Powder Injection Molding of Multimaterial Parts – Self Lubricating Steel
Combined with Plain-Carbon Steel
Renan Schroeder
a
, Antônio I. Ramos Filho, Cristiano Binder, Aloisio N. Klein.
Materials Laboratory (LabMat), Federal University of Santa Catarina, EMC - Bloco B, 88040-900,
Po Box 476, Florianópolis, SC, Brazil. Phone: +55 (48) 37219268 ext. 217
a
email: schroeder@emc.ufsc.br
Keywords: Multimaterial parts, Powder Injection Molding, Co-sintering, Self Lubricating Steels
Abstract. Powder Injection Molding allows processing of multifunctional parts through
combination of different materials in a single structure. This technique so-called Two Components
Powder Injection Molding has been developed some years ago and now is rapidly being considered
for many engineering applications. In this paper, some important aspects of materials selection and
processing conditions are reviewed in order to look insight of the technology. To show how
successful can be the technique, carbonyl iron feedstock was co-sintered to the recently developed
self lubricating steel, aiming at different tribological properties in each side of the final component.
Defect-free parts were obtained and the tensile resistance was in the same range of single material
parts, representing a very strong bonding interface.
Introduction
The concept of developing tailored materials for specific engineering applications is widespread
into the scientific and industrial community. More than ever researches are worried in designing
new alloys with accurate properties instead of choosing common practice materials. In this reality,
powder metallurgy appears as a very promising technique to process them, mainly because of the
ability to combine different powders to further obtain special microstructures with endowed
properties.
However, in some high technology components more than one property is required and even these
new materials do not fulfill, by themselves, the necessary functions for such an application.
Therefore, addition of an extra material using a secondary joining step, e.g. welding, is normally the
primary solution.
An idea to overcome such an extra manufacturing step is combining two different alloy powders
already during the molding step of any powder metallurgy method, like two-layer compaction, 3D-
printing, injection molding and others [1,2,3]. In that way, a multimaterial part is shaped and
sintered to reach the final and unique combination of different properties in a single structure and,
evidently, using only one manufacturing route.
The successful manufacturing of two material parts by powder metallurgy depends on some
variables related to materials and processing. Therefore, the aim of this paper is to list the very first
requirements that people need to concern when considering production of multimaterial parts by
powder metallurgy, particularly via Powder Injection Molding. To exemplify, we have processed
multimaterial samples of self lubricating steel with plain-carbon steel. These materials combination
gives low coefficient of friction and wear resistance in one side of the structure, while low cost raw
material (carbonyl iron powder) in the other side. In clear words, the layer of self lubricating steel
acts in very similar way as a coating steel.
Materials Science Forum Vols. 727-728 (2012) pp 243-247
Online available since 2012/Aug/24 at www.scientific.net
© (2012) Trans Tech Publications, Switzerland
doi:10.4028/www.scientific.net/MSF.727-728.243
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP,
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