<abstract xmlns="http://www.w3.org/1999/xhtml">Phosphorus as an alloy element is quite common in powder metallurgy, the contents industrially used being markedly higher than those present in wrought steels. In this study, the influence of phosphorus addition through different P carriers was investigated. PM steels of the type Fe-0.7%C-x%P (x = 0.0 … 0.8%) were manufactured by pressing and sintering in H2. It showed that Fe3P is the best phosphorus carrier, resulting in fine and regular microstructure and in high impact energy data at 0.3 … 0.45%P while red P and also Fe2P showed a tendency to agglomeration, with resulting secondary porosity. At high P levels the mechanical properties tend to drop, for the tensile strength at P > 0.60%P while for the impact energy the threshold is 0.45%P. The dimensional behaviour of Fe-C-P can be related to PM aluminium alloys, expansion by transient liquid phase being followed by shrinkage by persistent liquid phase, at least at higher temperatures. In contrast to the dimensional behaviour, degassing and reduction is hardly affected by the phosphorus content.</abstract>

Phosphorus in Sintered Steels: Effect of Phosphorus Content and P Carrier in Sintered Steel Fe-C-P

<abstract xmlns="http://www.w3.org/1999/xhtml">Phosphorus as an alloy element is quite common in powder metallurgy, the contents industrially used being markedly higher than those present in wrought steels. However, embrittlement effects are reported also for sintered steels, in part depending on the alloy elements present. In this study, the influence of phosphorus addition on the mechanical properties of PM steels alloyed with Mo, as the most common VI group element in sintered steels, was investigated. PM steels of the type Fe-x%Mo-0.7%Cy% P were manufactured with varying contents of Mo and P, respectively. It showed that P activates sintering also in these materials and enhances Mo homogenization, but there is in fact a risk of embrittlement in these steels that however strongly depends on the combination of Mo and P in the materials: If a critical level is exceeded, embrittlement is observed. At low Mo contents, higher P concentrations are acceptable and vice versa, but e.g. in a material Fe-1.5%Mo-0.7%C-0.45%P, pronounced intergranular embrittlement occurs, further enhanced by sinter hardening effects. This undesirable phenomenon is more pronounced at higher sintering temperatures and in case of faster heating/cooling; it was observed both in materials prepared from mixed and prealloyed powders, respectively. This typical intergranular failure observed with embrittled specimens, in particular after impact testing, indicates the precipitation of brittle phases at the grain boundaries, apparently when exceeding the solubility product between Mo and P.</abstract>

Phosphorus in Sintered Steels: Interaction of Phosphorus with Mo

<abstract xmlns="http://www.w3.org/1999/xhtml">This work proposes an analytical model developed from experimental data to describe the anisotropic dimensional change on sintering. Axial-symmetric iron parts differing for geometry and sintering conditions have been investigated, aiming at highlighting the influence of geometry. The specimens were measured in the green and sintered state by a coordinate measuring machine (CMM). The dimensional changes of height, external diameter and internal diameter were derived from measurement results. The anisotropy of the dimensional variations has been studied with reference to the isotropic dimensional change derived from the change in volume of the parts. The influence of geometry and sintering temperature was highlighted. To properly describe the dimensional variations in the compaction plane, the dimensional change of the external diameter versus the dimensional change of the internal one has been analysed. By means of the experimental data, a reliable analytical relationship has been found, dependent on the parts geometry. An anisotropy parameter has been identified, which allows relating the dimensional change in the compaction plane and in the axial direction to the isotropic dimensional change. This parameter depends both on geometry and on sintering conditions. By means of the anisotropy parameter an analytical model for the anisotropic behaviour has been developed.</abstract>

University of Trento – Department of Industrial Engineering – 38122 Trento,

Analytical Model of the Anisotropic Dimensional Change on Sintering of Ferrous PM Parts

<abstract xmlns="http://www.w3.org/1999/xhtml">The state of the powder surface represents one of the main interests in the whole cycle of components’ production using powder metallurgy (PM) route. Large specific surface area of the powder in combination with often alloying with oxygen sensitive elements results in oxidation of the powder surface in most of the cases. The information about surface chemistry of the powder is of vital importance for further consolidation and sintering steps. Surface sensitive analytical techniques – X-ray photoelectron spectroscopy (XPS) and high-resolution scanning electron microscopy combined with energy dispersive X-ray analysis (HR SEM+EDX) were used for surface chemical analysis of the 60Cu-40Sn bronze powder. Determination of the compositional profiles and estimation of the surface oxide layer thickness was done by altering of ion etching and XPS analysis. The results showed tin oxide enrichment and presence of copper hydroxide on the surface of the powder particles. The impurities of P, Zn and Ca were also detected on the top surface of the powder in trace amounts.</abstract>

Department of Materials and Manufacturing Technology, Chalmers University of Technology, Rännvägen 2A, 412 96 Göteborg,

3M Västervik, Folkparksvägen 31, 59383 Västervik

Copper Bronze Powder Surface Studied by XPS and HR SEM

<abstract xmlns="http://www.w3.org/1999/xhtml">Despite recent developments in sandwich panels production technology, there are some difficulties in joining core sandwiches. Liquid Phase Sintering is a conventional method to increase the density of powder metallurgy parts. In this paper, we applied LPS as a joining process between Al-foam and Al-metal by using Al-mixture powders with different compositions as the interlayer. At first stage, Al-Zn powder mixture was used and the possibility of this process was investigated. At later stages, we tried to increase the joint bonding strength with different Al-mixture powder compositions. 3-point bending test was applied and by using mathematical relations, bonding strengths were calculated. The highest bonding strength was obtained, about 9 kPa, when Al-Zn-Mg was used as the interlayer. Also energy dispersive spectrometry (EDS) was used to investigate the diffusion of additive elemental powders to Al-mixture powders.</abstract>

The Effect of Transient Liquid Phase on the Joining Process of Aluminum Foam Core Sandwiches

AHEAD OF PRINT

Volume 22 (2022): Issue 1 (December 2022)

Volume 21 (2021): Issue 2 (December 2021)

Volume 21 (2021): Issue 1 (June 2021)

Volume 20 (2020): Issue 2 (December 2020)

Volume 20 (2020): Issue 1 (June 2020)

Volume 19 (2019): Issue 2 (December 2019)

Volume 19 (2019): Issue 1 (September 2019)

Volume 18 (2018): Issue 2 (November 2018)

Volume 18 (2018): Issue 1 (June 2018)

Volume 17 (2017): Issue 2 (December 2017)

Volume 17 (2017): Issue 1 (December 2017)

Volume 16 (2016): Issue 2 (December 2016)

Volume 16 (2016): Issue 1 (October 2016)

Powder Metallurgy Progress

 POWDER METALLURGY PROGRESS – international journal of powder technology and powder-derived materials.  POWDER METALLURGY PROGRESS is an international peer-reviewed open-access materials science journal with a more than 20 years long publishing history. Since the establishment in 2001, PMP published a wide variety of quality works, focused mainly on powder metallurgy of metals, the evolution of the technology itself, preparation, properties, and applications of particular materials.  In 2021 after the celebration of the 20th anniversary of the journal, it underwent changes and transformations focused mainly on the publishing interests and scope. Now it is extended to broadly all fields of powder-derived materials and technologies.  Works from the fields of powder metallurgy, metals, alloys, ceramics, and composites, basic and applied research of materials science related to mechanical and functional properties, manufacturing, and characterization are always welcomed.  Actual Scope of the journal:    materials research such as materials physics, materials chemistry, materials engineering, traditional and advanced powder metallurgy, materials processing;  wide range of metal, ceramic and composite materials including metal matrix, ceramic matrix, polymer matrix composites, and hybrid organic-inorganic-metal-ceramic material systems, structural materials, functional materials, biomaterials, porous materials, magnetic electric and multifunctional materials such as magnetic composites, magnetoelectric, magnetocaloric, ferroelectric, piezoelectric, thermoelectric, magneto-optic, magnetostrictive, or high-temperature materials;  advanced as well as traditional production technology and processing, additive manufacturing, 3D printing, Press and Sinter, HIP, MIM, PIM, Spark Plasma Sintering, Hot Pressing, Microwave Sintering, Plasma Treatment, Slip Casting, Rapid Heating, Ultrafast Sintering, new progressive compaction and processing methods;  influence of material processing parameters on their microstructure formation and development and structural relations of physical, mechanical, and functional properties of materials focusing but not limited on powder materials;  special technological processes of PM material with individual-particular-special physical-chemical properties;  environmental issues of production and application of PM materials;  industrial processes, management, and quality, (creation of normative) standard method activity, economical analysis, conception (philosophy) and prediction in PM and progressive material processing field;  production of technological equipment for powder and advanced materials technology.   The owner of the journal: Institute of Materials Research Slovak Academy of Science.  Why subscribe and read  PMP journal is an open-access journal that publishes original theoretical and experimental articles as well as review articles related to all aspects of PM. The journal is peer-reviewed, follows ethical publishing practices, and is searchable, discoverable, and citable.  Why submit  The journal has a distinguished Editorial Board with extensive academic qualifications, ensuring that the journal maintains high scientific standards and has broad international coverage. All manuscripts that are submitted to the PMP journal will NOT BE subject to any Article Processing Charges.  Rejection Rate   16.21 %   Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process. 