Hoeganaes Corporation to Present at Powdermet 2016/AMPM Conference

6/2/2016 1:00 AM

Hoeganaes Corp. will give 7 presentations during the 2016 International Conference on Powder Metallurgy and Particulate Materials and concurrent AMPM conference. The conference runs June 5-8, 2016 at the Sheraton Boston in Boston, MA.


The Effect of Physical Properties of Lubricants on the Performance of Premixes

Alex B. Wartenberg, Hoeganaes Corporation

The objective of this study is to document how the physical characteristics of lubricants added to powder premixes affect the final properties of both the premix and the compacted and sintered parts. Parameters, such as lubricant size, shape, melting point and lubricity will be studied in relation to; both mix properties, such as apparent density and flow, as well as compacted part properties such as green and sintered density. Various forces exhibited during compaction and ejection will also be studied versus the physical properties of the lubricant. A means to optimize lubricant systems for die fill will be reviewed. Finally, the effect of the lubricant characteristics on mechanical properties such as tensile strength and fatigue life will be examined.

Improving the Sintered Dimensional Response of FC-0205 for Applications Requiring Restrictive Dimensional Control after Sintering

Fran Hanejko, Hoeganaes Corporation

Iron-copper-carbon powder metallurgy steels are the most widely used materials in the PM industry because simplified processing, good mechanical properties and low cost.  For example, these steels are the material of choice for automotive transmission carriers, main bearing caps, forged connecting rods and VVT components.  The VVT product family represents a part category that necessitates high sintered dimensional control often exceeding the inherent control capability of the FC-0205 type steel; often requiring extensive secondary machining to meet the product specification.  Key variables that were investigated were density distribution within the part, sintering temperature, production rate, lot to lot variations in the apparent density and sintered dimensional control of the supplied premix.  An optimization study was performed that investigated each of these variables to minimize the impact on the final sintered part.  This investigation optimized processing beginning with the powder premix thru part production enabling reduced scrap with improved productivity.

Improving Machinability of PM Components: Response of Novel Machining Additive and Predictability Analysis of Machining Behavior

Cecilia Borgonovo, Hoeganaes Corporation

The advantage of PM processing is the achievement of near-net-shape components with minimal material waste – under 5% -. Despite its close to die tolerances, secondary machining remains a necessary step for several PM applications, such as automotive – which constitute over 70% of PM business-  and aerospace. The need for high throughput and tight tolerances translate into developing a machining additive able to provide long tool life, constant dimensions throughout the machining process and reliability. MnS has shown to cause poor dimensional consistency and accelerated rusting, due to its chemical reactivity with moisture. A novel machining additive has been developed and an extensive analysis pursued. Tool life has been assessed for several machining conditions, dimensional and surface tolerances investigated, and an in-depth analysis of machining behavior carried out. Analytical considerations to determine predictability of machining behavior (time to tool failure) and of optimal machining conditions have also been addressed.


Metallographic Testing of Titanium Powders for Use in Additive Manufacturing

Thomas F. Murphy, Hoeganaes Corporation

An integral part of producing titanium powders for use in additive manufacturing (AM) is providing test data demonstrating the quality, uniformity, and consistency of the products.  Typically, chemical, mechanical, physical, and metallographic tests are performed to ensure the powders meet or exceed the expectations and requirements of specific applications.  Each test discipline provides unique information on the particle properties and expected behavior of the powder as the AM parts are produced.  The contributions of metallographic testing on quantifying the attributes of the powders are discussed in this paper.  The physical characteristics of particle shape and size distribution, along with the surface textures are examined.  In addition, the microstructural constituents of internal porosity, non-metallic inclusion content, microstructure, and alloy distribution are evaluated and discussed.  Light and electron microscopy, with automated image analysis techniques are used in these analyses.

Economic Additive Manufacturing Using Water-Atomized Stainless Steel Powder

Alex Zwiren, Hoeganaes Corporation

316L stainless steels are highly corrosion resistant steels utilized in applications ranging from handling chemicals in the process industry, pharmaceuticals, medical implants, to automotive applications. This stainless steel is characterized by good formability, weldability, and exceptional toughness. Primary alloying elements, chromium, nickel, and molybdenum provide exceptional resistance to corrosion. Due to these desirable qualities, 316L is an attractive alloy for Additive Manufacturing (AM). Essential powder characteristics (e.g. flowability, morphology) for AM are still being developed and understood. Gas atomization (GA) is the principle production route for powder aimed towards AM. Water atomization (WA) is another means to produce powder, albeit, with morphological and chemical characteristics slightly different to GA powder. This paper presents the morphological, microstructural, and mechanical properties of WA compared to GA 316L after being processed via Selective Laser Melting. The manufacturing process chain is developed to produce small series of complex parts and prototypes for automotive applications.

Special Interest Programs

Lean Alloy Opportunities in PM Structural Steels

Bruce Lindsley, Hoeganaes Corporation

PM steel alloys containing Mo, Ni and Cu have been successfully utilized in the industry for multiple applications.  Ongoing cost pressures in the automotive industry force a constant re-assessment of alloy selection and the need for leaner alloys.  Two approaches have been taken to address these concerns.  The first is to reduce the current alloying elements to the lowest level that will still meet required properties.  Powder grades with lower molybdenum content (0.3 and 0.5% Mo) have been introduced to provide increased flexibility in alloy selection.  Admixed nickel content optimized at levels less than 1% have also been found to provide sufficient toughness in the hardened condition.  The second approach is to evaluate alternative alloying elements that are more abundant and lower cost.  Chromium, manganese and silicon are widely used in the wrought industry and impart both an increase in strength and an improvement in hardenability.  Historically, these alloying elements have not been used extensively in PM steels as they reduce compressibility when prealloyed in the base iron and are easily oxidized.  Alternative alloying methods provide methods to employ these elements, leading to attractive mechanical properties in leaner alloy materials.  This presentation will explore the benefits and challenges of both approaches to lean alloy systems.

Development of a Microalloyed Bainitic Steel for PM

Chris Schade, Tom Murphy - Hoeganaes Corporation
Alan Lawley, Roger Doherty, Mitra Taheri, George Bernhard, Madeline Bouchard and Colleen Hyde - Drexel University                                                                          
Typical microstructures of PM steels are pearlitic (predominately occurring in the as sintered condition) or martensitic (occurring as the result of accelerated cooling or heat treatment). By design of the alloy system, a predominately bainitic microstructure can be produced in a PM steel after sintering. In the wrought ferrous industry, bainitic steels are known to exhibit high strength and hardness and also a high level of toughness. In order to achieve maximum strength and toughness it is necessary to form high percentages of lower bainite in the microstructure.  A number of alloying elements such as niobium, titanium and boron that are typically used in wrought steels for micro-alloying, also promote the formation of lower bainite. The goal of this study is to examine the effect of these alloying elements on both the formation of lower bainite and precipitation strengthening through micro-alloying in a PM alloy. Both microstructural analysis and mechanical properties of the various alloys will be compared.