Performance of powder-injection-molded W-4.9Ni-2.1Fe components

Microstructure and mechanical properties of titanium components fabricated by a new powder injection molding technique

“…However, while PIM has been used with great success in manufacturing a wide variety of metal products, including those made from stainless steel, nickel-based superalloys, and copper alloys [8][9][10], it has found far less application with reactive metals, such as titanium, primarily because of problems with interstitial impurities. In particular, high levels of oxygen are often found in inexpensive titanium powder sources.…”

A new binder for powder injection molding titanium and other reactive metals

“…(3) continue heating at 5 • C/min to 750 • C; (4) turn off the gas flow and begin pulling a vacuum on the heating chamber while holding at 750 • C for 3 h. • Under 10 −6 Torr vacuum: (5) continue heating at 20 • C/min to a final soak temperature of 1100 • C; (6) hold at 1100 • C for 4 h; (7) bleed in Ar and convectively cool to room temperature under flowing Ar. Under this heat treatment, the specimens sintered to an average density of 4.36 g/cm 3 (∼97% of theoretical for ␣-Ti).…”

“…As a result there has been increasing interest in developing lower cost methods of processing titanium alloys and one particularly attractive approach is powder injection molding (PIM). Derived from plastic injection molding and employing a mixture of metal powder and polymeric binder, PIM has been used with great success in manufacturing large volumes of small-to-moderate size, net-shape components out of metals such as steel, copper, and nickel [4,5]. However, the process has found far less application with reactive metals, such as titanium, zirconium, niobium, molybdenum, and tungsten, primarily because of problems with carbon and oxygen impurities.…”

Recent Progress in Processing of Tungsten Heavy Alloys

“…The tensile properties are comparable to the conventional press and sinter alloys of a similar composition [60]. The solvent debinding temperature and thermal debinding atmosphere are found to be the principal factors affecting the mechanical properties of the alloy [61,62]. Effect of agglomerates with different contents on the green and sintered properties of 97W-2.1Ni-0.9Fe heavy alloys for tensile specimens indicates that particle characteristics have no effect on the microstructure and mechanical properties because agglomeration remains as porous structure in the molded green compacts [63,64].…”

“…The microstructure and processing factors of the heavy alloys are the key to affect their mechanical properties. For WHAs, the main influencing factors of mechanical properties include compositions [27-33, 36-39, 83], processing type [71-73, 85, 95, 99, 103, 122, 132, 133] and temperature/time [41,43,62,76,86,97,104,105,134], tungsten grain size and shape effect [47,81,87,118], grain growth [46,82,110,112,117], interface bonding between W and matrix [80,90,114,130,131], and porosity and pore size distribution [49,83,118,124,125,127].…”