Effect of powder compact density on the LIBS analysis of Ni impurities in alumina powders

2018 ◽  
Vol 148 ◽  
pp. 99-104 ◽  
Author(s):  
S.J. Pandey ◽  
R. Locke ◽  
R.M. Gaume ◽  
M. Baudelet
Keyword(s):  
Powder Compact ◽  
Compact Density

The Effect of the Green Density on the Properties of Powder Metallurgy Ti Sintered by High Frequency Induction Heating

2018 ◽  
Vol 884 ◽  
pp. 43-48 ◽  
Author(s):  
Stella Raynova ◽  
Yann Collas ◽  
Fei Yang ◽  
Leandro Bolzoni
Keyword(s):  
Tensile Strength ◽  
Powder Metallurgy ◽  
Induction Heating ◽  
High Frequency ◽  
Powder Compact ◽  
Initial Density ◽  
International Standards ◽  
Heating Rates ◽  
Compact Density ◽  
High Frequency Induction

Sintering is a vital technology used for consolidation of metal and ceramic powders. The process is generally long and energy consuming because of the way in which heat transfer happens in electrical and gas furnaces. This study focuses on optimizing the sintering process of metallic powders, in particular titanium, using high frequency induction heating as alternative sintering method. Using electromagnetic induction and the associated Eddy current effect, the heat is generated directly into the electrically conductive object. Consequently, faster heating rates and lower heat loses are achieved. The purpose of this study is to understand the effect of process parameters, such as the powder compact density, on the efficiency of the induction heating and the properties of the sintered materials. The average heating rates recorded while heating to 1300oC are in the range of 3.5o to 15.3o C per second. Significant densification and consolidation, evident by the amount of closed porosity and increase in tensile strength was found in spite of the short heating time. The results show that the powder compact density plays a crucial role on the heating efficiency as well on the properties of the sintered material such as final density, porosity distribution and tensile properties. The samples with higher initial density showed tensile strength and ductility values comparable to those of high vacuum sintered and those specified by international standards for powder metallurgy Ti products.

scholarly journals 3-Dimensional Structure-Imitation Model of Evolution of Microstructure of Powder Body During Sintering

1999 ◽  
Vol 32 (1-4) ◽  
pp. 221-233
Author(s):  
I. G. Kamenin ◽  
R. M. Kadushnikov ◽  
V. M. Alievsky ◽  
D. M. Alievsky ◽  
S. V. Somina
Keyword(s):  
Powder Compact ◽  
3D Structure ◽  
Particle Interaction ◽  
Spherical Particles ◽  
Dimensional Structure ◽  
3 Dimensional ◽  
Powder Body ◽  
Time Dependencies ◽  
Growth Laws ◽  
Evolution Of Microstructure

This paper describes a 3D structure-imitation computer model of evolution of the powder compact during sinteringand recrystallization without nucleation. At the initial stages of the evolution processes (sintering until a mosaic structure of boundaries is formed) the model particles are spheres, and two-particle interaction laws control their evolution. During sintering the degree of mutual penetration of the particles increases, regions where spherical particles are wholly facetted by contacts with neighboring particles are formed and grow. These particles are described using the formalism of Voronoi radical polyhedra, and grain growth laws govern their evolution. The model predicts the time dependencies of the following structure parameters of the polyhedra: average polyhedron size and dispersion, total surface of the facets of the polyhedra and total lenght of the edges of the polyhedra.

Creep densification of copper powder compact

1996 ◽  
Vol 38 (11) ◽  
pp. 1197-1208 ◽  
Author(s):  
M.C. Song ◽  
H.G. Kim ◽  
K.T. Kim
Keyword(s):  
Copper Powder ◽  
Powder Compact

Thermomechanical processing of a nickel-base superalloy powder compact

1983 ◽  
Vol 1 (4) ◽  
pp. 201-207 ◽  
Author(s):  
A.Y. Kandeil ◽  
J-P.A. Immarigeon ◽  
W. Wallace ◽  
M.C. de Malherbe
Keyword(s):  
Powder Compact ◽  
Thermomechanical Processing ◽  
Nickel Base Superalloy ◽  
Nickel Base ◽  
Base Superalloy ◽  
Superalloy Powder

Preparation of Titanium Alloy Parts by Powder Compact Extrusion of a Powder Mixture and Scaled up Manufacture

2016 ◽  
Vol 704 ◽  
pp. 75-84 ◽  
Author(s):  
Fei Yang ◽  
Brian Gabbitas ◽  
Ajit Pal Singh ◽  
Stella Raynova ◽  
Hui Yang Lu ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Powder Metallurgy ◽  
Titanium Alloys ◽  
Powder Mixture ◽  
Powder Compact ◽  
Blended Elemental ◽  
Pilot Plant Scale ◽  
Near Net Shape ◽  
Titanium Processing ◽  
The University

Blended Elemental Powder Metallurgy (BE-PM) is a very attractive method for producing titanium alloys, which can be near-net shape formed with compositional freedom. However, a minimization of oxygen pick-up during processing into manufactured parts is a big challenge for powder metallurgy of titanium alloys. In this paper, different approaches for preparing titanium alloy parts by powder compact extrusion with 0.05-0.1wt.% of oxygen pick-up during manufacturing are discussed. The starting materials were a powder mixture of HDH titanium powder, other elemental powders and a master alloy powder. Different titanium alloys and composites, such as Ti-6Al-4V, Ti-4Al-4Sn-4Mo-0.5Si, Ti-5Al-5V-5Mo-3Cr, and Ti-5Al-5V-5Mo-3Cr-5vol%TiB, with different profiles such as round and rectangular bars, a wedge profile, wire and tubes have been successfully manufactured on a laboratory and pilot-plant scale. Furthermore, a possible route for scaling up the titanium processing capabilities in the University of Waikato has also been discussed.

Porous Al2O3/Al catalyst supports fabricated by an Al(OH)3/Al mixture and the effect of agglomerates

2005 ◽  
Vol 20 (3) ◽  
pp. 672-679 ◽  
Author(s):  
Zhen-Yan Deng ◽  
Yoshihisa Tanaka ◽  
Yoshio Sakka ◽  
Yutaka Kagawa
Keyword(s):  
Surface Area ◽  
Compaction Pressure ◽  
High Surface ◽  
High Surface Area ◽  
Catalyst Supports ◽  
Al Content ◽  
Starting Mixture ◽  
Mechanical And Electrical Properties ◽  
Uniform Microstructure ◽  
Compact Density

Porous Al2O3/Al catalyst supports were fabricated using a mixture of Al(OH)3 and Al powders, followed by pressureless sintering at a temperature of 600 °C in vacuum. Different pressures were used to prepare green compacts. High compaction pressure led to a high surface area and good mechanical and electrical properties for the sintered specimens. However, when the Al content in the sintered specimen exceeded a definite value, high compaction pressure decreased the surface area abruptly. Scanning electron microscopy observations revealed that agglomeration in the starting mixture has a significant effect on the microstructure of the sintered specimens. High compaction pressure greatly eliminated the agglomerates and led to a uniform microstructure for the sintered specimens. However, when the Al content in the starting mixture was too high, Al particles in the compacts prepared by the high pressure were largely sintered due to the high compact density so that most of the pores were closed. The present study indicates that a suitable compaction pressure is critical to obtaining superior Al2O3/Al supports.

Sign in / Sign up

Export Citation Format

Share Document