This article is aimed to reveal the dynamic response of layered graded metallic foam under impact loading using a three-dimensional mesoscopic model. First, a mesoscopic model for closed-cell metallic foam is proposed based on the X-ray computed tomography images. Second, a numerical analysis approach is presented and validated with test data. Third, it studies the dynamic behavior of the layered graded metallic foam under impact loading numerically. The metallic foam specimen is composed layer by layer. The porosity, which is a fraction of the voids volume over the total volume, is different with each other for the layers. Simulations are conducted to the specimen with increasing and decreasing porosity arrangement. Results show that the layer arrangement is critical to the dynamic properties. The mesoscopic deformation of cell walls and the energy absorption capability are also affected significantly. This article gives insights into the mechanical properties and mesoscopic deformation of layered graded metallic foam.

scholarly journals Surface Modifications of Biodegradable Metallic Foams for Medical Applications

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 819
Author(s):  
Renáta Oriňaková ◽  
Radka Gorejová ◽  
Zuzana Orságová Králová ◽  
Andrej Oriňak
Keyword(s):  
Bone Tissue ◽  
Surface Modifications ◽  
Metallic Foam ◽  
Future Research ◽  
Medical Applications ◽  
Metallic Foams ◽  
Preparation Methods ◽  
Processing Technologies ◽  
Metallic Biomaterials ◽  
Bonding Properties

Significant progress was achieved presently in the development of metallic foam-like materials improved by biocompatible coatings. Material properties of the iron, magnesium, zinc, and their alloys are promising for their uses in medical applications, especially for orthopedic and bone tissue purposes. Current processing technologies and a variety of modifications of the surface and composition facilitate the design of adjusted medical devices with desirable mechanical, morphological, and functional properties. This article reviews the recent progress in the design of advanced degradable metallic biomaterials perfected by different coatings: polymer, inorganic ceramic, and metallic. Appropriate coating of metallic foams could improve the biocompatibility, osteogenesis, and bone tissue-bonding properties. In this paper, a comprehensive review of different coating types used for the enhancement of one or several properties of biodegradable porous implants is given. An outline of the conventional preparation methods of metallic foams and a brief overview of different alloys for medical applications are also provided. In addition, current challenges and future research directions of processing and surface modifications of biodegradable metallic foams for medical applications are suggested.

Corrosion and Protection of Magnesium Alloys

2015 ◽  
Vol 1120-1121 ◽  
pp. 1078-1082 ◽  
Author(s):  
Yang Yang Lv ◽  
Ling Feng Zhang
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Magnesium Alloys ◽  
Automotive Industry ◽  
Physical And Mechanical Properties ◽  
Current Status ◽  
Strain Rates ◽  
Metallic Materials ◽  
Az91 Magnesium Alloy ◽  
Az91 Magnesium

Magnesium alloy as a green material in the 21st century, because of its excellent physical and mechanical properties of metallic materials as an ideal in the automotive industry, electronic industry and aviation, aerospace and other industries[1]. However, poor corrosion resistance of magnesium alloys become an important issue hinder application of magnesium alloys[2]. So magnesium alloy corrosion problems and the current status of research paper reviews several magnesium alloy protection methods at home and abroad, and also highlighted with our latest laser shock (LSP) study of AZ91 magnesium alloy at high strain rates of corrosion resistance results.

Processing of Closed-Cell Magnesium Foams

2007 ◽  
Vol 539-543 ◽  
pp. 1839-1844 ◽  
Author(s):  
Koichi Kitazono ◽  
Yusuke Kikuchi ◽  
Eiichi Sato ◽  
Kazuhiko Kuribayashi
Keyword(s):  
Cell Morphology ◽  
Solidus Temperature ◽  
Bonding Process ◽  
Metallic Materials ◽  
Metallic Foams ◽  
Magnesium Matrix Composite ◽  
Magnesium Matrix ◽  
Acoustic Damping ◽  
Blowing Agent ◽  
Closed Cell

Lightweight metallic foams are an attractive material having excellent energy absorption and acoustic damping. The density of magnesium is the smallest among structural metallic materials, and is about two third of the density of aluminum. It is, however, difficult to produce magnesium foams by conventional process because of their chemical activity. This paper provides a novel manufacturing process of magnesium foams. Accumulative diffusion-bonding process can produce a magnesium matrix composite (preform) containing titanium hydride (TiH2) particles as a blowing agent. Foaming tests of three magnesium alloys, AZ31, AZ91 and ZA146, revealed that low solidus temperature is effective to produce fine cell morphology. Chemical composition is significantly important to optimize the cell morphology of magnesium foams.

Modeling of the Behavior of an Aluminum Metallic Foam by Both FEM and Experimental Results

2013 ◽  
Vol 773-774 ◽  
pp. 478-487
Author(s):  
Juan Pablo Fuertes ◽  
Rodrigo Luri ◽  
Javier León ◽  
Daniel Salcedo ◽  
Ignacio Puertas ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Flow Stress ◽  
Material Flow ◽  
Aluminum Foam ◽  
Research Work ◽  
Physical And Mechanical Properties ◽  
Metallic Foam ◽  
Low Density ◽  
Metallic Materials ◽  
Aluminum Foams

Aluminum foams are porous metallic materials which possess an outstanding combination of physical and mechanical properties such as: a high rigidity with a very low density. In this present research work, a study on the upsetting of an aluminum foam (with a density = 0.73 g/cm3) is carried out by employing different compression velocity values. From the results obtained, it is possible to determine the material flow stress for its subsequent use in finite element simulations (FEM). Once the material flow stress has been determined, it will be employed in order to analyze the conformability of several parts by FEM.

Study of the dynamic hardness of structural metal materials

2020 ◽  
Vol 86 (1) ◽  
pp. 57-61
Author(s):  
Aleksandr V. Ilinskiy ◽  
Alexey V. Fedorov ◽  
Ksenia A. Stepanova ◽  
Igor U. Kinzhagulov ◽  
Igor O. Krasnov
Keyword(s):  
Comparative Analysis ◽  
Standard Deviation ◽  
Energy Approach ◽  
Metallic Materials ◽  
Sample Standard Deviation ◽  
Dynamic Indentation ◽  
Dynamic Hardness ◽  
Structural Metal ◽  
Metal Materials ◽  
Hardness Values

The mechanical properties of structural metallic materials are the most important indicators of their quality. Different methods (i.e., the methods of Shore, Brinell, Rockwell, Leeb, Vickers, method of instrumental indentation, and others) are currently used for determination of the hardness — one of the most important mechanical characteristics of structural metal materials. Among them is the method of dynamic indentation first developed at the Institute of Applied Physics of the National Academy of Sciences of Belarus. With the goal of further developing of the method of dynamic indentation, we propose the procedures aimed at increasing the accuracy of assessing the hardness of structural metallic materials: parameters of the contact interaction of the indenter with the sample material (Brinell hardness values) were measured using a dynamic indentation (DI) device; the values of surface and volumetric dynamic hardness were calculated taking into account the characteristics obtained using a DI device; a comparative analysis of hardness estimates obtained by different approaches was carried out. As a result of the comparative analysis of the methods, as well as their experimental testing, it was shown that an increase in the accuracy of hardness assessment can be achieved by using the «energy» approach based on assessing the ratio of the total work to the volume of the recovered indentation upon dynamic indentation of structural metal materials. The use of the «energy» approach provided obtaining the sample standard deviation of the volumetric dynamic hardness values, which, in turn, was significantly lower than the sample standard deviation of the surface dynamic hardness values and data of the dynamic indentation device, which directly affects an increase in the accuracy of hardness estimation during dynamic indentation of structural metal materials. Proceeding from the «energy» approach, a new algorithm for processing the initial signal is proposed when the dynamic hardness is determined using a dynamic indentation device.

Sign in / Sign up

Export Citation Format

Share Document