PowderMet          AMPM          Special Interest          TNT Presentations

038 - Development of a Master Alloy Powder for Cold Spray Repairs of 7xxx Series Alloys
Lorena Perez, University of Alabama

We are studying the effect of the chemical composition on the behavior of cold spray deposits to develop a performance-driven Al-Zn-Mg-Cu master alloy for solid state structural repairs of 7xxx series Al alloys. A series of Al-based powders with varying Zn, Mg, and Cu content were produced via gas atomization and processed by cold spray. For comparison, commercial AA7020 powder was also produced and cold sprayed. Copper content was found to significantly influence the mechanical properties. The cold spray material with high copper content demonstrated to have a lower elongation to failure (4%) and higher ultimate strength (440 MPa) than the low-copper alloy (8% elongation and UTS of 270 MPa). Additionally, the presence of non-essential and impurity elements also affected the mechanical performance. The AA7020 cold sprayed material, a low copper alloy, exhibited only 2 % elongation to failure, which is four times lower than the elongation of the custom alloy with similar Zn, Mg, and Cu content. The microhardness was not affected by the non-essential and impurity elements. However, the alloy with high copper content exhibited higher microhardness.

057 - Cold Spray Coating of AlCrCoFeNi High Entropy Alloy for Corrosion Protection of Powder Metal Parts
Ezeck Olinger, Penn State University, DuBois

Cold spray coating, also known as supersonic particle disposition, is a process that is applicable to corrosion resistance, dimensional restoration and wear resistance coatings. The unique ability to provide a corrosive resistant coating with convenience and environmental friendliness is the main attraction to cold spray coatings. In this study, a high entropy alloy with an equimolar composition of AlCoCrFeNi was cold sprayed on F-0008 powder metal part for surface modification and corrosion protection. The cold spray coating was performed at 600 °C in the air as well as in nitrogen atmosphere. To improve the surface coating, cold sprayed specimens were heat treated at 950 °C in argon atmosphere for 2 hrs. Corrosion testing was performed on as-sintered, cold-sprayed, and heat-treated specimens by exposing the specimens with salt-spray until corrosion state reaches ~ 50%, determined visually. Detailed characterization of the coating thickness, corrosion behavior, surface roughness, microhardness, and transverse rupture strength of the specimens are reported in this paper.

064 - Corrosion Behavior of AlCrCoFeNi High Entropy Alloy (HEA) Cladded on F-0008 by Spark Plasma Sintering (SPS)
Daudi Waryoba, Penn State University, DuBois

High-entropy alloys (HEAs) are presently of great research interest in materials science and engineering. HEAs typically contain at least five elements with equimolar or near equimolar concentrations. Because of their high-entropy effects, HEAs have the potential to be used in many applications such as high temperature materials, cryogenic materials, wear resistance, diffusion barriers, etc. They are traditionally fabricated by vacuum melting method. However, this method produces microstructure defects such as shrinkage cavity, porosity, and segregation. In this study, spark plasma sintering (SPS) was used for diffusion bonding(cladding) of AlCrCoFeNi onto iron core (F-0008) for surface modification and corrosion resistance. SPS was carried out at 50 MPa and 1150 ˚C for 5 min. Results on the microstructure, interface characterization, and corrosion behavior are presented.

047 - Material Development of MIM Inconel 713C for Aerospace Applications
Greg Goto, Parmatech Corporation

The aerospace sector, although having courted MIM for decades, still remains a relatively untapped market for the Metal Injection Molding industry. The part geometries of potential aerospace products and sometimes low production volumes, though not centered in the sweet spot for MIM, are still viable for the industry but there are several barriers to entry. Rigorous material validation/qualification requirements and the use of costly, less developed superalloy materials are two of the barriers one must navigate for the MIM parts supplier. Inconel 713C is a superalloy with high strength and corrosion resistance at elevated temperatures which is used for various aerospace applications. Material property optimization is critical to meet the requirements of the aerospace industry. This paper will detail the material development from powder selection to sinter process parameters for MIM Inconel 713C.

041 - An Update on MPIF Metal Injection Molding Standards
Michael Stucky, Norwood Medical

An Update on MPIF Metal Injection Molding Standards

095 - Evaluation of Water-Atomized Spherical Powder Modeling by MIM and AM
Junya Abe, Epson Atmix Corporation

Conventionally, water atomized powder has been used as a metal powder for MIM because of its cost advantage. However, since water-atomized powders are generally irregularly shaped, it is necessary to take measures such as using more binder to improve fluidity when applying them to MIM. The spherical powder produced by Epson Atmix Corporation's water atomization method is characterized by its higher sphericity and superior powder packing density compared to conventional water-atomized powders. Therefore, we evaluated whether the spherical powder could be used to obtain molding characteristics equivalent to or better than those of MIM products made with conventional water-atomized powder. We also evaluated the molding characteristics by applying the powder to AM.

The results showed that the use of this newly developed unique water-atomized spherical powder produced better molding characteristics than the use of conventional powder.

048 - Mechanical Property Assessment of PM-HIP Materials to Connect Modeling and Microstructure
Samuel Bell, Oak Ridge National Laboratory

Hot isostatic pressing (HIP) offers a promising route to reduce manufacturing costs by enabling near-net-shape production across a wide range of alloys and components. This capability is especially advantageous for traditionally challenging materials and applications, such as refractory metals and complex alloy systems that are difficult to machine using conventional methods. While powder metallurgy HIP (PM-HIP) has primarily been used for smaller specialty components, recent community efforts aim to expand its application across broader component sizes and industrial applications. ORNL is seeking to facilitate this effort by investigating the relationships among HIP processing parameters, can geometry, and material performance, including the integration of additive-manufactured cans to optimize these processes. A critical component of this research is the development of high-fidelity models to predict accurate shape and performance outcomes. This requires an understanding of the microstructure and material property evolution during the HIP process. To support model validation, experiments were performed with varying can geometries and interrupted at specific HIP cycle stages, enabling assessment of mechanical properties in correlation with geometry, microstructure, and density. Initial studies using 316L stainless steel provided a baseline, with work extending to other relevant steels and nickel-based alloys. Compression and tensile tests among other novel mechanical tests were performed on both fully and partially densified cans, offering key insights into material behavior during the HIP cycle.

007 - Latest Capabilities in Hot Isostatic Pressing for Advanced, Technical Ceramics
Andrew Cassese, Quintus Technologies

For the past half a century high-end metal and ceramic applications such as critical components in aerospace, nuclear, oil and gas, medical implants, and more have used hot isostatic pressing(HIP) to ensure quality while maximizing mechanical properties and reliability. Ceramic materials such as silicon nitride, high strength zirconia-alumina toughened systems, and polycrystalline transparent ceramics are all being advanced to take applications such as bearings for electrical machines , medical implants, and laser and LED host materials to a next level of performance.

Integration of state of the art in HIP is a key aspect for the develop and commercialization of these technical ceramics. The aim of this manuscript is to showcase the modern capabilities of HIP available to the manufacturing society; capabilities such as “Clean HIP” for a controlled process atmosphere, “Steered cooling” to deliver rates necessary to facilitate consistent cooling segments for increased HIP productivity and quality, and more.

059  - Influence of Vibrational Frequency and Time on the Packing Density of Powder in PM-HIP Canisters
Rodrigo Soltero, Amaero Advanced Materials & Manufacturing, Inc.

The ideal use of the PM HIP process is to produce near net shape geometries, thus reducing the amount of waste material and post-processing required. In order to do this in a cost effective and efficient manner, the input material and process need to be understood. This study examines the influence of vibrational frequency and filling process duration on the packing density of powder inside a canister. Trials using different combinations of process variables will be repeated and analyzed. The goal is to find parameters that yield reproducible results for a given alloy and/or particle size distribution. If one can replicate the packing density consistently, it allows them to control one of the variables that affects the densification of the compact. With better command over densification, the starting shape of the canister can be modified either by iteration or use of simulation tools, ultimately approaching the desired output geometry.

016 - Assessment of Recycled SUS 316L Powder on Microstructure and Mechanical Properties in Directed Energy Deposition
Soon-Jik Hong, Kongju National University

Directed Energy Deposition (DED) efficiently combines laser energy and metal powder to create a solid layer-by-layer structure, advantageous for industries like aerospace and automotive. Among DED-compatible materials, SUS316L stainless steel is notable for its mechanical strength and corrosion resistance. However, the effects of powder recycling on SUS316L properties remain underexplored, even as recycling offers material savings. This study examines the microstructure and mechanical properties of SUS316L samples produced via DED using both virgin and recycled powders. Recycled powders, sorted by distance from the laser source, were used to fabricate 30 x 30 x 20 mm³ samples. SEM, XRD, and EBSD analyses evaluated microstructural changes, while ONH and XPS assessed oxidation in recycled powders. Mechanical properties were tested via Vickers hardness and tensile strength. Results indicate that increased recycling leads to higher oxidation, causing incomplete melting and oxide inclusions in samples produced with recycled powder. Consequently, the yield strength in recycled-powder samples dropped by 55% compared to virgin-powder samples.

019 - The Impact of Tantalum Powder Re-Use on Build Properties During Laser Powder Bed Fusion
Matthew Osborne, Global Advanced Metals

Additive manufacturing of tantalum is shown to be a robust method for creating complex parts in applications including medical. AM has inherent advantages for efficient material usage over subtractive manufacturing due to producing near-net-shape components. Powder reuse increases the financial benefits of AM; however, degradation of the powder results in a finite number of reuses. More stable powder allows more reuses and lower costs.

During LPBF processing, powder size distribution (PSD) and chemistry can change due to spatter, condensate, and gas absorption. PSD influences powder flow characteristics, which is critical for powder spreading, while changes in chemistry can influence the strength of the solidified powder. Overall these changes in powder with reuse cycles can impact printed material density and mechanical properties. An understanding of changes in powder characteristics during reuse cycles is critical to maintaining the powder within specifications to prevent changes in part performance, and meet regulatory requirements.

This presentation will compare printed Ta and powder properties for consecutive LPBF builds by Croom Medical using a Colibrium M2 400W Series 5 printer with optimized parameters and Ta powder supplied by Global Advanced Metals. Tensile properties, density, dimensional consistency, and lattice structures will be analyzed for effects arising from the reuse of powder. It will be shown using high-quality starting Ta powder and optimized printing parameters, Ta powder may be reused multiple times for continued cost efficiency while maintaining part performance.

081 - An Investigation of Re-Used 6061 Aluminum Powder for Binder Jet Printing 
Nicholas Murphy, PMT, Kymera International

Feedstock use and reuse is an important topic for the development of Binder Jet additive manufacturing that has far reaching effects. Reuse of powder over time can affect powder properties, part properties, and ultimately the business case of binder jet AM. Here we will examine some of the changes that can be observed over time as 6061 Aluminum powder is continuously reused.

505 - Model-Based Decision Making in the Automotive Industry and Its Impact on the Powder Metallurgy Industry
Ian Donaldson, FAPMI, GKN Sinter Metals

There has been a rapid adoption in industry of model-based engineering, which is a formalized approach to engineering that uses models as a fundamental part of the conceptualization, analysis, implementation, and validation associated with complex systems. In the automotive industry, technical baselines have been established to facilitate understanding of the product performance and aid decision making through scenario planning. The objectives are to reduce costs, reduce time and detect early defects. A significant part of this is the use of material databases to reduce physical testing needs. The requirements for the databases are to have extensive accurate static and dynamic mechanical property data. This negatively impacts the powder metal (PM) industries because there is less data available than wrought or cast materials. This paper discusses the potential reduced opportunities for PM sourcing, steps needed to mitigate exclusion with examples of property requirements and use of modeling for decision making.

506 - Fatigue Performance of a FLC2-4208 Low Alloy Sinter-Hardened Steel
Ian Donaldson, FAPMI, GKN Sinter Metals

Automotive customers are quickly moving to model-based decision making in the design phase which is reducing the testing of components. The formalized application of modeling is done to support system requirements, design, analysis, verification and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases. The drivers are cost, early detection of defects or design issues and timing (reduced design cycle time). This requires significant mechanical property data of materials. While static properties of PM materials exist, fatigue data is much more limited which may exclude PM as a potential choice at the design stage. This is motivation to develop comprehensive fatigue properties at different densities and R ratios. In addition, the specific strength (e.g., σUTS/ρ or σFatigue/ρ) of the material provides an opportunity for PM since the density can be adjusted coupled with a wide flexibility in materials. Further discussion is provided on the supporting factor method from the FKM-Guideline which details where to construct synthetic stress-life curves (pseudo stress-life curves) of notched components.

508 - Plane Bending Fatigue Testing of Ferrous PM Materials
W. Brian James, FAPMI, PMtech

The typical fatigue endurance limit data in MPIF Standard 35–SP, Materials Standards for PM Structural Parts, were determined using stress-controlled rotating beam fatigue (RBF) testing under fully reversed stress conditions (R = -1). The test specimens used for this test method are machined in accordance with MPIF Standard Test Method 56 and are stress relieved and polished prior to testing to mitigate the presence of residual stresses that might affect the measured fatigue properties. The RBF test is limited to a single mean stress condition (R = -1) and does not enable the effect of mean stress to be determined. Plane bend fatigue testing, using test specimens specified in ISO 3928 can be performed at various mean stress levels. The test specimens can be produced directly by pressing and sintering eliminating the machining cost and the potential for residual stresses after machining. Specimens can be compacted to include a notch so the notch-sensitivity of the fatigue response may be evaluated. The Center for Powder Metallurgy Technology (CPMT) and the MPIF Standards Committee have jointly initiated a program to determine the plane bending fatigue performance of selected PM materials. The data will be included in the Engineering Information section of MPIF Standard 35–SP. Initially, testing will be conducted under stress control in fully reversed bending to determine the fatigue endurance limit of selected materials using the staircase method. The program will be expanded later to include tests at various mean stress levels, again with a focus on determining the endurance limit, with the aim of creating Haig diagrams to reflect the effect of mean stress on the fatigue performance of the materials. Initial tests on both a hybrid, sinter-hardenable alloy

FLC2-4208, and a prealloyed material FL-5008 will be reported.