Densification of powder metallurgy billets by a roll consolidation technique

Container design is used to convert partially densified powder metallurgy compacts into fully densified slabs in one processing step. Technique improves product yield, lowers costs and yields great flexibility in process scale-up. Technique is applicable to all types of fabricable metallic materials that are produced from powder metallurgy process

Metallurgy and properties of plasma spray formed materials

Understanding the fundamental metallurgy of vacuum plasma spray formed materials is the key to enhancing and developing full material properties. Investigations have shown that the microstructure of plasma sprayed materials must evolve from a powder splat morphology to a recrystallized grain structure to assure high strength and ductility. A fully, or near fully, dense material that exhibits a powder splat morphology will perform as a brittle material compared to a recrystallized grain structure for the same amount of porosity. Metallurgy and material properties of nickel, iron, and copper base alloys will be presented and correlated to microstructure

Evaluation of Cyclic Behavior of Aircraft Turbine Disk Alloys

An evaluation of the cyclic behavior of three aircraft engine turbine disk materials was conducted to compare their relative crack initiation and crack propagation resistance. The disk alloys investigated were Inconel 718, hot isostatically pressed and forged powder metallurgy Rene '95, and as-hot-isostatically pressed Rene '95. The objective was to compare the hot isostatically pressed powder metallurgy alloy forms with conventionally processed superalloys as represented by Inconel 718. Cyclic behavior was evaluated at 650 C both under continuously cycling and a fifteen minute tensile hold time cycle to simulate engine conditions. Analysis of the test data were made to evaluate the strain range partitioning and energy exhaustion concepts for predicting hold time effects on low cycle fatigue

Hot tensile tests of Inconel 718

The physical metallurgy of near-solidus integranular cracking in Inconel 718 welds was investigated. The data, although inconclusive, suggest at least two mechanisms which might explain intergranular cracking (microfissuring) in the heat-affected zone of several high temperature alloys. One theory is based on the separation of intergranular liquid while the other involves mechanical failure of solid ligaments surrounded by intergranular liquid. Both mechanisms concentrate strain in the grain boundaries resulting in low strain (1%) intergranular brittleness. The mechanisms reported might also pertain to the physical metallurgy of casting, powder metallurgy sintering and hot isostatic pressing

Constant amplitude and post-overload fatigue crack growth behavior in PM aluminum alloy AA 8009

A recently developed, rapidly solidified, powder metallurgy, dispersion strengthened aluminum alloy, AA 8009, was fatigue tested at room temperature in lab air. Constant amplitude/constant delta kappa and single spike overload conditions were examined. High fatigue crack growth rates and low crack closure levels compared to typical ingot metallurgy aluminum alloys were observed. It was proposed that minimal crack roughness, crack path deflection, and limited slip reversibility, resulting from ultra-fine microstructure, were responsible for the relatively poor da/dN-delta kappa performance of AA 8009 as compared to that of typical IM aluminum alloys

The Corrosion Resistance of Iron-Tin Compacts as Produced by Powder Metallurgy

The art of Powder Metallurgy deals with the preparation of metal powders and their utilization. As a more pertinent definition, the following has been suggest­ed: Powder Metallurgy is the art of producing metal powders and shaped objects from individual, mixed, or alloyed metal powders, with or without the inclusion of non-metallic consti­tuents

The casting and powder-metallurgy forming of precipitation-hardenable stainless steels

Casting and powder metallurgy techniques for shaping precipitation hardened stainless steel

Production of Sponge Iron Powder by Reduction of a By-product of the Steelmaking Industry

Ref. Revista/libro: Proceedings of the International Powder Metallurgy Congress & Exhibition (PM2010). Volumen I. Editors: European Powder Metallurgy Association (EPMA). Florencia (Italia), October 2010.Rolling mill scale is a solid steelmaking by-product that contains metallic iron (Fe), wustite (FeO), hematite (α-Fe2O3) and magnetite (Fe3O4). It also contains traces of non-ferrous metals, alkaline compounds and oils from the rolling process. A study is made of the reduction of mill scale to sponge iron, in covered crucibles, using coke at different temperatures (1050º-1150ºC) and times (3-12 h). The final treatment of the samples was carried out in a hydrogen atmosphere furnace at 900ºC for 0.5 h. The reduced samples are studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Oxygen analysis is carried out by combustion in a LECO oven. The reduction of mill scale allows the new use and development of this material to obtain sponge iron that can be re-used to the electric furnace as metallic load in steel manufacturing or as a raw material in the production of iron-base powder metallurgy parts.European Powder Metallurgy Association (EPMA).Peer reviewe

FEATURES OF THE PROCESSES OF FORMING AND SINTERING OF POWDERED THERMOMAGNETIC MATERIALS ON THE IRON- NICKEL BASE WITH CHROMIUM ADDITIVES

Investigate the influence of chromium addition on the demagnetization temperature and Curie point of powder metallurgy thermomagnetic materials by determining the breakout force of its sample from a permanent magnet